Download BIO 202 EXAM 1 2025/2026 LATEST UPDATE FULL ACTUAL EXAM WITH COMPLETE SOLUTIONS and more Exams Biology in PDF only on Docsity!
BIO 202 EXAM 1 2025/2026 LATEST UPDATE FULL ACTUAL EXAM
WITH COMPLETE SOLUTIONS
What are the functions of an artery, arteriole, vein, venule, and capillary? Arteries : blood flows Away from heart Arteriole: small artery Veins: blood Visits the heart Venule: small vein Capillary: tiny vessels that connect veins and arteries From outermost to innermost, what are the three tunics (layers) of an artery. Tunica adventita Tunica intima Tunica media What layer of an artery consists mostly of smooth muscle? Tunica intima Why do larger veins have valves? in larger veins one-way valves allow blood to flow only toward heart
What is a venipuncture? the puncture of a vein as part of a medical procedure, typically to withdraw a blood sample or for an intravenous injection What is the name of the space in a blood vessel where blood flows? Lumen Explain the major differences between arteries and veins. Veins have different tunics/layers, not as much elasticity or smooth muscle - not nearly as much pressure or blood pressure regulation - it is a return due to gravity or muscle contraction around vein to get blood back to heart Veins have one way valves to prevent back flow of blood Describe the importance of the elasticity of an artery? What happens to this elasticity as one ages? How would this affect a person? maintains blood pressure even when heart relaxes Describe the pathophysiology of varicose veins. Blood pools and back flows because of broken valves Compare and contrast systemic and pulmonary circulation.
Epicardium (Visceral Pericardium) - inside layer of sac that covers the outer surface of the heart What is the name given to the thin, tough sac which covers the heart? What happens if blood gets caught in the space between between this sac and the heart itself? pericardial cavity/pericardium If blood gets in there, it causes Pericardial Tamponade - compression of the heart What is the muscular (middle) layer of the heart is called? Myocardium What type of tissue comprises the bulk of the myocardium? Cardiac muscle What is the inner lining of the heart called? Endocardium Where would you find the sulci of the heart? Coronary sulcus - divides atria and ventricles Anterior and posterior interventricular sulci: separate left and right ventricles contain blood vessels of cardiac muscle
Where would you find the interatrial setpum and interventricular septum of the heart? Interatrial septum - wall between atria Interventricular septum - thicker wall between ventricles Where will you find the bicuspid and tricuspid valves in the heart? These valves are sometimes referred to as AV valves? What does AV stand for? In between the atria and ventricles Called AV valves (atrialventricular) Bicuspid = Left AV valve Tricuspid = Right AV valve Where will you find the pulmonary and aortic semilunar valves in the heart? In the atria going to the aorta and the pulmonary trunk What chambers of the heart function to receive blood from the veins? Atria What are the bottom two chambers of the heart called? Ventricles
the left ventricle - it has to pump blood all the way around the body, but the right ventricle only has to pump it to the lungs Label all of the chambers of the heart. Trace the pathway of blood flow through the heart (don't forget to include circulation to and from the lungs). Picture What are the veins, in relation to the cardiovascular system, which carry oxygenated blood? How many are there? Veins - visit the heart Superior and inferior vena cava - carry deoxygenated blood to the heart (2) Pulmonary veins - carry oxygenated blood to the heart (4 - 2R 2L) What are the arteries, in relation to the cardiovascular system, which carry deoxygenated blood? How many are there? Arteries - Pulmonary arteries - carry deoxygenated blood to the lungs (1 trunk, 2 arteries) Aortic artery - carries oxygenated blood to the whole body (1) What is the largest artery of the human body?
The aorta Draw AND label the arrangement of blood vessels arising from the aortic arch. Make sure to include the fact that there is no left brachiocephalic trunk! ☺ The Aortic Arch serves the upper body by passing into the: Brachiocephalic Trunk (notice the right common carotid does not come directly off the aortic arch!) Left Common Carotid Artery Left Subclavian Artery Descending Aorta Discuss the role and the importance of the coronary arteries and coronary veins. The heart is a muscle and needs oxygen like the rest of our tissues, these bring oxygenated blood to the heart Compare and contrast angina and an infarction. How would the symptoms differ? Angina pectoris - partial obstruction of coronary blood flow can cause chest pain; pain caused by ischemia (restricted blood flow), often activity dependent Myocardial infarction - complete obstruction causes death of cardiac cells in affected area; pain or pressure in chest that often radiates down left arm
Draw AND label the four phases of an action potential of a plain old regular heart cell (cardiocyte). Then, answer the following questions: a. What is the resting potential value? b. What causes the threshold to be reached? c. What is the threshold value? d. When sodium gates close, which gates open? e. The influx of calcium into the heart cell causes what to happen. Hint: Think actin and myosin! ☺ f. What ion is responsible for repolarization? g. How does the length of the action potential compare to an action potential in a skeletal muscle cell? Why is this important? h. Summarize the role of calcium ions in cardiac muscle contractions. a. Resting potential: - 90mV b. Threshold met when stimulated by neighboring cardiocyte c. Threshold: ??? d. Na+ close, Ca2+ open e. SR releases more Ca2+ and causes actin and myosin to make a contraction f. Potassium causes repolarization g. much much slower AP than skeletal muscle, this is contraction and constant beating that needs to stay active, can't get tired out quickly h. Calcium causes the contraction to occur and for blood to flow Step 1 - Depolarization (very brief) Stimulus (from neighboring cardiocyte) opens voltage regulated Na+ gates, (Na+ rushes in) membrane depolarizes rapidly Action potential peaks at +30 mv Na+ gates close quickly
Step 2 Plateau - 200 to 250 msec (long), SUSTAINS CONTRACTION Slow Ca2+ channels open, Ca2+ binds to fast Ca2+ channels on SR, releases Ca2+ into cytosol: Contraction Step 3 Repolarization - Ca2+ channels close, K+ channels open, rapid K+ outflux returns cell to resting potential Draw AND label the four phases of an action potential of a pacemaker cell in the heart. Then, answer the following questions: a. What ions slowly leaks out of the cell, helping the cell to begin to depolarize? b. What is the funny current? c. What ion is primarily responsible for depolarization once threshold is reached? d. How does the pacemaker cell repolarize? e. What is the significance of the slow depolarization of the pacemaker cell? a. K+ slowly leaks out b. Funny current is K+ leaking out and Na+ leaking in, slowly depolarizing to threshold c. Depolarization caused by Ca+ opening d. Repolarize by Ca+ closing and K+ opening (flowing out) e. The K+ is slowly leaving, causing it to be slow List several ways that a ventricular heart cell and pacemaker heart cell differ in terms of action potential generation. Cardiocyte: no threshold, fast depolarization, long phase of contraction, fast repolarization Pacemaker cell: threshold of - 50 or - 40mV, Ca2+ opens (instead of Na+), slow repolarization, hyper-polarization then back to threshold, has funny current
f. Make sure to relate which regions of the ECK correlate to the regions of the heart that are depolarizing. a. P wave - atria depolarize b. P-R interval - from start of atrial depolarization to start of QRS complex c. QRS complex - ventricles depolarize d. Q-T interval - from ventricular depolarization to ventricular repolarization e. T wave - ventricles repolarize f. above What is an ectopic focus of pacemaker tissue? How can this be problematic? Ectopic foci - region of spontaneous firing (not SA) Latent pacemaker cells can control HR, it means the SA node isn't functioning correctly? It can be less accurate or productive What does the P-R interval allow to happen during the contraction of the heart? Allows AV node to slow it down so the ventricles have time to fill up and get ready to contract What happens if the P-R interval is too long? In other words, where is the wave of depolarization getting bottle necked? The ventricles may not receive the signal to depolarize, therefore getting rid of QRS and T waves - ventricles don't contract Getting cut off at P wave
What is atrial fibrillation? Why might someone have to be on blood thinners if they have this condition? AF - irregularly irregular - fast without any regularity - super fast - like a bad drummer Blood doesn't get through because of quivvering atria, there will be little blood clots and could cause strokes - people take blood thinners with it What is a PVC? Can this be a normal occurrence? PVC - premature ventricular contractions Get an early beat in ventricle that originates in the ventricle Feels like a big thud - if get 3 or more togetehr, it can be really bad It can be normal if it only happens once really rarely - can be caused by epi or norepi release What is V-Tac? What can this degenerate into? ventricular tachycardia - Vtach - QRS is too wide - bipassing specialized electrical cells Probably unconscious It can turn into V-Fib What is V-Fib? Why is this really, really bad? ventricular fibrulation they are for sure unconsious - quivvering - not enough O2 in body Vfib is really bad AKA cardiac arrest
Diagram the phases of the cardiac cycle making sure to include what is happening to the chambers of heart, the valves in the heart, and on an EKG during the following: a. Atrial systole b. Isovolumic contraction of the ventricles c. Ventricular ejection d. Isovolumic relaxation of the ventricles e. Late ventricular diastole (passive ventricular filling) f. Yes, you should probably draw out that huge cardiac cycle graph showing the EKG, Ventricular Pressures, and Left Ventricular Volume. You will probably see this on the MCAT and definitely on your medical licensing boards. You may ask, why draw it if it's already right there in front of you? Because by drawing it out and labeling it yourself, you will learn! ☺ Trust me! 1a - diastile - passive filling - filling based on pressure gradient between the atria and ventricles - lower pressure in ventricles and higher in atria 1b - atria are not contracting yet, the AV valves are open to fill the ventricles - ventricular diastole 1c - systole - aggressive the atria contract and get atrial kick (last 10% goes to Atraia and ventricles 2 - ventricles contract, same volume, but blood ain't movin' yet - same volume, ventricles contracting but the volume doesn't change, squeezing a full water bottle with the cap on AV Valves slammed shut (S1 heart sound - the lub of lub dub of heart) - makes pressure and prevents backflow 3 - ejection, blood is moving (steps 2 and 3 are both ventricular systole) - squeezing blood out 4 - ventricular diastole - isovolumetric relaxation - ventricles relax, pressure drops, volume stays the same, aotric and pulmonary valves shut S2 heart sound Valves make sounds when they shut lub dub lub dub lub dub - this is a cycle, it repeats over and over again
Explain the origin and the timing of the S1 and S2 heart sounds. S1 - First heart sound - louder and longer "lubb", occurs with closure of AV (tricuspid and bicuspid) valves - ventricles are contracting isovolumetric (contraction phase - pressure building but blood isnt moving yet) S2 - Second heart sound - softer and sharper "dupp" occurs with closure of semilunar valves (aortic and pulmonary valves) Predict the causes and timing of the cardiac murmurs discussed in class. Murmur is abnormal blood flow across valve - it is a sound; not a disease Blood going through narrow path, going backwards, stenosis = narrow Describe Cardiac Output (CO) and predict what factors can increase or decrease CO. Amount Of Blood Ejected By The Ventricle In 1 MINUTE Cardiac Output = Heart Rate X Stroke Volume About 4 To 6L/Min At Rest Vigorous Exercise CO To 21 L/Min For Fit Person And Up To 35 L/Min For World Class Athlete What exactly is a pulse? What are normal pulse ranges for men and women? What is tachycardia? Bradycardia? Can these either of these two conditions be "normal?" Explain! Surge of pressure in artery Infants have HR of 120 bpm or more Young adult females avg. 72 - 80 bpm
a. Autonomic nerve fibers involved. b. Neurotransmitters involved. c. Effects on the pacemaker cardiac action potential. d. Effects of extreme sympathetic stimulation or damage to the vegas nerve. e. Effect of atropine on the muscarinic Ach receptors of the heart's pacemaker tissue Cardioacceletory: Cluster of neurons in cardioacceletory center - when fires - motor out of grey matter, sympathetic chain, goes to SA and AV nodes (norepinephrine) Brain has small control over the heart and HR Epinephrine hits Beta 1 acceptor on heart causing it to speed up (on SA and AV node) Reduced repolarization - each beat, you are closer to threshold - don't need as much funny current to hit threshold Slope (m) of area under dotted line is more steep WHEN EPINEPH IS AROUND - allows SA node to depolarize more quickly Cardioinhibitory: Slows things down Vagus wanders everywhere - even to AV node and SA node Parasymp - releases Ach on receptors to slow things down Intrinsic rate - property of SA node without stimulation - goes about 100x a minute, due to parasymp firing, it keeps it close to 70 or 80 at resting, more relaxed = parasymp outflow and even lower If you get excited, sympathetic goes up and causes HR to go up and be stimulated more M2 is a muscarinc receptor Parasympathetic outflow to heart Second messenger system Ionotropy - strength of contraction
Chronotropy - HR If someone is in cardiac arrest - you want to stimulate sympathetic or block parasympathetic Atropine blocks parasympathetic, part of resusitation - with paddles Membrane potential goes further from threshold - hyperpolarizes Na+ Slows down funny current Predict the effects of the following chronotropic chemicals: a. Catecholamines b. Caffeine c. Nicotine d. Thyroid hormone Remember Chronotropy = Affects Heart Rate a. Catecholamines (NE And Epinephrine) (Neurotransmitters - Camp 2nd Messenger) Potent Cardiac Stimulants b. Caffeine Inhibits Camp Breakdown c. Nicotine Stimulates Catecholamine Secretion d. Hormones TH increases Adrenergic Receptors In Heart by changing how DNA in pacemaker cells is read, makes more B 1 adrenergic receptors, increases Sensitivity To Sympathetic Stimulation, increases HR
