Chapter 20. Blood Vessels. Saladin.

Which type of blood vessel carries blood back to the heart?

Vein

What are the three basic types of blood vessels?

arteries, veins, capillaries

_______ are microscopic, thin-walled blood vessels that connect the smallest arteries to the smallest veins.

Capillaries

The innermost layer of a blood vessel wall is the ______.

tunica interna

Which are functions of the endothelium?

Acts as selectively permeable barrier to materials entering or leaving the bloodstream

Secretes chemicals that stimulate dilation or constriction of the vessel

Repels red blood cells and platelets to retain flow

By definition, arteries are blood vessels that do which of the following?

Carry blood away from the heart

Arteries, capillaries, and veins are the three primary categories of blood __________.

vessels

Which layer of the artery wall is usually the thickest?

Tunica media

Which category includes the smallest blood vessels?

Capillaries

Which term refers to the outermost layer of vein and artery walls?

Tunica externa

The walls of arteries and veins are composed of three layers called tunics. Place the tunics in order (top to bottom), starting with the innermost layer, and ending with the outermost layer.

Tunica interna

Tunica media

Tunica adventitia

Which term refers to the small blood vessels that nourish the walls of larger vessels?

Vasa vasorum

Which acts as a selectively permeable barrier to materials moving between the capillaries and the interstitial fluid?

Endothelium

Which type of blood vessel carries blood away from the heart?

Arteries

Which of these is an artery?

B

The vasa vasorum are small vessels that comprise the blood supply to which of the following?

The walls of large blood vessels

Arrange the three classes of arteries in order from largest to smallest.

Largest: Conducting

Medium: Distributing

Smallest: Resistance

The endothelium is made of which type of epithelial tissue?

Simple squamous

Which type of artery is the largest?

conducting

True or false: Arteriosclerosis (the stiffening of arteries with age) increases the risk of aneurysms.

True

The layer of the vein wall that contains smooth muscle is called the tunica _______.

media

Which of these is a vein?

C

Arteries that are muscular or medium sized arteries that deliver blood to specific organs are called ______ arteries.

distributing

The smallest of the resistance arteries are called ______.

arterioles

Which is another name for conducting arteries?

Elastic arteries

Why is it important for conducting arteries to maintain elasticity?

Their expansion reduces systolic stress on smaller arteries.

Their expansion and recoil helps keep the blood flowing during diastole.

Their recoil helps maintain blood pressure between heartbeats.

A(n) ______ is a weak, bulging sac in the wall of an artery that pulsates with each beat of the heart and which may eventually

aneurysm

The brachial, femoral, renal, and splenic arteries are examples of ______ arteries.

distributing

Which term refers to a small vessel that empties into a capillary?

Arteriole

Which term refers to short vessels that link arterioles to capillaries?

Metarterioles

Which is an example of a sense organ found within an artery?

Carotid sinus

Which term refers to a weak, bulging point in the wall of a heart chamber or blood vessel?

aneurysm

_________ arteries deliver blood to specific organs.

distributing

The carotid sinuses are located in which blood vessels?

Internal carotid arteries

Arterioles are the smallest of which type of artery?

Resistance

Sensory signals travel from the aortic bodies to the brainstem via which cranial nerve?

Vagus nerve

In some places, short vessels called _________ link arterioles to capillaries or provide shortcuts that bypass the capillaries.

metarteriole

Arterial sense organs monitor blood chemistry and blood pressure in order to help regulate which of the following?

Respiration rate

Heart rate

Baroreceptors that monitor blood pressure are found in specialized regions of the internal carotid arteries called the carotid_______.

sinus

Where are carotid bodies located?

Near the branch of the common carotid arteries.

Sensory signals travel from the carotid bodies to the brainstem via which cranial nerve?

Glossopharyngeal nerve

Which are chemoreceptors that are located in the aortic arch?

Aortic bodies

Where does most of the exchange of nutrients, wastes, and hormones between the blood and body fluids occur?

Capillaries

Receptors in the carotid bodies that monitor O2, CO2, and pH levels are examples of which type of sensor?

Chemoreceptor

What is the function of the aortic bodies?

Monitor blood chemistry to help regulate respiratory rate

The term microvasculature (or microcirculation) refers to which of the following?

Capillaries

Arterioles

Venules

Why are capillaries sometimes called the exchange vessels of the cardiovascular system?

Most exchange between the blood and the tissue fluid occurs across capillary walls.

Which term refers to the chemoreceptors located in the carotid artery?

Carotid bodies

Which term refers to the arterioles, capillaries, and venules?

Microvasculature

True or false: The diameter of some capillaries is even smaller than the diameter of a red blood cell.

True false question.

True

The term microvasculature (or microcirculation) refers to which of the following?

Capillaries

Venules

Arterioles

The capillary wall consists of which of the following layers?

Basal lamina

Endothelium

Identify the structure labeled 'C' in the picture.

Intercellular cleft

The basal _______ is the non-cellular, proteinaceous material that surrounds the capillary endothelium and separates it from adjacent connective tissue.

lamina

The terms continuous, fenestrated, and discontinuous are used to describe the three types of what?

Capillaries

In continuous capillaries, cells called ______ contribute to vessel growth and repair by retaining the ability to differentiate into endothelial and smooth muscle cells.

pericytes

In continuous capillaries, the endothelium forms a continuous tube held together by _________ junctions

tight

Which term refers to the non-cellular, proteinacious material that surrounds the capillary endothelium and separates it from adjacent connective tissue?

Basal lamina

Match each type of capillary to its most likely location.

Continuous capillaries > Most tissues (e.g. skeletal muscle)

Fenestrated capillaries > Organs that engage in rapid absorption or filtration of small molecules (e.g. small intestine, kidneys)

Sinusoids > Areas where large proteins and cells need to enter or leave the bloodstream (e.g. liver and spleen)

Which may regulate blood flow through the capillaries, and contribute to vessel growth and repair?

Multiple choice question.

Pericytes

Which type of capillary is especially important in organs that engage in the rapid absorption or filtration of small molecules, such as the intestine and kidney?

Fenestrated

Large molecules, such as clotting proteins and albumin synthesized by the liver, enter the blood through which of the following?

Sinusoids

Arrange the three types of capillaries in order from the least permeable (only the smallest solutes can pass through) to the most permeable (largest solutes can pass through).

1/continuous capillaries

2/fenestrated capillaries

3/sinusoids

Capillaries are organized into networks called which of the following?

Capillary beds

________ capillaries are especially important in organs that engage in rapid absorption or filtration.

Fenestrated

Blood flow into capillary beds is regulated by smooth muscle structures called _________ sphincters which surround the openings to the capillaries.

precapillary

Identify the structure labeled 'A' in the picture.

Pericyte

Which are regarded as the capacitance vessels because they expand easily to accommodate an increased volume of blood?

Veins

______ are irregular blood-filled spaces in the liver, bone marrow, spleen, and some other organs.

Sinusoids

Which type of vessel receives blood from capillaries directly or by way of the distal ends of the thoroughfare channels?

Postcapillary venules

Which best defines a capillary bed?

A network of capillaries supplied by a single arteriole or metarteriole

Which of these is the smallest type of vein?

Postcapillary venules

Blood flow into capillary beds is regulated by which of the following?

Precapillary sphincters

________ venules receive blood from the postcapillary venules.

Muscular

The type of blood vessel regarded as capacitance vessels are

veins

Valves that direct blood towards the heart are formed by infoldings of which layer of the vein wall?

Tunica interna

Newly formed blood cells enter circulation from the bone marrow and lymphatic organs by passing through the walls of which of the following?

Sinusoids

______ are veins with especially thin walls, large lumens, and no smooth muscle.

Venous sinuses

_______ venules receive blood from capillaries.

post capillary

Which would be classified as large veins?

Superior venae cavae

Renal veins

Pulmonary veins

Internal jugular veins

Rank the types of veins from smallest to larges

1/postcapillary venules

2/muscular venules

3/medium veins

4/venous sinuses

5/large veins

Which term refers to a varicose vein of the anal canal?

Hemorrhoid

Which type of venule receives blood from the postcapillary venules?

Muscular

Veins have ________ that ensure the one way flow of blood.

valves

portal systems occur in which of the following?

kidneys, between the intestines and liver, between the hypothalamus and anterior pituitary.

Which type of vein is incapable of vasomotion?

Venous sinuses

Which term refers to a circulatory route in which blood flows from an artery directly into a vein, thereby bypassing the capillary?

Arteriovenous anastomosis

The venae cavae, pulmonary veins, internal jugular veins, and renal veins are classified as which of the following?

large veins

Venous anastomoses provide which of the following?

Alternative routes of drainage from an organ

Veins that have become permanently distended and convoluted due to a loss of competence of the venous valves are known as ______ veins.

varicose

An anatomical convergence where two blood vessels merge and combine their bloodstreams is known as a(n) _______

anastomosis

True or False: The femur has greater blood flow but less perfusion than the ovary.

True

Which refers to a circulatory route in which blood flows through two consecutive capillary networks before returning to the heart?

Portal system

Which term refers to all of the physical principles governing blood flow?

Hemodynamics

What is the physiological benefit of an arteriovenous shunt in the fingers and toes?

It reduces heat loss in cold weather

Arterial anastomoses provide which of the following?

Collateral routes of blood supply to a tissue

______ blood pressure is the arterial blood pressure attained during ventricular relaxation.

Diastolic

The flow of blood per given volume or mass of tissue is known as

perfusion

Hemodynamics are based mainly on which of the following?

pressure and resistance

The difference between systolic and diastolic blood pressure is called _______ (one word) pressure.

pulse