Chapter 15 Physiology Mastering A&P

Drag and drop the terms below so that the equation represents the relationship between flow, blood pressure, and impedance to flow as it is presented in your text.

Mean Arterial Pressure (MAP) ∝ [Cardiac Output × Total Peripheral Resistance]

Blood velocity is lowest in the ________.

capillaries

The net hydrostatic pressure (HP) is the hydrostatic pressure in the __________ minus hydrostatic pressure in the __________.

capillary; interstitial fluid

Where are the sensors for the arterial baroreceptor reflex located?

carotid sinus and aortic arch

Which of the following is the effect of the parasympathetic nervous system when blood pressure is too high?

decrease heart rate

Which of the following would cause vasodilation of arterioles?

decreased activity of the sympathetic nervous system

Due to the differences in opposing forces, there is net ________ occurring at the arteriolar end of most capillaries, coupled with net ________ at the venous end.

filtration, absorption

If blood pressure is increased at the arterial baroreceptors, what would happen with the activity level of the parasympathetic nervous system (PNS) and sympathetic nervous system (SNS)?

increased PNS activity and decreased SNS activity

If cardiac output increases and resistance in arterioles does NOT change, what happens to arterial blood pressure?

increases

Increased blood volume ________ blood pressure.

increases

Reabsorption of fluid into the capillary takes place at the arterial end or venous end of the capillary?

venous

Venous return to the heart is aided by the

skeletal muscle pump and the repiratory pump

Which set of changes correctly describes the baroreceptor reflex in response to increased blood pressure?

Increased vessel diameter, decreased resistance, decreased cardiac output

What effect would an increase in venous tone have on mean arterial pressure?

It would increase it by shifting blood from the veins into the arteries.

Which is the correct relationship between pressure, flow, and resistance?

Pressure ∝ Flow × Resistance

What is the role of the kidney in blood pressure regulation?

The kidney can eliminate water to decrease blood volume or it can conserve water to maintain blood volume.

What is the mechanism by which bulk flow occurs at the capillaries?

There is relatively higher hydrostatic pressure on the arterial end of the capillary and relatively higher colloid osmotic pressure on the venous end.

Which is a similarity between diffusion and transcytosis at capillaries?

They both allow substances to be exchanged between the blood and cells within tissues.

All of the following would cause an increase in blood pressure EXCEPT

a decrease in cardiac output.

Smooth muscle is present in the walls of

all vessel types except capillaries.

Blood pressure is highest in the ________ and decreases continuously as blood flows through the circulatory system, due to ________.

arteries, resistance from vessel walls

The vessels that are the main site of variable resistance in the circulatory system, and that contribute more than 60% of the total resistance, are the

arterioles.

Stretch-sensitive mechanoreceptors known as ________ are located in some artery walls.

baroreceptors

Perfusion is

blood flow through an organ.

In the capillaries, hydrostatic pressure (HP) is exerted by __________.

blood pressure

Capillary walls consist of ________, supported on a cellular matrix called ________.

endothelium, the basal lamina

Which net pressure draws fluid into the capillary?

net osmotic pressure

In order for the target tissues of the cardiovascular system to respond to changes in blood pressure, the autonomic nervous system has to be able to deliver chemical signals to the target tissues, which must be equipped with the appropriate receptors so that a response can be carried out. Which of the following neurotransmitters will play a role in the regulation of blood pressure by creating a change in cardiovascular function?

norepinephrine epinphrine acteylcholine

Capillary exchange involving movement between the endothelial cells is called the

paracellular pathway.

Each of the following factors would increase peripheral resistance except one. Identify the exception.

vasodilation

Rank each of the following phrases in the correct sequential order to demonstrate how sympathetic activity changes when blood pressure is high. Not all labels may be used.

1.BARORECEPTORS INCREASE FIRING RATE. 2.MEDULLA OBLONGATA INTEGRATES THE SIGNALS. 3.SYMPATHETIC OUTPUT DECREASES. 4.VENTRICULAR MYOCARDIUM BEATS WITH LESS FORCE. 5.CARDIAC OUTPUT DECREASES.

Order of Events for the CNS Control of the Heart and Blood Vessels Rank each of the following statements so that they occur in the correct sequential order.

Change in blood pressure ↓ Carotid and aortic baroreceptor fire ↓ Medullary cardiovascular control center integrates ↓ Sympathetic and parasympathetic neurons fire ↓ Heart and blood vessels generate response

A decrease in blood pressure at the arterial baroreceptors would result in which of the following?

an increase in heart contractility

Which of the following would reflect the typical net hydrostatic pressure (HP) at the arterial end of the capillary?

34 mm Hg

________ are also known as the pressure reservoir of the cardiovascular system.

Arteries

Which type of vessel changes most to regulate resistance to blood flow. Why?

Arterioles because of the large amount of smooth muscle in their walls.

The turbulent flow of blood causes a noise called a ________ that can be heard through the stethoscope when taking blood pressure.

Korotkoff sound

Blood pressure can be measured with a sphygmomanometer. When the display indicates diastolic pressure, what is heard through the stethoscope. Why?

Nothing is heard because blood flow is smooth through the fully open artery.

Which of the following is greater?

blood pressure when the peripheral vessels constrict

Although we often just use the term blood pressure loosely, the specific variable controlled by the body is mean arterial blood pressure. While there are non-cardiovascular variables that can affect blood pressure (e.g., blood volume), the cardiovascular variables can be adjusted very quickly to respond to sudden changes in blood pressure. Which of the following cardiovascular control factors contribute to changes in blood pressure?

force of cardiac contraction heart rate blood vessel diameter

Which organ is NOT part of the cardiovascular system and plays an important role in regulating blood pressure?

kidney

Osmotic pressure resulting from presence of plasma proteins in blood is called ________ pressure.

oncotic and colloid osmotic

The osmotic pressure created by the presence of proteins is known as ________, which is _________ in the plasma than in the interstitial fluid.

oncotic pressure, higher

The colloid osmotic pressure in the capillary is caused by __________.

proteins in the blood

The values obtained when measuring blood pressure, such as 120/80,

reflect the pressure in the major arteries during ventricular systole and diastole.

Myogenic autoregulation means that

stretched smooth muscle in a blood vessel constricts reflexively.

Compensation for decreased blood volume includes increases in

sympathetic stimulation to blood vessels, sympathetic stimulation of the heart, and water conservation by the kidneys.

During the fight-or-flight reaction, epinephrine is released from the adrenal medulla and binds to ________ receptors on the vascular smooth muscle of heart, liver, and skeletal muscle arterioles and results in ________ blood flow to these organs; epinephrine can also bind to ________ receptors on other tissues, causing ________ blood flow to these organs.

β2, increased, α, decreased

Stimulation of the adrenal medulla would result in which of the following?

an increase in heart rate and contractility

What compensatory mechanisms are available to help maintain blood pressure when a large volume of blood is lost, such as during a hemorrhage?

Vasoconstriction, increased thirst, and decreased renal fluid output in the urine

Drag and drop each of the following receptors and neurotransmitters so that it matches up with the correct tissue. Terms may be used more than once.

Ventricular myocardium: β1- receptors,Epinephrine,Norepinephrine Arteriolar smooth muscle: Epinephrine,Norepinephrine α - receptors SA node: Epinephrine, Norepinephrine, β 1- receptors, Acetylcholine, Muscarinic receptors

Bulk flow refers to the mass movement of fluid between the blood and the interstitial fluid. Which of the following statements is not correct concerning bulk flow?

In a typical capillary, overall bulk flow transitions from net absorption on the arterial end to net filtration on the venous end.

Drag and drop each of the following terms associated with the control of heart rate and blood vessel diameter so that it appropriately matches with its defining term (e.g., integrating center, receptors, and so on).

Medullary cardiovascular centres - Integrating center Parasympathetic neurons - Efferent neurons Sympathetic neurons - Efferent neurons Carotid and aortic baroreceptors - Receptors Change in blood pressure - Stimulus SA node - Target Veins - Target Arterioles - Target Ventricles - Target