BISC306 Test 2 Review

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Place the structures in order according to the path of blood circulation through the heart.

Systemic venous circulation 1. venae cavae 2. right atrium 3. right ventricle 4. pulmonary artery 5. lungs 6. pulmonary vein 7. left atrium 8. left ventricle 9. aorta Systemic arterial circulation

Which of the following statements regarding the cardiac cycle is correct?

The atrioventricular valves are open during mid-to-late diastole

When do the first and second heart sounds occur, in relation to an ECG?

The first heart sound occurs right after the R wave, and the second heart sound occurs right after the T wave

Which statement accurately describes the mechanism of the length-tension relationship? - The muscle generates the greatest amount of tension when it is stretched, because the thin filaments have the longest distance to travel. - The muscle generates the greatest amount of tension when it begins its contraction from resting length, because the thin filaments do not have very far to travel. - The muscle generates the greatest amount of tension when it begins its contraction from resting length, because the thin filaments can travel a great distance. - The muscle generates the greatest amount of tension when it is shortened, because the thin filaments do not have very far to travel

The muscle generates the greatest amount of tension when it begins its contraction from resting length, because the thin filaments can travel a great distance.

The circulatory system of mammals is arranged in two separate circuits, the pulmonary circuit, and the systemic circuit. In this double circulation system, blood is pumped through the heart twice. Identify the route of blood transport in the pulmonary circuit and the systemic circuit. - The pulmonary circuit transports blood to and from the body, and the systemic circuit transports blood to and from the lungs - The pulmonary circuit transports blood to and from the lungs, and the systemic circuit transports blood to and from the kidneys - The pulmonary circuit transports blood to and from the lungs, and the systemic circuit transports blood to and from the body - The pulmonary circuit transports blood to and from the brain, and the systemic circuit transports blood to and from the body

The pulmonary circuit transports blood to and from the lungs, and the systemic circuit transports blood to and from the body

Considering the structure and function of the human heart, why are the walls of the ventricles much thicker than the walls of the atria? - Ventricles are more susceptible to myocarditis, or inflammation of the myocardium, which leads to the thickening of the walls over time - Because the ventricles are larger chambers, they have more fat lining the walls to provide insulation and structural support. - The atria expel blood over a greater distance and therefore have a lesser pericardium layer for superior flexibility in contraction. - The ventricles expel blood over a greater distance and therefore have a larger myocardium layer for increased strength. - The ventricle walls contain more nervous tissue in the form of the sinoatrial node, which acts as the pacemaker of the heart

The ventricles expel blood over a greater distance and therefore have a larger myocardium layer for increased strength.

What is the function of heart valves? - Valves allow ions to pass between cardiomyocytes - Valves ensure that blood moves in one direction through the heart - Valves separate oxygenated blood from deoxygenated blood - Valves contain receptors that detect and maintain blood pressure

Valves ensure that blood moves in one direction through the heart

With regard to normal muscle physiology, what is complete tetanus? - maintenance of low-level muscle contractions - a continuous, fused contraction of the muscle - the result of fewer calcium ions in the sarcoplasm - a single, isolated muscle contraction

a continuous, fused contraction of the muscle

Which change is associated with an increase in vagal stimulation of the heart? - an increase in cardiac output - an increase in heart contractility - a decrease in heart rate - a decrease in parasympathetic tone

a decrease in heart rate

What is heart block? - a coronary artery blockage due to fatty deposits - a blood clot in the heart - a disrupted signal transmission in the heart - a series of rapid and irregular heart contractions

a disrupted signal transmission in the heart

Select the description of a neuromuscular junction. - a site where a motor neuron meets a muscle fiber - a site where muscle fibers meet to form a tendon - a site where one neuron transmits a signal to another neuron - a site a sensory neuron meets the epidermis of the skin

a site where a motor neuron meets a muscle fiber

What is a capacitance vessel? - a vessel that is highly elastic, which tolerates large changes in blood pressure - a vessel that is fenestrated, which allows the quick diffusion of nutrients out of blood - a vessel that is distensible, which accommodates a large percentage of blood volume - a vessel that is contractile, which propels and distributes blood to peripheral tissue

a vessel that is distensible, which accommodates a large percentage of blood volume

Extensibility

ability to lengthen and stretch

Elasticity

ability to regain shape after stretching or constricting

Excitability

ability to respond to a stimulus

Contractility

ability to shorten and generate force

Which enzyme is responsible for degrading the neurotransmitter that remains in the synaptic cleft after a muscle contraction? - glutamate decarboxylase - acetylcholinesterase - cysteine protease - alcohol dehydrogenase

acetylcholinesterase

What is bradycardia? - an abnormal stretching of the ventricles - a series of rapid, irregular heart contractions - an abnormally low heart rate - a heart rate above 100 beats per min

an abnormally low heart rate

What is hyperplasia? - a developmental abnormality involving changes in cell size, shape, and appearance - the reversible transformation of a differentiated cell type to another cell type - an increase in cell size within an organ or tissue - an increase in the number of normal cells within an organ or tissue

an increase in the number of normal cells within an organ or tissue

What is the Frank-Starling law of the heart? - a decrease in end diastolic volume results in an increase in stroke volume - an increase in heart rate results in an increase in stroke volume - an increase in ventricular filling results in an increase in stroke volume - end systolic volume minus end diastolic volume equals stroke volume

an increase in ventricular filling results in an increase in stroke volume

What causes the dicrotic notch in a graph of aortic pressure? - atria contracting - aortic valve closing - bicuspid valve closing - pulmonary valve closing

aortic valve closing

Ventricular contraction

begins just after the Q (of QRS)

Which of the following is greater? - blood pressure when parasympathetic stimulation to the heart increases - blood pressure when sympathetic stimulation to the heart increases

blood pressure when sympathetic stimulation to the heart increases

The plateau of the action potential in cardiac ventricular cells results from the opening of voltage-gated slow ______ channels in the plasma membrane of the cell.

calcium

In which region of the vasculature is blood flow velocity the slowest? - veins - superior vena cava - capillaries - pulmonary arteries - arterioles

capillaries

What is the term for a network of fine branching blood vessels that are found between arterioles and venules? - metarteriole - fenestrated capillaries - capillary bed - sinusoid

capillary bed

In an isotonic contraction, the muscle ________. - changes in length and moves the "load" - rapidly resynthesizes creatine phosphate and ATP - does not change in length but increases tension - the muscle does not tire as easily

changes in length and moves the "load"

What is atrophy? - programmed cell death - increased cell number - decreased cell size - increased cell size

decreased cell size

As blood moves from the arterial end to the venous end of a capillary, net filtration pressure:

decreases, as blood hydrostatic pressure decreases

Which microscopic structure is found in smooth muscle cells but not in skeletal muscle cells? - Z disc - dense body - sarcomere - myosin filament

dense body

When blood is centrifuged and its components separate, the bottom of the tube holds the:

erythrocytes

What is edema? - inflammation of tissues due to an infection - fluid loss from tissues due to dehydration - excess fluid buildup in a tissue compartment - excess cell growth in a tissue compartment

excess fluid buildup in a tissue compartment

The thin filament is an ATPase - true - false

false

Which of the following changes would most increase the resistance to blood flow in a blood vessel?

halving the diameter of the vessel

Which of the blood components is responsible for carrying the majority of oxygen found in blood? - prothrombin - hemoglobin - neutrophils - platelets

hemoglobin

Curare is an inhibitor of acetylcholine receptors at the motor end plate. This would result in - inability of the muscle fiber to respond to nervous stimulation - more acetylcholinesterase production - sustained contraction of the muscle - increased stimulation of the muscle - lack of calcium uptake by the muscle fiber

inability of the muscle fiber to respond to nervous stimulation

Which of the following is not a usual result of resistance exercise? - increase in the number of muscle cells - increase in the efficiency of the respiratory system - increase in the number of myofibrils within the muscle cells - increase in the efficiency of the circulatory system

increase in the number of muscle cells

If the pressure gradient in a blood vessel is increased while resistance remains unchanged, how is blood flow affected? - decreased - no change - cannot determine - increased

increased

Define cardiac arrhythmia - irregular contraction pattern of the heart - heart beating in sinus rhythm - abnormally slow heart rate - normal impulse conduction in the heart

irregular contraction pattern of the heart

The force per unit area that blood places on the inside wall of a blood vessel

is called the blood pressure

Events of excitation contraction coupling, such as the release of calcium from intracellular stores, occur during the _______ period of a muscle twitch. - latent - relaxation - contraction

latent

Choose the best definition of plasma. - endocrine hormones carried by the blood - liquid matrix of blood - blood proteins that aid in clotting - cells that carry oxygen-binding hemoglobin

liquid matrix of blood

Skeletal muscles are almost never completely relaxed. Even when a skeletal muscle is not fully contracting or moving, the nervous system automatically stimulates different groups of motor units, which creates a small degree of contraction. What is the name of this mechanism? - muscle tension - muscle tone - isometric contraction - concentric contraction

muscle tone

Which layer of the heart is responsible for making the heart beat? - pericardium - endocardium - epicardium - myocardium

myocardium

Muscle contraction is caused by - filaments lengthening of the sarcomere - actin filaments pulling on myosin filaments - the shortening of each myosin filament - myosin heads pulling actin filaments closer

myosin heads pulling actin filaments closer

Normally, the hydrostatic pressure difference between capillary fluid and interstitial fluid favors movement of fluid ________ the capillary. The osmotic pressure difference between capillary fluid and interstitial fluid favors movement of fluid ______ the capillary.

out of, into

Which of the structures regulates the flow of blood through capillary beds? - intercellular clefts - precapillary sphincters - arteriovenous anastomoses - varicose veins

precapillary sphincters

Capillary reabsorption is the movement of fluid from the interstitial space into the capillary lumen (into the blood plasma). What is the driving force for this inward movement? - pressure exerted by proteins suspended in interstitial fluid - force exerted by interstitial fluid on the outside of capillaries - force exerted by blood plasma on the capillary walls - pressure exerted by proteins suspended in blood plasma

pressure exerted by proteins suspended in blood plasma

The aortic valve

prevents the backflow of blood into the left ventricle during ventricular diastole

What is fibrillation? - faster-than-normal heart rate - premature contraction of the ventricles - rapid, uncoordinated contractions of cardiac muscle - blood regurgitation through the atrioventricular valve

rapid, uncoordinated contractions of cardiac muscle

How does visceral smooth muscle ultimately respond to stretch? - generating tension concentrically - relaxing - contracting - resisting the stretch

relaxing

Which fibers dominate many of the back and calf muscles that contract almost continually to maintain posture? - fast, glycolytic fibers - fast, oxidative fibers - slow, oxidative fibers - slow, glycolytic fibers

slow, oxidative fibers

Match a functional description to each component of thin filaments found in cardiac and skeletal muscle. - Actin - Tropomyosin - Troponin

- Actin: a structural protein that binds the thick filament during the cross-bridge cycle - Tropomyosin: a regulatory protein that blocks the thick filament binding sites - Troponin: a regulatory protein that binds calcium, causing a conformational change

Match each definition to the appropriate term. - Blood flow - Blood pressure - Resistance

- Blood flow: the volume of blood that passes through the body in a set amount of time - Blood pressure: the force blood exerts on blood vessel walls - Resistance: the force that opposes blood flow

Classify the given muscle properties as pertaining to cardiac, skeletal, or smooth muscle.

- Cardiac muscle: has striations and a moderately regular structure, is autorhythmic, is found in the heart - Skeletal muscle: has striations and a highly regular structure, must be stimulated by nerves, attaches bones to one another - Smooth muscle: has no striations, can be autorhythmic or activated by nerves, is found in the digestive tract

Which are characteristics of type O blood? (select all that apply) - Has anti-A antibodies - Has surface antigen B on its erythrocytes - Has anti-B antibodies - Has surface antigen A on its erythrocytes - Has surface antigen O on its erythrocytes

- Has anti-A antibodies - Has anti-B antibodies - Has surface antigen O on its erythrocytes

Match the descriptions with the appropriate kind of skeletal muscle contraction. - Isotonic - Isometric - Concentric - Eccentric

- Isotonic: peak muscle tension does not equal load, muscle length changes - Isometric: peak muscle tension never exceeds load, muscle length remains constant - Concentric: peak muscle tension exceeds load, muscle shortens - Eccentric: peak muscle tension less than load, muscle lengthens

Select the functions of blood - It produces hormones that coordinate body activities - It collects metabolic waste from the body - It delivers oxygen and nutrients to the body - It generates cholesterol to aid cell membrane production in the body

- It collects metabolic waste from the body - It delivers oxygen and nutrients to the body

Categorize each valve of the heart as being either atrioventricular or semilunar and left or right. - Mitral valve - Tricuspid valve - Aortic valve - Pulmonary valve

- Mitral valve: left, atrioventricular - Tricuspid valve: right, atrioventricular - Aortic valve: left, semilunar - Pulmonary valve: right, semilunar

Match each definition to the appropriate muscle component. - Muscle fiber - Myofibril - Myofilament

- Muscle fiber: an individual muscle cell - Myofibril: an organelle that contains sarcomeres - Myofilament: may contain either actin or myosin

Match each definition to the appropriate term. Nor all definitions will be used. - Preload - Afterload - Venous return

- Preload: extent of cardiac muscle cell stretch before a contraction - Afterload: amount of pressure a ventricle must produce to eject blood - Venous return: amount of blood returning to the heart Not used: - amount of blood in a ventricle during diastole

Classify statements as features of either the pulmonary circulation or the systemic circulation.

- Pulmonary circulation: relatively low blood pressure, arterial blood is deoxygenated, relatively high amount of CO2 in arterial blood - Systemic circulation: relatively high blood pressure, venous blood is deoxygenated, relatively high amount of CO2 in venous blood

Identify which chamber of the heart performs each function.

- Right atrium: receives oxygen-poor blood from body - Right ventricle: pumps oxygen-poor blood to lungs - Left atrium: receives oxygen-rich blood from lungs - Left ventricle: pumps oxygen-rich blood to body

Match each description to the appropriate microscopic feature of skeletal muscles: - Sarcoplasm - Sarcolemma - Sarcoplasmic reticulum

- Sarcoplasm: cytoplasm of muscle fiber - Sarcolemma: plasma membrane of muscle fiber - Sarcoplasmic reticulum: smooth endoplasmic reticulum of muscle fiber

Classify each of the structures as containing primarily smooth, skeletal, or cardiac muscles. - Smooth muscle - Skeletal muscle - Cardiac muscle

- Smooth muscle: vein, intestine - Skeletal muscle: forearm, thigh - Cardiac muscle: heart

Match each definition to the corresponding term. - Systolic pressure -Diastolic Pressure - Pulse pressure

- Systolic pressure: arterial blood pressure during contraction of the ventricles - Diastolic pressure: arterial blood pressure during relaxation of the ventricles - Pulse pressure: the difference in blood pressure between ventricular contraction and relaxation

Which statements describe the action potential in cardiomyocytes (heart muscle cells)? - The absolute refractory period can last for about 200 ms - Depolarization stimulates voltage-gated, slow calcium channels to open - Repolarization occurs immediately after the initial depolarization - Rapid sodium influx causes the membrane to rapidly depolarize

- The absolute refractory period can last for about 200 ms - Depolarization stimulates voltage-gated, slow calcium channels to open - Rapid sodium influx causes the membrane to rapidly depolarize

Which of the following defines vasodilation? - a decrease in the diameter of the lumen of a blood vessel, causing an increase in blood pressure - an increase in sympathetic stimulation that causes the smooth muscles of a blood vessel to relax - an increase in the diameter of the lumen of a blood vessel due to the relaxation of the muscles of the vessel walls - widening of a blood vessel lumen due to smooth muscle relaxation, causing an increase in blood pressure

- an increase in the diameter of the lumen of a blood vessel due to the relaxation of the muscles of the vessel walls

Select the statements that describe the anatomical location of the heart. - inferior to the diaphragm - inferior to the lungs - anterior to the vertebral column - superior to the diaphragm

- anterior to the vertebral column - superior to the diaphragm

Which characteristics pertain to mammalian red blood cells? - biconcave to increase surface area - lack nucleus - five major types - aid in clotting blood - generate ATP anaerobically

- biconcave to increase surface area - lack nucleus - generate ATP anaerobically

Muscle cells store only enough ATP to complete a few contractions. After using up the readily available ATP, muscle cells can form additional ATP from which of the choices? - creatine phosphate - cellular respiration - glycolysis - dephosphorylation - the Calvin cycle

- creatine phosphate - cellular respiration - glycolysis

What are the effects of the baroreceptor reflex? - decreased stroke volume - vasoconstriction - vasodilation - increased heart rate

- decreased stroke volume - vasodilation

Which statements describe intercalated discs? - intercalated discs prevent direct communication between cells - intercalated discs allow synchronized contraction of cardiac muscle cells - intercalated discs contain desmosomes - intercalated discs occur in smooth muscle - intercalated discs are found between cardiomyocytes

- intercalated discs allow synchronized contraction of cardiac muscle cells - intercalated discs contain desmosomes - intercalated discs are found between cardiomyocytes

Which of these problems can cause a heart murmur? - abnormally fast heart rate - malformed heart valve cusps - premature atrial contraction - defective papillary muscles

- malformed heart valve cusps - defective papillary muscles

Which statements are true of the arteriole and venule ends of a capillary bed? - fluid moves into the capillary bed at the arteriole end - osmotic pressure at the arteriole end and the venule end are equal - net filtration pressure is higher at the arterial end than it is at the venule end - fluid moves into the capillary bed at the venule end - osmotic pressure is higher at the venule end than it is at the arteriole end

- osmotic pressure at the arteriole end and the venule end are equal - net filtration pressure is higher at the arterial end than it is at the venule end - fluid moves into the capillary bed at the venule end

Which of the actions are functions of skeletal muscle? - regulating blood vessel diameter - producing movement - pumping blood through the heart - helping to stabilize joints

- producing movement - helping to stabilize joints

Select the descriptions that refer to the physical characteristics of blood. - salty and slightly metallic in taste - amounts to approximately 4-6 liters per person - slightly acidic - red in color when well oxygenated and blue after delivering oxygen to the tissues - bright red in color when well oxygenated and dark red after delivering oxygen to the tissues

- salty and slightly metallic in taste - amounts to approximately 4-6 liters per person - bright red in color when well oxygenated and dark red after delivering oxygen to the tissues

Classify each characteristic based on whether it describes slow oxidative, fast oxidative, or fast glycolytic muscle fibers. - slow oxidative fibers - fast oxidative fibers - fast glycolytic fibers

- slow oxidative fibers: primarily use oxygen to produce ATP and have a slow contraction speed, red, low glycogen and high myoglobin stores - fast oxidative fibers: red or pink, intermediate glycogen and high myoglobin stores, primarily use oxygen to produce ATP and have a fast contraction speed - fast glycolytic fibers: high glycogen and low myoglobin stores, primarily do not use oxygen to produce ATP and have a fast contraction speed, white

Categorize the exercises according to whether they utilize isotonic or isometric contractions. -Isotonic contraction - Isometric contraction

-Isotonic contraction: pull-up, deadlift - Isometric contraction: static lunge, plank position

Place the events of excitation-contraction coupling in the sequence they occur

1. An action potential is produced in the sarcolemma 2. The action potential enters the T Tubules 3. Calcium channels in the sarcoplasmic reticulum open 4. Calcium ions flow into the sarcoplasm 5. Calcium ions bind to troponin 6. Troponin changes shape 7. Tropomyosin moves 8. Active sites are exposed on the thin filament 9. The thin and thick filaments bind

Arrange the events that take place when a motor neuron's action potential triggers a muscle contraction in sequential order, from the top down.

1. The motor neuron's action potential arrives at the neuromuscular junction 2. Acetylcholine arrives at the muscle fiber's plasma membrane, which causes the membrane to depolarize 3. The transverse (T) tubules carry the action potential throughout the muscle fiber 4. The sarcoplasmic reticulum becomes more permeable in response to the action potential, causing a release of calcium ions. 5. When the tropomyosin shifts position as calcium ions bind to troponin, actin binding sites are exposed 6. Myosin cross-bridges attach to actin fibers 7. Sarcomeres within the muscle fibers contract

Put these phases of the cardiac cycle in the correct order

1. beginning of atrial systole 2. completion of ventricular filling 3. beginning of ventricular systole 4. closure of the AV valves 5. isovolumic contraction 6. opening of the semilunar valves 7. ventricular ejection 8. ventricular relaxation

What is a normal value for systolic pressure in a healthy adult? - 111 mmHg - 72 mmHg - 156 mmHg - 39 mmHg - 25 mmHg

111 mmHg

Suppose a vessel has a blood flow rate of 19 mL/min and the pressure in the vessel drops by 39 mmHg. What is the resistance in the vessel?

2.05 mmHg * min/mL

The tube represents a centrifuged sample of blood. Use the scale provided to estimate the hematocrit value.

20%

Calculate the cardiac reserve for someone whose resting heart rate (HR) is 65 bpm and resting stroke volume (SV) is 71 mL and whose maximal HR is 179 bpm and maximal SV is 183 mL.

28.142 L/min

Suppose that an athlete has a strove volume of 80.0 mL/beat and a heart rate of 50.0 beats/min. Calculate the athlete's cardiac output.

4 L/min

If someone's blood pressure were listed as 125/75 mmHg, then their pulse pressure would be: (in mmHg)

50

If someone's blood pressure were listed as 110/65 mmHg, then their mean arterial pressure (MAP) would be: (in mmHg)

80

Suppose a person's blood pressure is 122/77 mmHg. Calculate the mean arterial pressure (MAP) for this person.

92 mmHg

Which interval would not shrink during shortening of the muscle? - A Band - I band - H Zone

A Band

Suppose that a potential blood donor has type B+ blood. Classify the recipient's blood types as compatible or incompatible

Able to receive type B+ blood: - type B+ - type AB+ Unable to receive type B+: - type A+ - type O- - type B-

Indicate whether each characteristic describes arteries or veins.

Arteries - thick walls - high elasticity - transport oxygenated blood in systemic circulation Veins - transport deoxygenated blood in systemic circulation - one-way valves - walls with little elastic tissue - low elasticity

Indicate whether each characteristic describes arteries, veins, or capillaries.

Arteries - thick, elastic walls - transport oxygenated blood in systemic circulation Veins - transport deoxygenated blood in systemic circulation - one-way valves regulate blood flow - think, fibrous, and inelastic walls Capillaries - thin, permeable walls - sphincters regulate blood flow - exchange nutrients between blood and tissues

Why would calcium deficiency limit muscle contractions? - Calcium forms cross-bridges, which connect thick filaments to thin filaments during contraction - Calcium binds to the troponin-tropomyosin complex, exposing actin's myosin-binding sites - Calcium hydrolyzes ATP, releasing energy to pull the thin filaments past the thick filaments - Calcium is released from motor neurons, stimulating an action potential in the muscle fiber

Calcium binds to the troponin-tropomyosin complex, exposing actin's myosin-binding sites

There are four pressures that influence the bulk flow of fluid across capillary walls. Match each definition to the correct pressure.

Capillary hydrostatic pressure - the force of fluid in the blood pushing against the inner capillary wall Interstitial fluid hydrostatic pressure - the force of interstitial fluid pushing against the outer capillary wall Capillary colloid osmotic pressure - the force caused by large nondiffusible molecules in the blood Interstitial fluid colloid osmotic pressure - the force caused by large nondiffusible molecules in the interstitial fluid

Give the correct sequence of events following the depolarization of transverse tubules in excitation-contraction coupling in cardiac muscle?

Depolarization of Transverse Tubules 1. Calcium ion influx through sarcolemma 2. Calcium release into sarcoplasm 3. Actin and myosin attach 4. Thin myofilaments slide toward the middle of sarcomeres

Place the structures of the intrinsic conduction system in the order in which electrical impulses pass through them.

First 1. sinoatrial node 2. atrioventricular node 3. atrioventricular bundle 4. bundle branches 5. subendocardial conducting network (Purkinje fibers) Last

A list of some of the blood vessels of the systemic circuit is provided. Arrange them in order from highest to lowest blood pressure

Highest blood pressure 1. aorta 2. small arteries 3. arterioles 4. capillaries 5. venules 6. large veins 7. inferior vena cava Lowest blood pressure

Place the scenarios in order from the highest pressure to the lowest pressure.

Highest pressure 1. left ventricle during systole 2. right ventricle during systole 3. right atrium during systole 4. right ventricle during diastole Lowest pressure

Classify the factors based on whether they cause cardiac output to increase or decrease.

Increase - increased epinephrine levels - increased blood carbon dioxide levels - increased thyroid hormone levels - nicotine - sympathetic stimulation Decrease - beta blockers - increased blood oxygen levels - vagal stimulation - parasympathetic stimulation

Classify each factor according to whether it increases or decreases the resistance in a blood vessel.

Increases resistance - turbulent blood flow - a constricted blood vessel Decreases resistance - low blood viscosity - a shorter blood vessel

Which statement accurately describes the respiratory pump? - Inhalation constricts the thoracic veins, which increases venous return - Inhalation increases the thoracic cavity space, which increases the pressure - Inhalation increases pericardial pressure, which decreases venous return - Inhalation decreases thoracic pressure, which increases venous return

Inhalation decreases thoracic pressure, which increases venous return

Place the mechanical events of the cardiac cycle in order from the start of an initial atrial systole to the start of the next atrial systole.

Initial atrial systole 1. atrial ejection 2. start of atrial diastole and ventricular systole 3. isovolumetric contraction 4. ventricular ejection 5. start of ventricular diastole 6. isovolumetric relaxation Next atrial systole

One of the primary functions of blood is to transport carbon dioxide from the tissues to the lungs. Arrange the methods of transportation in order from the method that transports the largest amount of carbon dioxide to the method that transports the smallest amount of carbon dioxide.

Largest amount 1. dissolved as bicarbonate ions 2. bound to hemoglobin 3. dissolved as carbon dioxide Smallest amount

Place the events of a sinoatrial node cell generating a pacemaker potential in order. Start when the membrane potential is most negative (-60 mV), and end when the membrane potential becomes most negative again, immediately prior to the next pacemaker potential.

Membrane potential is -60 mV 1. Voltage-gated sodium channels open 2. The membrane slowly depolarizes 3. Voltage-gated calcium channels open 4. The membrane quickly depolarizes 5. Voltage-gated potassium channels open 6. The membrane repolarizes Membrane potential returns to -60 mV

Select the statement that describes recruitment in muscle contraction. - Neurotransmitters from the synaptic terminal of a motor neuron stimulate an action potential in the muscle fiber - The contraction of muscle fibers in one muscle stimulates the contraction of antagonistic muscles in a related muscle group - An increasing number of motor neurons are connected to the muscle fiber as a muscle grows and becomes stronger - More motor neurons and larger motor units are activated to stimulate a greater number of muscle fibers for a stronger muscle contraction

More motor neurons and larger motor units are activated to stimulate a greater number of muscle fibers for a stronger muscle contraction

Arrange the components of blood in order of relative abundance.

Most abundant 1. plasma 2. red blood cells 3. buffy coat Least abundant

Place the muscle fiber types in order from most fatigable to least fatigable.

Most fatigable - fast glycolytic fiber - fast oxidative fiber - slow oxidative fiber Least fatigable

Place the layers of the pericardium in order from the most superficial layer to the deepest layer.

Most superficial 1. fibrous pericardium 2. parietal serous pericardium 3. pericardial cavity 4. visceral serous pericardium Deepest

Which statement best describes the sliding filament model of contraction? - A bands binding to I bands through cross bridges causes thin filaments to slide past thick filaments - Tropomyosin binding to troponin through cross bridges causes thin filaments to slide past thick filaments - Myosin binding to actin through cross bridges causes thin filaments to slide past thick filaments - Myofibrils binding to sarcomeres through cross bridges causes thin filaments to slide past thick filaments

Myosin binding to actin through cross bridges causes thin filaments to slide past thick filaments

Give the formula for net filtration pressure: HP = hydrostatic pressure COP = colloid osmotic pressure b = blood if = interstitial fluid

NFP = (HPb - HPif) - (COPb - COPif)

Classify statements as features of either the pulmonary circulation or the systemic circulation.

Pulmonary circulation - relatively low blood pressure - arterial blood is deoxygenated - relatively low amount of CO2 in venous blood Systemic circulation - relatively high blood pressure - arterial blood is oxygenated - relatively high amount of CO2 in venous blood

Place the events of a cardiac action potential in order, starting with the resting state.

Resting state 1. Rapid depolarization occurs as sodium channels open 2. Repolarization begins as sodium channels close 3. Repolarization slows as calcium channels open 4. Rapid repolarization occurs as calcium channels close. Resting state

What is tachycardia? - tachycardia is an interruption of action potentials in the heart - tachycardia is a heart sound caused by a valvular stenosis - tachycardia is a resting heart rate of more than 100 beats per minute - tachycardia is a persistent, abnormally slow heart rate

tachycardia is a resting heart rate of more than 100 beats per minute

During which phase of the ECG is the ventricular pressure highest? - the P wave - the T wave - the Q-T interval - the QRS complex

the Q-T interval

Which statement most accurately describes hematocrit? - the volume of plasma in a blood sample - a blood disorder - the fraction of red blood cells in a blood sample - the molecule in red blood cells that transports oxygen

the fraction of red blood cells in a blood sample

If the membranes of the cardiac muscle cells in the SA node become more permeable to potassium ions,

the heart rate will decrease

The power stroke begins when - the inorganic phosphate and ADP are released from the myosin - the actin is attached to the myosin head - the actin is released by the myosin head - the ATP is hydrolyzed by the myosin head

the inorganic phosphate and ADP are released from the myosin

What is autoregulation? - a positive feedback system that amplifies a change to the normal state within a tissue or organ - the intrinsic ability of an organ or tissue to adjust blood flow according to its needs - the intrinsic regulatory mechanism of the body that controls hormone release - the ability of the body to regulate its internal conditions despite changes to the external conditions

the intrinsic ability of an organ or tissue to adjust blood flow according to its needs

Cardiac output is equal to

the product of heart rate and stroke volume

What is hematopoiesis (hemopoiesis)? - the storage of fat - the breakdown of red blood cells - the production of blood cells - the release of minerals from bone

the production of blood cells

What does autorhythmicity (automaticity) mean? - the irregular, uncoordinated contraction of cardiac muscle - the spread of a depolarization wave throughout cardiac muscle - the stability of the cell membrane potential of contractile cardiac muscle - the spontaneous, regular depolarization and contraction of cardiac muscle

the spontaneous, regular depolarization and contraction of cardiac muscle

What does autorhythmicity (automaticity) mean? - the spread of a depolarization wave throughout cardiac muscle - the irregular, uncoordinated contraction of cardiac muscle - the stability of the cell membrane potential of contractile cardiac muscle - the spontaneous, regular depolarization and contraction of cardiac muscle

the spontaneous, regular depolarization and contraction of cardiac muscle

Severe bleeding can decrease the body's blood pressure. What mechanism causes an increase in the body's blood pressure in response to an injury? - the sympathetic nervous system causes a widening of blood vessels. - the sympathetic nervous system causes vasoconstriction - the parasympathetic nervous system causes vasoconstriction - the parasympathetic nervous system causes a widening of blood vessels

the sympathetic nervous system causes vasoconstriction

Which structure prevents blood from flowing backward in veins? - valves - venules - the tunica externa - sinuses

valves

Which factor has the greatest influence on resistance to blood flow? - blood viscosity - blood pressure - vessel diameter - vessel length

vessel diameter

What causes the heart sounds? - impact of the walls of the heart against each other during a contraction - blood flow into the ventricles following opening of the atrioventricular valves - impact of the heart valve leaflets on each other after the leaflets close - vibrations due to turbulence in blood flow following the closure of heart valves

vibrations due to turbulence in blood flow following the closure of heart valves

In which situation would the stroke volume be the greatest?

when venous return is increased

Muscles used for delicate, finely controlled movements have smaller motor units than more coarsely controlled muscles. - false - true

true

Place the steps of smooth muscle contraction in order from contraction initiation to relaxation

1. Contraction initiation 2. Smooth muscle is stimulated by an autonomic motor neuron 3. Calcium ions enter the sarcoplasm 4. Calcium ions bind calmodulin 5. Myosin light chain kinase phosphorylates myosin. 6. Actin-myosin crossbridges form 7. Contraction cycles occur 8. Myosin light chain phosphatase dephosphorylates myosin 9. Relaxation Not used: - Calcium ions bind troponin - Smooth muscle is stimulated by a somatic motor neuron

How would a decrease in venous return alter stroke volume? - stroke volume changes only when venous return increases - venous return does not affect stroke volume - stroke volume increases - stroke volume decreases

stroke volume decreases

Atherosclerosis (fat build-up in artery walls, which narrows the arteries) involves a:

sustained increase in resistance that leads to increases in arterial pressure to maintain adequate blood flow

Suppose a heart has two chambers that are connected to one another. The blood pressure in chamber A is 50 mmHg, and the blood pressure in chamber B is 50 mmHg. There is no valve in this scenario. In which direction will blood flow? - from chamber B to chamber A - there is no way to know - from chamber A to chamber B - there is no net blood movement

there is no net blood movement

What is the function of elastic arteries? - to constrict and aid in the regulation of blood flow to specific tissues - to act as a reservoir for blood returning to the heart from the capillaries - to connect muscular arteries to capillary beds and maintain capillary pressure - to help maintain relatively constant blood pressure as the heart beats

to help maintain relatively constant blood pressure as the heart beats

What is the function of arterioles? - to collect blood from capillary beds and feed into venous return - to receive blood from the heart as it is pumped out of the ventricles - to regulate blood flow to capillaries - to provide a large surface area for the diffusion of substances

to regulate blood flow to capillaries

Cardiac muscle cannot undergo tetanus because its absolute refractory period lasts almost as long as the muscle twitch. - true - false

true


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