Biology 232 Anatomy and Physiology II Sylvania Laboratory Survival ...

Biology 232 Anatomy and Physiology II

Sylvania Laboratory Survival Guide Anatomy and Physiology II Biology 232 Sylvania Laboratory Survival Guide

Biology 232, Anatomy and Physiology II, Sylvania Laboratory Survival Guide

Table of Contents

Lab Topic (Exercise in Marieb Manual):

page:

Safety Guidelines Disposal Guidelines

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Spinal Cord Objectives (Exercise 21) and Reflexes (Exercise 22) Cranial Nerve Introduction Brain Study Guide (Exercise 19) General Sensation (Exercise 23) Special Senses: Vision and Hearing (Ex. 24 & 25) Endocrine System (Exercise 27) and Glucometer Exercise Blood Lab (Exercise 29A) Cardiac Anatomy (Exercise 30) and Pre-EKG Lab EKG Lab (Exercise 31) Circulation (Exercise 32) and Blood Pressure and Pulse (Exercise 33A)

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When specimens in laboratory such as human bones (or other body parts), they may seem like inanimate objects that are far removed from a living organism. However, we ask that you continually remain cognizant of the fact that they were once parts of humans (or other living creatures). Please handle these body parts with respect and care.


PCC-Sylvania

Bi 232 Laboratory Supplement

1. Upon entering the laboratory, please locate the exits, fire extinguisher, eyewash

station, and clean up materials for chemical spills. The location of fire blanket, safety kit, and showers will be demonstrated by your instructor. 2. Read the general laboratory directions and any objectives before coming to lab. 3. Food and drink, including water, is prohibited in laboratory. This is per Federal laboratory guidelines and per College Safety Policy. Do not chew gum, use tobacco products of any kind, store food or apply cosmetics in the laboratory. No drink containers of any kind may be on the benches. 4. Please keep all personal materials off the working area. Store backpacks and purses at the rear of the laboratory, not beside or under benches. Some laboratory spaces have shelving in rear for this purpose. 5. For your safety, please restrain long hair, loose fitting clothing and dangling jewelry. Hair ties are available, ask your instructor. Hats and bare midriffs are not acceptable in the laboratory. Shoes, not sandals, must be worn at all times in laboratory. You may wear a laboratory apron or lab coat if you desire, but it is not required. 6. We do not wish to invade your privacy, but for your safety if you are pregnant, taking immunosuppressive drugs or who have any other medical conditions (e.g. diabetes, immunological defect) that might necessitate special precautions in the laboratory must inform the instructor immediately. If you know you have an allergy to latex or chemicals, please inform instructor. 7. Decontaminate work surfaces at the beginning of every lab period using Amphyl solution. Decontaminate bench following any practical quiz, when given, and after labs involving the dissection of preserved material. 8. Use safety goggles in all experiments in which solutions or chemicals are heated or when instructed to do so. Never leave heat sources unattended: hot plates or Bunsen burners. 9. Wear disposable gloves when handling blood and other body fluids or when touching items or surfaces soiled with blood or other body fluids such as saliva and urine. (NOTE: cover open cuts or scrapes with a sterile bandage before donning gloves.) Wash hands immediately after removing gloves. 10. Keep all liquids away from the edge of the lab bench to avoid spills. Immediately notify your instructor of any spills. Keep test tubes in racks provided, except when necessary to transfer to water baths or hot plate. You will be advised of the proper clean-up procedures for any spill. 11. Report all chemical or liquid spills and all accidents, such as cuts or burns, no matter how minor, to the instructor immediately. 12. Use mechanical pipetting devices only. Mouth pipetting is prohibited.

Students who do not comply with these safety guidelines will be excluded from the Laboratory

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232, Anatomy and Physiology II, Sylvania Laboratory Survival Guide

PCC-Sylvania

Disposal of contaminated materials

1. Place disposable materials such as gloves, mouth pieces, swabs, toothpicks and paper

2. 3. 4. 5.

6. 7.

8.

9.

10. 11.

12.

13.

toweling that have come into contact with blood or other body fluids into a disposable Autoclave bag for decontamination by autoclaving. This bucket is not for general trash. Place glassware contaminated with blood and other body fluids directly into a labeled bucket of 10% Bleach solution. ONLY glass or plastic-ware is to be placed in this bucket, no trash. Sharp’s container is for used lancets only. It is bright red. When using disposable lancets do not replace their covers. Properly label glassware and slides, using china markers provided. Wear disposable gloves when handling blood and other body fluids or when touching items or surfaces soiled with blood or other body fluids such as saliva and urine. (NOTE: cover open cuts or scrapes with a sterile bandage before donning gloves.) Wash hands immediately after removing gloves. Wear disposable gloves when handling or dissecting specimens fixed with formaldehyde or stored in Carosafe/Wardsafe. Wear disposable gloves when handling chemicals denoted as hazardous or carcinogenic by your instructor. Read labels on dropper bottles provided for an experiment, they will indicate the need for gloves or goggles, etc. Upon request, detailed written information is available on every chemical used (MSDS). Ask your instructor. No pen or pencil is to be used at any time on any model or bone. The bones are fragile, hard to replace and used by hundreds of students every year. To protect them and keep them in the best condition, please use pipe cleaners and probes provided instead of a writing instrument. Probes may be used on models as well. The bones are very difficult and costly to replace, as are the models and may take a long time to replace. At the end of an experiment: • clean glassware and place where designated. Remove china marker labels at this time. • return solutions & chemicals to designated area. Do not put solutions or chemicals in cupboards! You cannot work alone or unsupervised in the laboratory. Microscopes should be cleaned before returning to numbered cabinet. Be sure objectives are clean, use lens paper. Place objectives into storage position, and return to the storage cabinet. Be sure cord has been coiled and restrained. Your instructor may require microscope be checked before you put it away. Be sure it is in assigned cupboard. Please replace your prepared slides into the box from which they came (slides and boxes are numbered), so students using them after you will be able to find the same slide. Clean slide with Kimwipes if dirty or covered with oil, before placing back in box. If you break a slide, please, inform you instructor so the slide can be replaced. Please be aware that there are hundreds of dollars worth of slides in each box and handle the boxes with care when carrying to and from your work bench. Be sure all paper towels used in cleaning lab benches and washing hands are disposed of in trash container provided.

Students who do not comply with these safety guidelines and directions will be excluded from the Laboratory


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Spinal Cord (Exercise 21) 1. Study the Longitudinal View of the Spinal cord from a picture. a. Note how the spinal cord extends through the vertebral canal down to vertebral level L1 or L2. What is the tapered tip of the cord called? _____________________________ (Hint: It starts with a “C.”) b. How many pairs of spinal nerves exit the cord? ________________________ c. Why is a lumbar spinal tap made between vertebrae L3 and L4, not around L1? ________________________________________________________________ d. What is the name given to the grouped spinal nerves that extend down the vertebral canal below the lower tip of the cord? ______________________________ (Hint: Its name means “horse’s tail.”) e. What are the three meninges that cover the cord? Name these from outermost to innermost. inner meninge: middle meninge: outer meninge: _______________ _______________ _______________ f. Note the epidural space is outside the dura mater. A catheter (a thin hollow tube) can be inserted here to deliver a small amount of anesthetic, resulting in an “epidural” block. Leakage of a small amount of cerebrospinal fluid sometimes leads to a severe headache, called a spinal headache. Which procedure so you think carries a bigger risk of a spinal headache, a spinal block (which penetrates the dura and arachnoid); or an epidural block? __________________________

2. Study the cross section of the spinal cord from a model and histology slide. Use the dissecting microscope before using the compound microscope. a. Note the 3 meninges. Cerebrospinal fluid is in between the _________________ mater and the _________________ mater. b. In the spinal cord, is the gray matter inside or outside the white matter?_________________ c. View the cross section of the spinal cord (still using the dissection microscope.) What insect (or letter of the alphabet) does the gray matter look like? ________ d. Which contains cell bodies, dendrites, and unmyelinated axons, gray or white matter? ____________ e. Which contains mostly myelinated axons, gray or white matter? __________ f. White matter details: Note the narrow poster median sulcus; it may be hard to see on histology slides. Note the anterior median fissure; it is wider and is more easily observed on histology slides. What is the name for the canal in the center of the gray matter of the spinal cord? ____________________ It is lined with ependymal cells, which help circulate the cerebrospinal fluid (CSF.) g. The grey matter forms two posterior horns and two anterior horns. Which are longer? _________________ Which are thicker, but shorter? ________________ h. The white matter is divided into 3 columns, or “funiculi.” What are their names? _____________________ ____________________ _____________________

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3. Spinal Nerves and Nerve Plexuses. a. How many pairs of cervical spinal nerves leave the spinal cord? ______ b. Thoracic spinal nerves?______ pairs. c. Lumbar spinal nerves?______ pairs. There are also five pairs of sacral spinal nerves and one tiny pair of coccygeals. d. Draw a symmetrical sketch of the structures exiting the cord and label the following structures: 1. doral root 2. ventral root 3. dorsal root ganglion 4. spinal nerve 5. dorsal ramus. 6. ventral ramus

e. The dorsal root is carries sensory information; the ventral root carries motor information. Can we say the same about the dorsal and ventral rami? ________ f. Is a “spinal nerve” best described as sensory, motor, or mixed (sensory and motor)? _______________________ g. Which is farther away from the spinal cord, a nerve plexus or a peripheral nerve?________________________ h. Does a plexus contain any synapses (connections between neurons)? ________ i. Does a plexus contain neuron cell bodies? ________ j. Where could you find the cell bodies of motor neurons? __________________ k. Where could you find the cell bodies of sensory neurons? _________________ l. The cervical plexus arises from the ventral rami C1 though ______; and supplies the shoulder and neck. m. A major peripheral nerve that leaves the cervical plexus is the ________________ nerve, which innervates the diaphragm. It contains fibers of the ventral rami of C3, C_____, and _______. n. The brachial plexus contains fibers of the ventral rami of C5 through __________. It leads to nerves such as the median, ulnar, and radial nerves. o. Which peripheral nerve of the brachial plexus transmits sensation from the lateral two thirds of the palmar surface of the hand to the cord? ______________________ p. The lumbar plexus contains fibers of ventral rami L1 through _____. A large branch of the lumbar plexus is the femoral nerve. q. The sacral plexus contains fibers from which ventral rami? _________________. r. Which two peripheral nerves is the sciatic nerve continuous with? ______________________ and _____________________.


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4. Autonomic System

notes:

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Reflexes (Exercise 22) 1. Define a reflex. ________________________________________________________________________ ______________________________________________________________________ 2. What is an autonomic reflex? ________________________________________________________________________ ______________________________________________________________________ a. Give an example.__________________________________________________ 3. Somatic reflexes involve stimulation of ___________________________________by the somatic division of the nervous system.

4. In the above space, sketch the components of a reflex arc. Label the following: a. Receptor: examples include pain receptors in skin, and dendrities in the muscle spindles that monitor muscle stretch. b. Sensory neuron: note the position of the cell bodies of these unipolar neurons in the dorsal root ganglion (DRG.) c. Reflex center (integration center): Is this located in the CNS or PNS? ______ d. Motor neuron: note locations of the neuron cell body and axon e. Effector 5. How is the “modality” of a stimulus related to a receptor’s sensitivity? (i.e., Can you give an example of how a receptor’s structure explains its sensitivity to a particular kind of stimulus?)

6. What is a spinal reflex?___________________________________________________ 7. Stretch reflexes, also called “deep tendon reflexes,” are monosynaptic. What is their overall function? In other words, how do they benefit us? Using the correct names for the receptor and effector, sketch the reflex arc below.


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8. Practice the following deep tendon reflexes (“stretch reflexes.”) a. ankle jerk (tests spinal nerves S1, S2) b. knee jerk (patellar reflex, tests spinal nerves L2, L3, L4) c. biceps jerk (tests spinal nerves C5, C6) 9. Note that the spinal cord level is different from the vertebral level. The cord ends at vertebrae L1 or L2. In the distal cord there are neurons whose axons travel in spinal nerves which will exit the CNS at vertebrae L2-4. (Recall: What is the name of the bundle of nerves that leave the tip of the spinal cord and appear somewhat like a horse’s tail? ____________________________) 10. Grading of reflexes: 0+=absent, 1+=hyporeflexic, 2+=normal, 3+=hyperreflexia, 4+=clonus Read “zero plus,” “one plus,” “two plus,” etc. Conditions such as hypothyroidism and spinal shock diminish reflexes. Stimulant drugs, anxiety, and hyperthyroidism increase reflexes. 11. A patient remains relaxed during an accurate reflex test. If muscles are tense, then tapping the tendon will not stretch the muscle. Ask your patient to clasp his or her hands together while simultaneously looking up at the ceiling (or just close the eyes.) The aim is to avoid watching the examiner’s reflex hammer, while focusing all of one’s muscle tension on the upper extremities. This technique is called the “Jendrasic maneuver” and should relax the legs. 12. Look for symmetry while performing reflexes. For example, if someone has a herniated disc and a pinched spinal nerve, one ankle jerk may be weaker than the other. 13. Upper motor neurons typically inhibit the strength of the knee jerks. Loss of this steady inhibition is referred to as “disinhibition” and is analogous to removing your foot from the break of a car while traveling down a hill. What do you think would happen to the magnitude of the knee jerk reflex if someone suffers from a transected (cut) spinal cord well above L2-4? Would the reflex be increased or decreased? __________ Would the reflex be graded 1+ or 4+? _______________. 14. superficial cord reflexes (cutaneous reflexes) a. These reflexes depend on a normal upper motor neuron pathway and a normal cord-level reflex arc. Damaging the arc of the receptor/cord/effector will certainly diminish the reflex. Damaging the upper motor neuron may magnify the reflex by reducing the normal inhibition of the reflex (“disinhibition.”) b. Test the plantar reflex. This test is performed by ________________________________________________________________, Normally, the toes curl (plantar flex). If the upper motor neurons are damaged, then stroking of the foot as you described above will produce a ___________________________sign. In this sign, the toes flare and the big toe moves ___________ (up / down.)

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c. The Babinski sign is normally present in infants under 2 years old; it disappears as the nervous system develops (i.e., as the upper motor neurons develop and begin their inhibition.) d. Review: What is the difference between upper and lower motor neurons? (Where are the cell bodies of the lower motor neurons? Where are the bodies of the upper motor neurons?) __________________________________________________________________ e. Are upper motor neurons sensory or motor neurons? ________________ f. Are lower motor neurons sensory or motor neurons? ________________ 15. Cranial nerve reflexes a. Preview the cranial nerves. You will need to know them by name, number, and function. b. The afferent portion of the corneal reflex tests cranial nerve?________________. c. The gag reflex tests cranial nerve IX and CN ______________. 16. Autonomic reflexes a. The afferent portion of the pupillary reflex involves cranial nerve _________. b. The efferent portion of the pupillary reflex involves cranial nerve _________.


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Cranial Nerves (I-XII): The caudal CNs have higher numbers than the cephalad CNs. CN I, olfactory nerve Identify the olfactory bulb, (which is large in sheep brains, and which contains a collection of very short neurons that innervate the olfactory epithelium inside the nose. How do you test the function of CNI?_________________________ CNII, optic nerve Identify the optic chiasm (near the pituitary) where some fibers cross. Identify the optic tracts. Is the optic nerve sensory, motor, or mixed?______________ . How do you test the function of CNII?_________________________ CN III, occulomotor Identify this nerve to the extraocular muscles. This nerve also carries parasympathetic fibers innervating the iris; it mediates pupilary constriction. How do you test the function of CNIII?___________________________ CN IV, trochlear This is motor neuron exits from the dorsal surface of the brainstem and innervates one extraocular muscle. CNIV is tested by checking eye movements. CN V, trigeminal This mixed CN contains sensation from the face and cornea; it also sends motor fibers to muscles for chewing. How do you test for facial sensation?_________________________________. How do you test for sensation of the cornea?____________________________________. CN VI, abducens This CN carries motor fibers to one extraocular eye muscles. It is tested in common with cranial nerve III, occulomotor. CN VII, facial This CN caries motor fibers to muscles of facial expression, parasympathetic fibers to the lacrimal glands, and __________________________________glands. It also carries taste sensation from the anterior tongue. CNVII can be tested by asking a patient to close the eyes, smile, and whistle. Tearing can be tested using ammonia vapors. CN VIII, vestibulocochlear This CN caries sensory information from the vestibular system (for balance,) and the cochlea (for _______________________.) Hearing can be tested with a tuning fork. CN IX, glossopharyngeal This CN contains motor fibers to the pharynx, parasympathetic fibers to the salivary glands, sensory fibers from the posterior tongue and pharynx. The gag reflex is a test of the sensory and motor fibers. Taste sensation (from the posterior tongue) can also be tested. CN X, vagus

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This mixed CN contains sensory and motor fibers of the pharynx & larynx. The gag reflex is an appropriate test. Additionally, you should listen for hoarseness. The vagus nerve also sends _______________________(parasympathetic or sympathetic?) fibers to the heart and other viscera. CN XI, accessory This CN sends motor fibers to the trapezius and sternocleidomastoid muscles. What is the shoulder shrug test?__________________________________________________ CN XII, hypoglossal This CN sends motor fibers to the tongue. Test by asking the patient to stick the tongue out; note symmetry or asymmetry.


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Brain Study Guide (Exercise 19) For lab you need to identify and understand the basic function(s) of each of the listed structures. You will need to learn the functions from your lecture notes and lecture text, as the lab manual does not emphasize function. Learn the anatomy of the brain from several views. Use sheep brains, rubber brain, and models to study external view. See human brain for dura, arachnoid, & pia. Perform a sagittal dissection of a sheep brain. Study models and rubberized sagittal sections of the human brain. Study models and preserved human coronal & horizontal brain sections. Using these resources, identify the following structures: 1. Meninges: While looking at these meninges, note that the cerebral arteries are located on the surface of the pia, deep to the arachnoid. Two classic symptoms of meningitis are headache and stiff neck. a. Identify the dura, arachnoid, and pia mater Which is the toughest, outermost meninge? ______________________ b. Identify spaces between layers. Find the arachnoid villi. Cerebrospinal fluid is in between the _____________and ____________ mater. 2. Brainstem: a. Medulla. The decussation of the pyramids is where the major motor tracts cross. Other functions:______________________________ b. Pons. Functions _______________________________ c. Midbrain. Functions _______________________________ i. Corpora quadrigemina: on dorsal side of midbrain ii. Superior colliculi Function _______________________________ iii. Inferior colliculi Function ________________________________ d. Cerebral peduncles (on ventral side of midbrain.) In the cerebral peduncles, are the tracts motor or sensory? _________________ 3. Diencephalon: a. Thalamus. Functions _______________________________ b. Hypothalamus. Functions ________________________________ c. pituitary & mamillary bodies. Functions ___________________________ 4. Cerebrum: Examine external & sagittal views of the right and left cerebral hemispheres: a. Lobes: b. frontal Functions ________________________________ c. parietal Functions _______________________________ d. occipital Functions _______________________________ e. temporal lobes Functions _______________________________

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5. Review the functions of the lobes. a. Which lobe helps you initiate motor impulses?___________________________ b. Which lobe is the site helps you figure out what you have just touched?________. c. Which lobe contains your visual cortex? ________________________ You will suffer from a condition called cortical blindness if you have a stroke of this area, even though there is nothing wrong with your eyes. d. Which lobe is responsible for understanding the lyrics of a song that you that you might listen to?_______________________ 6. Major sulci & fissures a. Longitudinal fissure b. Lateral fissures (= “Sylvian fissure” = “lateral sulcus”) c. Central sulcus 7. Major gyri: a. pre-central gyrus and and post-central gyrus: b. Which gyrus is the primary motor area?_____________________________ . c. Which gyrus is the primary somatosensory area?_________________________ 8. White matter: a. corpus callosum; note septum pellucidum. b. Function of corpus callosum________________________________________ 9. Basal ganglia: Identify these clusters of internal grey matter (most grey matter is on the cerebral cortex, which is the surface of the brain) from illustrations in your book. The basal ganglia control accessory, semiautomatic movements such as arm swinging while walking, smiling when something is humorous, etc. They also help adjust muscle tone. a. Caudate nucleus b. Putamen c. Globus pallidus 10. Cerebellum a. vermis b. arbor vitae c. Functions ______________________________________________________ 11. Ventricular System a. Lateral ventricles (there are no first and second ventricles, just the two laterals) b. 3rd ventricle c. 4th ventricle d. Cerebral aqueduct=aqueduct of Sylvius e. Choroid plexus: can see inside ventricles of human brain in plastic 12. Cranial Nerves Learn the cranial nerves by number, name, and function. Study the anatomy of each nerve using your lecture and laboratory text. notes:


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General Sensation (Exercise 23) 1. Define Exteroceptor: 2. Define Interoceptor: 3. Define proprioceptor: 4. Observe a Pacinian corpuscle on a miscroscope slide of fetal palm. What modality of sensation does the Pacinian corpuscle detect? _________________________ 5. What does “punctate distribution” indicate when used to describe receptors? _____________________________________________________________________ _____________________________________________________________________ _________________________________________________________________ 6. Are hot, cold, and light touch receptors all at the same location? _____. Be able to describe how you proved this. 7. What is the two-point threshold on the fingertips? __________. 8. What is the two-point threshold on the back of the neck? __________. 9. Define two-point threshold and explain why there is a difference in thresholds on the fingertips and the neck. _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ 10. Perform the experiment that tests adaptation of temperature receptors. Explain your findings. _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ 11. What is referred pain? Use the pain that occurs in a herniated disc and the pain felt during angina pectoris to clarify your definition. _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ notes:

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Special Senses: Vision and Hearing (Ex. 24 & 25) 1. Use a model, diagram, and/or sheep's eye. Identify and describe the function of: a. cornea, iris, pupil, lens, sclera, b. choroid (contains tapetum lucidum in the sheep’s eye), optic disc, fovea centralis c. optic nerve, retina d. anterior segment (subdivided into the anterior & posterior chambers), aqueous humor e. posterior segment, vitreous humor 2. Review questions a. Which muscles of the iris constrict to decrease the size of the pupil? b. Name 2 examples of causes of pupillary constriction: c. Which muscles constrict to increase the size of the pupil? 3. Understand and be able to explain the following visual tests: a. Demonstration of blind spot: be able to predict what this means about the location of the optic disc compared to the fovea. (Hint: What is the relationship of the optic discs to the “blind spots” in your visual fields? Sketch a diagram of the eye, carefully noting the location of central and peripheral visual fields.)

b. Afterimages: if you didn’t do this in lab, you can do on own. Differentiate between positive and negative afterimage. c. Refraction: Define refraction. Diagnose hyperopia, myopia, or emmetropia from a diagram such as Figure 24.9, page 273 in your laboratory text. d. Astigmatism: Recognize the astigmatism testing chart. Differentiate astigmatism (abnormal curvature of the lens or cornea) from hyperopia & myopia. e. Visual acuity: Know the meaning of the upper value and the lower value in: 20/15, 20/20, and 20/40. 4. Eye reflexes: if you didn’t get them done in lab, you can still get them done at home. a. Photopupillary reflex: the pupil gets smaller when brighter light strikes the retina b. Accommodation: the pupil gets smaller when viewed objects are closer


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c. Convergence reflex:

Hearing and Equilibrium (Exercise 25) 5. Use a model or drawing. Identify and describe the function of the following: a. auricle, lobule, external auditory canal b. tympanic membrane c. malleus, incus, stapes d. cochlea, semicircular canals, vestibule e. cochlear portion of cranial nerve VIII f. vestibular portion of cranial nerve VIII g. auditory tube Know which structures are in the outer ear, middle ear, and inner ear. Which ossicle strikes the oval window?_______________________________________________ 6. Differentiate between sensorineural & conductive hearing loss. ________________________________________________________________________ ________________________________________________________________________

7. Perform the experiment that clarifies the role of vision in maintaining equilibrium. 8. Describe and perform the Weber and Rinne tests. Weber is elicited by ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ Rinne is elicited by_________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 9. If a Weber test sounds louder in the left ear, what are the two possible causes?

a. If the Rinne is negative on the left ear, and positive in the right ear, and the above Weber results are true, what is the diagnosis? ______________________________________ b. If the Rinne is positive in the left ear negative in the right (sounds softer in the right ear either with the tuning fork on the right mastoid, or when held up to the right ear) what is the diagnosis?______________________________________ note:

Intructors and Students: Plan ahead for next week! Volunteers needed: Volunteers will need to fast for the endocrine lab. (See below.)

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Endocrine System (Exercise 27, and Glucometer Exercise-see below) 1. Pituitary gland (the hypophysis): recognize this gland. a. Distinguish anterior from posterior. b. The anterior pituitary is more cellular than the posterior pituitary and is sometimes called the “adenohypophysis” (adeno=gland). c. The posterior pituitary (sometimes called the “neurohypophysis”) is rich in axons that descended from the ____________________ of the diencephalon. 2. Learn the anterior pituitary hormones. Complete this table; some blanks have been filled in for you. Mnemonic Device: Hugo Pulled an A in The Friday Lab. Hormone Abbreviation hGH

Hormone Name: Spell it out!

PRL

Major Effect(s) of each hormone

Stimulates Lactation

ACTH TSH

Thyroid Stimulating Hormone

FSH LH (MSH)

3. Learn the two posterior pituitary hormones. Complete this table. Hormone Hormone Name: Abbreviation Spell it out! OT ADH

Role in humans unclear

Major Effect(s) of each hormone

Causes kidneys to retain water, decreasing urine output

4. Identify the thyroid gland by recognizing its follicles. Make a sketch with the following structures labeled: a. thyroid follicles b. follicular epithelial cell, which form a simple cuboidal epithelium) c. colloid, which contains thyroglobulin, a protein that includes precursors to thyroid hormone. d. parafollicular cells, also called C cells, which secrete calcitonin, and are located between follicles (i.e., in the same regions as the blood vessels)


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5. Does thyroxine (thyroid hormone) stimulate or inhibit your metabolic rate? ___________ 6. Is thyroid hormone important for nervous system function and development?__________ Note: one action of calcitonin is to lower serum calcium levels in animals by driving calcium from the bloodstream into bone. Calcitonin’s effects on calcium may not be physiologically significant in humans, however. The level of calcitonin seen in human serum has a minimal effect in regulating the serum calcium. However, in medicine, very large injections of salmon-derived calcitonin are used to treat hypercalcemia. Injecting calcitonin to achieve higher than normal levels of this hormone in a patient’s blood is called pharmacologic dosing (as opposed to a physiologic dosing.) 7. Parathyroid glands: a. identify parathyroid tissue on the thyroid slide The dense clusters of dark blue chief cells (not “C cells” !) secrete PTH (parathyroid hormone.) 8. Complete the following table by writing up-arrows and down-arrows. PTH Effects on:

Write an up-arrow or a down-arrow to indicate an increase or decrease in the process in the left-hand column.

Rate of vitamin D activation (and thus calcium and phosphate absorption from the intestines into the blood.) Rate of bone dissolution by osteoclasts (and thus release of calcium and phosphate into the blood) Rate of calcium reabsorption from the kidney’s filtrate (and thus diffusion back into the blood) Net effect of PTH on serum calcium Rate of phosphate excretion into the urine Net effect of PTH on serum phosphate

9. Pancreas: identify pancreatic tissue a. acinar cells: exocrine function b. Islets of Langerhans: have endocrine function (secretes hormones into bloodstream). c. Although you can’t distinguish between alpha and beta cells, know that alpha cells secrete ______________________________(which raises your blood sugar) and beta cells secrete ____________________________(which lowers blood sugar)

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10. Adrenal gland: identify these layers of adrenal tissue a. capsule b. cortex c. medulla 11. Complete the following table regarding the 3 layers of the adrenal cortex: Layer of Cortex

Class of hormone secreted

Zona Glomerulosa

Mineralocorticoids example: aldosterone

Zona Fasciculata

Glucocorticoids examples: cortisol(hydrocortisone), corticosterone, and cortisone

Zona Reticularis

Sex Steroids examples: adrenal androgens, including dehydroepiandrosterone (DHEA)

Two effects of this class hormone Sodium and water retention, but potassium excretion (by kidney.) Thus, blood pressure rises and serum potassium drops.

Growth spurt and pubic hair formation and in puberty. Minimal role in postpubescent males (See testes.). In postmenopausal females, adrenal androgens are precursors to estrogens. Remember GFRMGS…i’ve Gone For a Ride in My Granny’s Subaru

12. List the hormones secreted by the adrenal medulla: a. _________________ and _________________ b. Which one of these is also released by sympathetic neurons?_________________ c. What do these hormones do to the heart rate? _____________________________ d. How do they affects cutaneous (skin) blood flow?__________________________ e. How do they affect skeletal muscle blood flow?___________________________

Note: Your instructor may wish to include the ovaries and testes here; they will be examined in detail during BI233.


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Glucometer Exercise: Note: this portion of the lab requires knowledge of universal blood precautions. (Read them now and review them again before you perform the blood lab.)

Objective #1: Learn the OR-OSHA Blood-borne Pathogens Standard 1. Blood-borne Pathogens include: HIV, Hepatitis B & C Viruses, etc. 2. Universal Precautions a. Fluids: all human blood and other body fluids such as semen, vaginal secretions, CSF, saliva, & any fluid contaminated with blood should be considered sources of blood-borne pathogens. b. Approach: treat all of the above fluids as if they contain blood-borne pathogens 3. Protective Equipment a. When to Use: When known occupational exposure will occur, employer (or school) needs to provide b. Disposable, single-use gloves. Hypoallergenic, powderless or liners required to be supplied for those with allergies to powdered gloves. c. Masks, Eye Protection, and Face shields: wear when splashes, spray, etc. may be generated & risk of eye, nose, or mouth contamination anticipated. d. First Aid Pocket Masks: used with CPR 4. Housekeeping a. Contaminated work surfaces: decontaminate with appropriate disinfectant: 1/4 cup household bleach per 1/2 gallon water b. Contaminated laundry: bagged, transported with labels color coded in compliance with OSHA standards. 5. All lancets should be disposed of in the “sharps” containers. All other materials that have contacted blood should be autoclaved.

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Background on Diabetes: The preferred way to diagnose diabetes mellitus is by measuring a fasting blood glucose level. A fasting value over 140 mg/dl on at two separate occasions indicates that a person has diabetes. Another way to diagnose diabetes is with a blood sugar over 200 mg/dl at 2 hours and on at least one other occasion during a two-hour oral glucose tolerance test (OGGT). If the two hour value is between 140 and 200 but the other value is over 200, then a diagnosis of “impaired glucose tolerance” is given. These individuals are at increased risk of developing diabetes. 1. A “normal” person will have an increase in blood sugar, but it should come back down fairly quickly due to the release of _______________________. A person with diabetes will have a higher blood sugar that stays elevated for long period of time. 2. The two major types of diabetes are a. Type I Diabetes, also called ______________________ Diabetes, and b. Type II Diabetes, also called ______________________Diabetes.

Objective #2: Oral Glucose Tolerance Test: The person that will be tested must not have any food or drink (except water) for at least TEN hours (no more than 16 hours) prior to the test. The person is in a “fasting state.” An initial blood sugar is drawn. Next, the person is given a bottle of 75 grams of glucose (about 300 Calories.) Blood samples can be drawn at 30 minutes, 1 hour, 2 hour after the drink. A typical cola contains 160 to 180 Calories per 12oz can in the form of fructose. Our experiment will be more limited. Two volunteers should have fasted, and two volunteers should not have fasted. Your lab group may use a different number of students, and may take measurements at slightly different time intervals. Measure the below: Student 1 Student 2 Student 3 Student 4 Fasting Blood Glucose Blood Glucose ___ minutes after drinking cola. Blood Glucose ___ minutes after drinking cola. Blood Glucose ___ minutes after drinking cola. Blood Glucose ___ minutes after drinking cola. 3. What type of carbohydrate is in cola? ___________________________________ 4. How is this sugar converted to blood glucose?______________________________ 5. Exactly how many grams of carbohydrate are present?__________grams. 6. Exactly how many Calories does this represent?_________ Calories. What is your interpretation of the results that you saw in the two students? Discuss the results, thinking of the roles of insulin and glucagon in your answers. Biology 232, Anatomy and Physiology II, Sylvania Laboratory Survival Guide

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Answer the following questions: 7. Why weren’t the two “fasting” students’ blood sugars lower? What hormone(s) helped prevent hypoglycemia (blood sugar under 60) during their fast? ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ 8. If the blood sugar level rose immediately after the sugar was ingested, but then dropped, which hormone was responsible for the drop? _____________________________ 9. On your own, sketch the two negative feedback loops that regulate serum blood sugar. When the level of sugar is too high in the serum, where is the excess stored? When the level of sugar is too low in the serum, where is extra sugar found? 10. Review: If you have time, your instructor may wish to review the effects of growth hormone, cortisol, and glucagon on serum glucose levels.

notes:

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Blood Lab (Exercise 29A) Be certain to read through all of the objectives before beginning this laboratory session. Objective #1: Review the OR-OSHA Blood-borne Pathogens Standard 1. Blood-borne Pathogens include: HIV, Hepatitis B & C Viruses, etc. 2. Universal Precautions a. Fluids: all human blood and other body fluids such as semen, vaginal secretions, CSF, saliva, & any fluid contaminated with blood should be considered sources of blood-borne pathogens. b. Approach: treat all of the above fluids as if they contain blood-borne pathogens 3. Protective Equipment a. When to Use: When known occupational exposure will occur, employer (or school) needs to provide b. Disposable, single-use gloves. Hypoallergenic, powderless or liners required to be supplied for those with allergies to powdered gloves. c. Masks, Eye Protection, and Face shields: wear when splashes, spray, etc. may be generated & risk of eye, nose, or mouth contamination anticipated. d. First Aid Pocket Masks: used with CPR 4. Housekeeping a. Contaminated work surfaces: decontaminate with appropriate disinfectant: 1/4 cup household bleach per 1/2 gallon water b. Contaminated laundry: bagged, transported with labels color coded in compliance with OSHA standards. 5. All lancets should be disposed of in the “sharps” containers. All other materials that have contacted blood should be autoclaved.


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Objective #2: Practice Making a Blood Smear using Wright’s Stain 1. Materials: gloves, alcohol wipes, sterile lancet, cotton ball, 2 slides, paper towels, Wright’s stain, squirt bottles of distilled water and buffer.

Î Do not allow another student to come in contact with your blood; use gloves even while handling your slide after the staining procedure. 2. Place slide #1 on the table top. 3. Clean one finger (3rd or 4th finger on the hand you don’t write with works best) with alcohol and allow it to dry. 4. Using a new lancet, prick the tip of the finger. 5. Wipe away first drop of blood using the cotton ball. 6. Let second drop of blood fall (only about ½ inch) to land about ½ inch from the end of the slide. 7. Cover your fingertip with a Band-Aid and put gloves on both hands. 8. Hold the second slide at 45-degree angle to slide #1, and touch the center of slide #1. 9. Slide slide #2 slowly into the drop of blood, so that slide #2 barely touches the drop of blood. The drop of blood will spread out along edge of slide #2. 10. Using a steady, continuous motion in the opposite direction, pull slide #2 back across slide #1 to make a thin smear. Much of the blood will remain in its original place on slide #1, but a thin film should now extend toward the opposite end of slide #1. 11. Gently wave slide #1 in the air to dry. It will look dull when dry. 12. Place slide #1 on a paper towel, and cover whole smear with a few drops of Wright’s stain. (Count the # number of drops!) 13. Wait 3 minutes. 14. Drain the Wright’s off in the sink. Then add an equal # number of drops of buffer. 15. Wait 1 minute with the buffer still on the slide. 16. Now gently squirt the slide with stream of distilled water (over the sink) for about 1 minute. The slide should be flooded with distilled water. 17. Allow to lay flat for 30 seconds. 18. Stand slide on long edge on paper towel, allowing it to dry completely. 19. Dispose of blood-stained paper towel and gloves in labeled bag up front. 20. Disinfect the tabletop and make sure that you and your partner are gloved-up.

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Objective #3: Identify the different cells or cell fragments in a blood smear, learn their relative numbers, and learn their functions. 1. Examine the slide and identify the following: a. erythrocytes b. platelets c. three types of granulocytes d. two types of agranulocytes

Table of Formed Elements of the Blood Cell Type

Erythrocyte (RBC=red blood cell) iron deficient RBC sickle cell Reticulocyte

Nuclear Appearance

Cytoplasmic Function or cell Appearance Erythrocytes red; pale carries O2 lack nuclei center due and CO2 to biconcave disc more pale sickle shape to cell bluish-red

red cell precursor

Platelets


Count

hematocrit in women: 42% +/-5 in men: 47% +/-5

1-2% of red cells in a smear are reticulocytes 130,000-400,000 per cubic millimeter

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Leukocytes (White blood cells) includes granulocytes and agranulocytes Neutrophil 3-6 lobes (polymorphonuclear leukocyte, PMN, or “segs”)

4,300-10,800

intermediate colored granules

neutrophilic band (A “band cell” is relatively common precursor of the neutrophil described above.) Eosinophil

Horseshoe shaped nucleus

intermediate colored granules

bilobed

red granules

Basophil

U-S shaped blue with 2-3 granules constrictions

Monocyte

large, pale with dent or cleft

gray-blue; no granules; largest WBC

Lymphocyte

round, occupies most of cell

blue; cell about same size as red cell

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phagocytosis of bacteria & fungi, mediates acute inflammation marrow precursor of PMN

45-74% of total leukocytes

combats parasitic worms, phagocytizes immune complexes Histamine in granules: vasodilator, attracts other WBC’s leaves blood to become macrophage in tissue: phagocytic & presents antigens B cells: form plasma cells to make antibodies; T cells: destroy grafts, tumors, & virusinfected cells.

0-7%

0-4% is normal; % in smear increases with bacterial infection

0-2%

4-10%

16-45%



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Objective #4: Learn how to type your blood for ABO & Rh antigen systems; understand how the procedure is done, be able to draw a diagram of a transfusion reaction involving a recipient of blood which has not been adequately typed. 1. Definitions a. antigen (Ag): a substances that causes the immune system to produce antibodies and/or T cells that react with it. b. immunogenicity: the ability to stimulate antibody (Aby) formation c. reactivity: chemically binding to antibody (Aby) d. antibodies (Aby): complex proteins made by plasma cells in response to Ag; they are capable of combining with the Ag to form an Aby-Ag complex. e. Immunoglobulins (Ig): one of five groups (IgA, IgD, IgE, IgG, IgM) to which a particular antibody can belong. Some immunoglobulin types have similar functions; others differ in their function, location, and quantity in your body. 2. Structure: a. Antigen Structure: a protein with a lipid, carbohydrate, and/or nucleic acid attached. b. Antibody Structure: Y-shaped, with the two prongs of the Y capable of binding to a particular antigen. The structure of the prongs is highly variable; it depends on the specific antigen that the antibody is meant to bind to. An antibody does not change to adapt to new antigens, but new antibodies (with different Y’s) can be made when new antigens appear. The amount of a particular antibody can increase dramatically if you are exposed (or re-exposed) to the matching antigen. Note: An entire microorganism or its various components may be antigenic. Red cell antigens are cell surface molecules projecting out of the cell membrane. 3. Grouping (Typing) of Blood a. Membranes of RBC's contain a blood group’s antigen proteins. (These blood antigens are just a few of a person’s “self” antigens.) b. The plasma contains antibodies against non-self antigens that a person has been exposed to. (That is, a person’s immune system usually does not produce antibodies against a person’s own self antigens, and does not produce antibodies against foreign proteins if the protein has never contacted the immune system.) c. ABO: antigen proteins “A” and “B” determine a person’s blood type. A person’s RBCs may have the antigen proteins “A,” or “B,” or “A and B,” or neither. “Type O blood” indicates that the RBCs have neither antigen A nor antigen B. (There is no “O” antigen protein.) Blood serum contains antibodies (such as anti-A and/or anti-B) that bind to specific antigens (such as A and/or B)., but… 4. Antibody Rule: You don’t produce an antibody against any “self” antigen proteins that you have, or else you would attack your own red blood cells. 5. You will have antibodies against foreign antigens (the antigens that you do not possess.)

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6. Examples: a. Type O blood serum will contain both anti-A and anti-B antibodies. b. Type AB blood serum won't have anti-A or anti-B antibodies. c. Type A blood serum contains only anti-B antibodies, d. Type B blood group contains only anti-A antibodies. e. No blood contains anti-O antibodies because O is not an antigen! (Remember, “O” simply indicates the absence of A and B antigens.) 7. Genetics: Homologous alleles (a pair of inherited alleles) determine a person’s blood type. A person inherits two alleles (one from each parent); each of the two alleles may be A, B, or O, so a person may have the “genotype” of AA, BB, AB, AO, BO, or OO. An allele results in the presence of the corresponding protein, thus: a. genetic combination AB will lead to type AB blood i. A and B antigen proteins are present b. genetic combination OO will lead to type O blood i. Neither A nor B antigen proteins are present c. genetic combinations AA or AO will lead to type A blood i. A antigen proteins only are present d. genetic combinations BB or BO will lead to type B blood i. B antigen proteins only are present 8. Questions: a. What parental genetics are needed to yield a child with OO (Type O) blood? b. In the above situation, is there more than one possibility for each parent’s blood type? c. Could two parents have a child with Type O blood and a child with Type AB blood? d. Could two parents have a child with Type O blood and a child with Type A blood? 9. Technique: an unknown sample of blood is mixed with a known antiserum (containing anti-A, or anti-B, or anti-Rh antibodies.) Agglutination (clumping) indicates that the unknown blood contained an antigen that reacted with the specific antiserum. 10. Examples: a. anti-A antiserum agglutination: this shows that the blood contained the A antigen protein (i.e., the blood was A, or AB.) b. anti-B antiserum agglutination: this shows that the blood contained the B antigen protein (i.e., the blood was B, or AB.) c. anti-A and anti-B agglutination: this shows that the blood contained the A antigen and the B antigen protein (i.e., the blood was AB.) 11. Rh antigens a. Rh is a RBC antigen protein, similar to A and B. It is inherited (+),or not (-), independent of the ABO blood grouping. b. Individuals whose RBC's contain Rh antigens are called “positive,” while those without Rh antigens are called “negative.”


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c. “O negative” blood contain neither A, nor B, nor Rh antigen, while “AB positive” blood contains all three antigens. 12. Hemolytic disease of the newborn ( also called erythroblastosis fetalis) a. Rh+ father & Rh- mother conceive Rh+ fetus. During the delivery, the mother is sensitized due to exposure to the fetal Rh+ blood. She starts producing anti-Rh antibodies. b. If the mother becomes pregnant again, her anti-Rh antibodies will cross the placenta. If the fetus is again Rh+, then the fetal blood will be attacked by the anti-Rh antibody. This causes the destruction of RBCs (hemolysis.) c. Prevention: Injection of RhoGam to Rh- mothers right after delivery, miscarriage, or abortion will “block” the foreign (fetal) Rh antigen proteins, so the mother's immune system will not "see" it and won’t be sensitized. The mother then won't form anti-Rh antibodies. 13. Testing your own RBCs a. Materials: 2 slides, gloves, white paper background to lay slides on, lancet, alcohol, cotton, Band-Aid, anti-A antiserum, anti-B antiserum, and anti-Rh antiserum, three clean toothpicks b. Slide 1: write “anti-A” on the left edge and write “anti-B” on the right edge c. Slide 2: write “anti-Rh” d. Do not allow one antiserum to contact another. Place one drop of each antiserum on the slide next to its name on the appropriate slide. e. Clean off your finger with alcohol, and prick it with the lancet. Discard first drop of blood into cotton, then drop 1 drop of blood into each antiserum. f. Making sure to use different toothpicks for each antiserum, stir the blood and antiserum. Watch for the clumping of an agglutination reaction (the linking of RBCs together by the Y-shaped antibodies binding to the antigens on the RBCs.) Draw a diagram of the following interactions, including the donor red cells, their cell surface antigens, and the recipient’s antibodies. You do not need to draw the antibodies of the donor blood because these antibodies are usually removed prior to transfusion into the donor. 14. Type A person (recipient) inadvertently is given type B blood (donor)

15. Type O person given type AB blood

16. Type AB person given type O blood

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blood type

serum antibodies present

red cell antigens present

can receive blood from these types

can donate blood to these types

Review: 17. Which is the universal donor? a. Why? b. Is it O negative, or O positive? 18. Which is the universal recipient? Why? 19. Discuss hemolytic disease of the newborn and Rh incompatability.


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Objective 5: Using the HemoCue hemoglobin photometer, measure the hemoglobin concentrations on two males and two females in the class. 1. Record Results: Male 1 Male 2 Female 1 Female 2 2. 3. 4. 5.

Normal hemoglobin concentration in females is 12-16 g/deciliter. Normal hemoglobin concentration in males is 13-18 g/deciliter. Normal hematocrit in females is 37-48%. Normal hematocrit in men is 42-52%.

6. Hematocrit can be estimated from the hemoglobin concentration: 3x hemoglobin=hematocrit.

7. Why is there a gender difference? Testosterone is in high concentration in males; this stimulates synthesis of erythropoietin which in turn stimulates erythropoiesis (red cell formation) in the red marrow. Lower values in women of reproductive age may also reflect their red cell losses due to menstruation.

notes:

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Cardiac Anatomy (Exercise 30) Cardiac disease is the most common killer in the US. The cardiac portion of the Adam Interactive Physiology CD ROM that comes with your lab manual is GREAT!!! 1. Histology: look at the intercalated disc slide (cardiac muscle.) a. Cardiac cells have one nucleus/cell and visible striations . b. Cardiac cells are branched and they are connected by intercalated discs (which contain many gap junctions connecting the adjacent cell cytoplasm.) c. These cells are under involuntary control, unlike skeletal muscle, which is under voluntary control. 2. Position in the thorax and covering of the heart: a. Apex =tip It points inferiorly, anteriorly, and to the left. b. The pericardium, a serous membrane, surrounds the heart within the mediastinum. 3. Position of the heart related to intercostal spaces: a. During ventricular systole (contraction), the apex presses against the chest in the 5th intercostal space about 8 centimeters to the left of the midsternal line. This is called the PMI (Point of Maximum Impulse.) 4. Pericardium: a two-layered membrane a. The visceral pericardium, the inner layer, covers the outer surface of the myocardium; it is also called the epicardium. Note the presence of epicardial fat in the pig heart. b. The parietal pericardium, the outer layer, is fibrous and is separated from the visceral pericardium by the pericardial space 5. Layers of heart, from outer to inner: a. epicardium (=visceral pericardium) b. myocardium (muscle). Note where it is thickest. Is it the left ventricle, the right ventricle, or one of the atria?___________________________________ Why?______________________________________________________ c. endocardium (a simple squamous epithelium) 6. Chambers: a. The auricles (dog-ear like projections) help you to identify the anterior surface. b. right atrium (RA) c. right ventricle(RV). The moderator band (in the sheep heart) helps prevent overfilling. d. left atrium (LA) e. left ventricle (LV) 7. Outer Surfaces & landmarks a. apex (tip of LV) b. base (mainly LA)=posterior surface


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c. anterior interventricular sulcus (surface depression between LV & RV) d. diaphragmatic, or inferior surface (mostly LV & some RV) e. anterior surface: mainly RV & RA 8. Vessels entering or leaving chambers & degree of oxygenation of blood: a. superior vena cava, inferior vena cava, and coronary sinus drain deoxygenated blood into the right atrium. What is the coronary sinus?_____________________________________________ b. pulmonary trunk carries deoxygenated blood away from the right ventricle. It leads to the left and right pulmonary artery. c. pulmonary veins drain oxygenated blood (from the lungs) into the left atrium; these are often cut off so you may not see them when examining the pig heart. d. aorta carries oxygenated blood away from left ventricle. The ascending aorta leads to the aortic arch. e. Which vessels arise from the ascending aorta? __________________________________________________________ f. Which arteries arise from the aortic arch? __________________________________________________________ 9. Valves: a. Tricuspid: separates RA & RV; it is anchored to papillary muscles in RV by the chordae tendineae b. Pulmonic Semilunar: separates RV and the pulmonary trunk c. Mitral (use this term rather than bicuspid): separates LA & LV; it is anchored to papillary muscles in LV by the chordae tendineae d. Aortic: separates LV and the aorta e. Review of the order of the heart valves by tracing the route of blood as it first enters the right atrium. (Hint: TPMA = I Tried to Pull Many A’s) 10. Trabeculae: ridges and folds found only in the ventricles 11. Moderator band: a band of tissue between the septum and lateral wall of right ventricle seen in four-legged animals. It prevents overfilling of their heart (which might occur while they're running). In humans, it doesn't span the RV like does in sheep, & contains right bundle (of conduction system) in it.

Coronary arteries exit from ascending aorta just cephalad to aortic valve. They are imbedded in the superficial epicardial fat and send branches deep into the myocardium. Learn the clinical names given here, which are not the same ones written in your lab manual. 12. Left main coronary artery has two branches: a. Left Anterior Descending, “LAD,” runs in anterior interventricular sulcus. The text uses the name anterior interventricular branch. b. Circumflex , or “circ,” runs around the left side of the heart in the coronary sulcus between the left atrium (LA) and left ventricle (LV.)

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13. Right coronary artery, “RCA,” descends in the coronary sulcus between the right atrium (RA) and right ventricle(RV.) a. marginal branch: runs along RV toward apex b. on inferior surface: posterior descending artery “PDA”(note PDA is actually more on the inferior than the posterior surface); PDA may anastomose (=connect) with LAD. 14. The tip of the RCA may anastomose with the circ. Think of someone with coronary disease, such as narrowing of the left anterior descending (LAD.) Why would it be helpful to have anastomoses between coronary arteries? ________________________________________________________________________ ________________________________________________________________________ 15. Conduction system: Using a diagram from your lab manual, draw a sketch of the a. sinoatrial node b. atrioventricular node c. bundle of His d. right & left bundle e. Purkinje fibers.


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Pre-EKG Laboratory (You should do objectives 1-6 the week of the Cardiac Anatomy lab as a pre-lab before you perform EKG’s the following week.) Background reading: refer to your laboratory manual, and answer the following questions: 1. Define EKG 2. EKG Paper a. How many millivolts is each tiny vertical square in the standard EKG? b. How many seconds is one tiny horizontal square in the standard EKG? c. Note that every fifth line is slightly darker. What is the time interval between these slightly darker lines? Define a. P wave b. QRS complex c. T wave d. ST segment. Be able to circle this on a tracing. Note: when circling the ST segment, do NOT circle part of the QRS complex or the T wave! 3. Label the waves in a QRS complex. Note: QRS complexes are highly variable in appearance; these complexes do not always have all three waves (the Q,R, and S wave). DO NOT label a wave in the QRS complex if it’s not present!!!! • Q wave=negative deflection before an R wave. • R wave=positive deflection in QRS • S wave=negative deflection after an R Wave Learn this golden rule: when waves of depolarization are spreading through the heart, the inside of the cells turns positive. Positive waves of depolarization going towards positive electrodes create upward deflections on the EKG. Positive waves going away from positive electrodes (or towards negative electrodes) create negative deflections on the EKG. To decide if a QRS complex is positive, if the height of the R wave is more than the depth of the Q and S wave, then the overall QRS complex is considered to be upward, or positive. 4. Draw a QRS complex with a tiny Q wave, a tall R wave, and a tiny S wave. It’s considered an overall positive QRS. 5. Draw a QRS complex with a deep Q wave, and a tiny R wave. It’s considered a negative QRS.

6. Define a. QRS Axis b. P-R interval. P-R interval goes from the start of the P to the start of the QRS, even if the QRS begins with a Q wave. c. Q-T interval

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EKG LAB Record an EKG for one student, or more if time allows. Make copies for other students, one per row. On the tracing, Identify 1. P wave: what does it represent?______________________________________ 2. QRS complex: what does it represent?_________________________________ QRS AXIS: Knowing where the net wave of ventricular depolarization (QRS axis) is headed in space can give us information about the heart. The QRS axis tends to go somewhere between straight to the left (zero degrees) and straight down ( + 90 degrees). 3. What does it mean when the QRS is upright in lead I (which has the left arm positive and the right arm negative)? Circle one of the following sentences: a. The wave of depolarization is going towards the left. b. The wave of depolarization is going towards the right. c. The wave of depolarization is headed down towards the feet. d. The wave of depolarization is headed up towards the head. 4. What does it mean when the QRS is upright in lead II (which has the left leg positive and the right arm negative)? Circle one of the following sentences: a. The wave of depolarization is going towards the left. b. The wave of depolarization is going towards the right. c. The wave of depolarization is headed down towards the left foot. d. The wave of depolarization is headed up towards the head. 5. Combine the information from the above two sentences you circled and draw an arrow (=vector) to indicate the direction that the wave of depolarization of the ventricles is traveling in space. Do you notice any similarities between it and the orientation of the heart? If the QRS axis is down and to the left, then it is somewhere in between 0 and 90 degrees, which is normal. (The normal range for the QRS axis is from –30 degrees, a bit up and to the left to + 100 degrees, which is a bit down and to the right.) 6. What does the width of the QRS complex tell you about the speed of conduction through the ventricles? Remember, one tiny box on the EKG paper equals 0.04 seconds. The QRS should be no more than two and a half tiny boxes wide, or 0.10 seconds. It is often two tiny boxes wide, or 0.08 seconds. 7. T Wave: What does it represent? 8. P-R interval: What part of the conduction system is responsible for fairly long duration of the P-R interval?


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NOTE: The P-R interval is the time interval from the START of the P wave to the START of the QRS, regardless of the appearance of the QRS complex. The P-R interval should be between 0.12 and 0.2 seconds. A longer P-R interval may indicate a first degree atrioventricular block. It often means that there is disease of the AV node. Heart RATE (HR): Using standardized EKG graph paper, the distance between each line is 1mm, and represents 0.04 seconds. Every 5th line is drawn in heavy black; the interval between heavy black lines is 5mm, and thus represents 0.20seconds (1/5th of a second, or 1/300th of a minute.) Calculate heart rate: 1. Find an R wave on a heavy black line. If the next R wave lands on the next heavy black line to the right, then the HR is 300 beats / minute. If the next R wave lands on the 2nd black line, then the HR is 150 beats / minute. The subsequent black lines would show a heart rate of 100, 75, 60, and 50 beats / minute. 2. Or, just count the number of cycles/per 6 second strip. Multiply by 10 to calculate the number of beats in a minute (60 seconds.) Rhythm: 1. The heart rate is usually set by the sinoatrial node (SA node.) Other areas of cardiac tissue can act as a pacer when the SA node is damaged. a. The AV node paces at about 50 beats/minute. b. Ventricle tissue will pace at about 30 beats/minute. 2. Normal sinus rhythm(NSR): implies a HR of 60 to 100, with a QRS complex after every P wave, and a regular rhythm. 3. Sinus tachycardia: HR>100, normal rhythm 4. Sinus bradycardia: HR