Exercise Physiology Chapter 9 Circulatory Responses To Exercise

The primary purpose of the cardiovascular system is to _____.

The primary purpose of the cardiovascular system is to _____.

deliver adequate amounts of oxygen and remove wastes from tissues

During exercise, muscles can be supplied with more oxygen by _____.

redistribution of blood flow to the muscles from inactive organs
increased cardiac output

The arteries and veins are continuous with each other through smaller vessels. Thus, the human circulatory system is considered a(n) _____ system.

closed (loop)

The right side of the heart is separated from the left side by a muscular wall, which prevents the mixing of blood from the two sides of the heart. This muscular wall is called the _____.

interventricular septum

The heart is two pumps in one. It pumps blood via two circuits called the _____ circuits.

pulmonary and systemic

Besides transporting nutrients, the cardiorespiratory system also aids in _____.

temperature regulation and transportation of nutrients

Match the layer of the heart with its location

Epicardium - outer layer
Myocardium - middle layer
Endocardium - innermost layer

To meet the increased oxygen demands of muscle during exercise, the cardiorespiratory system must make an adjustment of blood flow by _____.

increasing cardiac output

The severity of a heart attack is determined by the _____.

number of heart cells that die

Match the type of blood vessel with its function

Arteries and arterioles - carries blood away from the heart
Veins and venules - carries blood towards the heart
Capillaries - Exchanges O2, CO2, and nutrients with tissues

Heart muscle fibers differ from skeletal muscle fibers in that heart muscle fibers are _____.

- Shorter

T/F The human heart contains four one-way valves to prevent backward movement of blood.

true.
Blood movement within the heart is from the atria to the ventricles, and from the ventricles, blood is pumped into the arteries. The human heart contains four one-way valves to prevent backward movement of blood

Match the circuits by which the blood travels with their descriptions

The pulmonary circuit - Deoxygenated blood is delivered from the right heart into the lungs through this circuit.

The systemic circuit - Oxygenated blood travels to the left side of the heart and is pumped to the various tissues of the body via this circuit.

Heart muscle fibers are all interconnected via _____.

Intercalated discs

The heart muscle that is responsible for contracting and forcing blood out of the heart is the _____.

Myocardium

When one heart fiber is depolarized to contract, all connecting heart fibers also become excited and contract as a unit. This arrangement is called _____.

functional syncytium

The type of injury that results in the death of cardiac muscle cells due to the interruption of coronary blood flow is called _____.

Myocardial infarction

A similarity between heart and skeletal muscles is that they are both _____ muscles.

Striated

T/F Unlike cardiac muscle contractions, skeletal muscle contractions are voluntary.

True.

Skeletal muscle contractions are voluntary, cardiac muscle contractions are involuntary

The contraction phase of the cardiac cycle is called ______ and the relaxation period is called ______

systole ; diastole

Which of the following allows ions to cross from one cardiac muscle fiber to another?

Intercalated discs

In the cardiac cycle, the pulmonary and aortic valves open and blood is forced into both pulmonary and systematic circulations when the _____.

ventricular pressure is greater than the atrial pressure

Heart muscle cells in the atria are separated from ventricular muscle cells by _____. Therefore, the atria contract separately from the ventricles.

a layer of connective tissue

The normal blood pressure of an adult male is _____.

180/20

Both the heart and skeletal muscles _____.

Contain the same contractile proteins

Mean arterial pressure at rest can be estimated by the formula _____.

Diastolic blood pressure + 0.33 (pulse pressure)

T/F During the cardiac cycle, atrial contraction occurs during ventricular systole.

false.
During the cardiac cycle, atrial contraction occurs during ventricular diastole.

Hypertension is classified as blood pressures above _____.

130/80 mm Hg

During diastole, the atrioventricular valves open because the _____.

ventricular pressure is lower than atrial pressure

The difference between systolic and diastolic blood pressure is called _____.

Pulse pressure

T/F The mean arterial blood pressure decreases with increases in blood viscosity and blood volume.

false.

An increase in physiological factors such as cardiac output, blood volume, resistance to flow, and blood viscosity will lead to an increase in the mean arterial blood pressure

To accurately estimate the average arterial blood pressure, systolic and diastolic blood pressure must be measured and the _____.

time spent in both systole and diastole must be known

Match the categories of hypertension with their causes

Primary hypertension - it's cause is multifactorial
Secondary hypertension - it is a result of some disease in prosess

An acute increase in arterial pressure triggers baroreceptors to send impulses to the cardiovascular control center, which responds by _____.

decreasing symphathetic activity

Spontaneous electrical activity in the normal heart is limited to a special region located in the right atrium that serves as the pacemaker for the heart. This region is called the _____.

sinoatrial node (SA node)

Identify the equation for calculating the mean arterial blood pressure.

Cardiac output x total vascular resistance

Analysis of an electrocardiogram (ECG) during exercise is often used in the diagnosis of _____.

Coronary artery disease

T/F During the cardiac cycle, atrial contraction occurs during ventricular systole

false.
During the cardiac cycle, atrial contraction occurs during ventricular diastole.

Long-term regulation of blood pressure is primarily a function of the _____.

Kidneys

During exercise in the upright position, the increase in cardiac output is due to an increase in _____.

both heart rate and stroke volume

The wave of atrial depolarization is transported by a specialized conductive tissue that radiates from a small mass of muscle tissue called the _____.

Atrioventricular node (AV node)

Even at rest, the vagus nerves carry impulses to the sinoatrial node and the atrioventricular node. This is referred to as _____.

parasympathetic tone

A recording of the electrical changes that occur in the myocardium during the cardiac cycle is called a(n) ________ (ECG).

electrocardiogram

Sympathetic fibers reach the heart by means of the ____ ____ , which innervate both the sinoatrial node (SA node) and the ventricles.

Cardiac accelerator nerves

At rest, a normal balance between parasympathetic tone and sympathetic activity to the heart is maintained by the _____.

cardiovascular control center

The variation in the time between heartbeats is referred to as _____.

Heart rate variability

Cardiac output is the product of the _____.

heart rate and stroke volume

Identify the variables that regulate stroke volume, at rest or during exercise.

- the average aortic blood pressure
- the strength of ventricular contractions
- the end-diastolic volume

The parasympathetic nervous system acts as a braking system to slow down heart rate by stimulating the _____.

vagus nerve

Regulation of venous return during exercise by the skeletal muscle pump occurs via _____.

the action of one-way valves that prevent the backflow of blood

Endings of sympathetic fibers release _____ upon stimulation, which causes an increase in both heart rate and the force of myocardial contraction during high-intensity exercise.

nonpinephrine

Impulses from various parts of the circulatory system relative to changes in important parameters are received by the cardiovascular _____, which in turn relays motor impulses to the heart in response to a changing cardiovascular need.

control center

A wide variation in resting heart rate variation (HRV) is considered to be a good index of a(n) _____.

healthy balance in autonomic regulations

The watery portion of blood that contains numerous ions, proteins, and hormones is called _____.

Plasma

The strength of ventricular contraction increases with an enlargement of the end-diastolic volume. This relationship is known as the _____.

Frank-Starling law of the heart

The flow rate of blood through the vascular system is dependent on the _____.

pressure difference across the system

The factors that regulate venous return during exercise are _____.

veconstrinction, muscle pump, respiratory pump

The most important variable in determining vascular resistance is the _____.

diameter of the blood vessel

The percentage of blood that is composed of cells is called the _____.

hematocrit

In the context of the sources of vascular resistance in the body, the primary factor regulating blood flow through organs is _____.

diameter of blood vessel

The rate of blood flow through the vascular system is inversely proportional to the _____.

vascular resistance across the system

Increased oxygen delivery to the exercising skeletal muscles is accomplished by increasing cardiac output and redistributing blood flow from the _____.

inactive organs

The increase in cardiac output during exercise in the upright position is achieved by an increase in _____.

both stroke volume and heart rate

Resistance to blood flow is directly proportional to the _____.

length of the blood vessel and the viscosity of the blood

The greatest vascular resistance in blood flow occurs in _____.

arterioles

The formula that can estimate the decrease in maximal heart rate with age in young adults is _____.

220 - age (years)

During intense exercise, the metabolic need for oxygen in skeletal muscle increases many times over the resting value. To meet this rise in oxygen demand, there should be an increase in _____.

blood flow to the contracting muscles

The relationship between cardiac output, arterial-mixed venous oxygen difference, and oxygen uptake is given by the _____.

Fick equation

In untrained or moderately trained subjects, at work rates greater than 40% to 60% VO2, the rise in cardiac output is achieved by increases in _____.

heart rate alone

During heavy or maximal exercise, there is an increase in the _____.

total coronary flow

The formula used to calculate maximal heart rate in children is _____.

208- 0.7 x age

At the beginning of exercise, the initial skeletal vasodilation that occurs is due to an intrinsic metabolic control. This type of blood flow regulation is termed _____

autoregulation

Identify the results of submaximal exercise in an emotionally charged atmosphere.

- high blood pressure
- high heart rate

VO2 is equal to the product of cardiac output and the a - VO2 difference. This relationship is called the _____.

Fick equation

During maximal exercise, the total cardiac output that goes toward contracting skeletal muscle is _____.

80% to 85%

T/F Recovery from short-term, low-intensity exercise is generally rapid.

True.

Recovery from short-term, low-intensity exercise is generally rapid. Heart rate, stroke volume, and cardiac output all decrease rapidly back toward resting levels following this type of exercise.

T/F he practical application of the double product is that this measure can be used as a guideline to prescribe exercise for patients with coronary artery blockage.

true.

The practical application of the double product is that it can be used as a guideline to prescribe exercise for patients with coronary artery blockage. This would reduce the risk of the patients developing chest pain due to a high metabolic demand on the heart.

Skeletal muscle vasodilation increases blood flow by reducing _____.

vascular resistance

At the same oxygen uptake, arm work results in _____.

higher heart rate and blood pressure

The emotional elevation in heart rate and blood pressure response to submaximal exercise in an emotionally charged atmosphere is mediated by a(n) _____.

increase in sympathetic nervous system activity

During interval training, the extent of the recovery of heart rate and blood pressure between bouts depends on the environmental conditions, the level of subject fitness, and the _____.

duration and intensity of exercise

What are the causes of cardiovascular drift?

- increasing body temperature and dehydration
- decrease in blood plasma volume

Recovery from long-term exercise is relatively slow when _____.

exercise is performed in hot and humid conditions

T/F According to the central command theory, the fine-tuning of the cardiovascular response to a given exercise test is accomplished via a series of feedback loops.

true.

According to the central command theory, the fine-tuning of the cardiovascular response to a given exercise test is accomplished via a series of feedback loops from muscle chemoreceptors, muscle mechanoreceptors, and arterial baroreceptors. The fact that there appears to be some overlap among these three feedback systems during submaximal exercise suggests that redundancy in cardiovascular control exists.

The double product, also known as rate-pressure product, is computed by multiplying heart rate times _____.

Systolic blood pressure

The relatively large increase in blood pressure during arm work is due to _____.

vasoconstriction of inactive muscle groups

If intermittent exercise is intense or the work is performed in a hot/humid environment, there is a(n)_____.

cumulative increase in heart rate and recovery is incomplete

The increase in heart rate and decrease in stroke volume observed during prolonged exercise is referred to as ___ ___

cardiovascular drift

The central command theory proposes that the initial signal to the cardiovascular system at the beginning of exercise comes from _____.

the higher brain centers