Blood Vessels

Question 1

lymphatic vascular system

Answer 1

parallels the blood capillaries, carries lymph

Question 2

lymph

Answer 2

excess tissue fluid, cellular debris, lymphocytes

Question 3

functions of blood vessels

Answer 3

gas exchange, carry nutrients to tissue, carry waste away, carry hormones, maintain quality and quantity of tissue fluid

Question 4

elastic laminae help to

Answer 4

smooth out pressure differences with distance from the heart

Question 5

flow can be controlled by

Answer 5

regulatory factors such as chemical or neural input to regulate flow to various organs

Question 6

tunica intima

Answer 6

endothelim, basement membrane, subendothelial layer of loose CT, and an internal elastic lamina (in arteries)

forms a permeable or semipermeable barrier

Question 7

tunica media

Answer 7

smooth muscle, variable amounts of elastic fibers and lamellae, reticular fibers, proteoglycans, and external elastic lamina

controls diameter and blood pressure and movement

Question 8

tunica adventitia

Answer 8

fibroblasts, longitudinal collagen and elastic fibers, vasa vasorum

provides physical support, attaches vessels to tissue and carries vessels and nerves

Question 9

endocardium

Answer 9

lines atria and ventricles. composed of an endothelium and a subendothelial layer of connective tissue

Question 10

myocardium

Answer 10

thickest layer of the heart wall and composed of cardiac muscle that is thicker in the ventricles than in the atria

Question 11

epicardium

Answer 11

forms surface of the heart and is the visceral layer of the pericardium. composed of mesothelium and the subepicardial layer of loose connective tissue that contains nerves, adipose tissue and the coronary blood vessels.

Question 12

elastic or conducting arteries

Answer 12

aorta and its main branches, physical properties produce a more uniform pressure and flow

Question 13

mixed or musculo-elastic arteries

Answer 13

parts of terminal abdominal aorta, iliac arteries, external carotids

transitional segments between elastic and muscular arteries

Question 14

muscular or distributing arteries

Answer 14

distribute blood as regulated by the autonomic nervous system

Question 15

arterioles

Answer 15

function to maintain blood pressure and reduce pressure ahead of capillaries

Question 16

changes with age

Answer 16

largest arteries grow until age 25, intima and media involved, media stiffens starting at age 30, atherosclerotic plaques in the intima, calcification of the media of muscular arteries, coronaries can be threatened by plaque by age 25

Question 17

endothelial cell cytoplasm has

Answer 17

a Golgi complex, a few mitochondria, some rough ER and free ribosomes

Question 18

endothelial cell structural support

Answer 18

provided by intermediate filaments desmin and vimentin

Question 19

endothelial cells secrete

Answer 19

a basal lamina

Question 20

endothelial cells are joined

Answer 20

by occluding (tight) and gap junctions

Question 21

endothelial cell average life span

Answer 21

150-180 days, relatively slowly renewing

Question 22

intact endothelium is nonthrombogenic and synthesizes

Answer 22

a variety of bioactive substances including types I, III, IV, and V collagens, fibronectin, laminin, coagulants, and anticoagulants

Question 23

pericytes

Answer 23

stellate cells that surround capillaries and some post capillary venules. shares basal lamina of the endothelial cells.

Question 24

continuous capillaries

Answer 24

most common type of capillary. found in muscle, nervous and CT, and the exocrine pancreas. transports large molecules.

Question 25

fenestrated capillaries

Answer 25

found in the pancreas, intestines, and endocrine glands. specialized for rapid interchange of substances between blood and tissue.

Question 26

types of sinusoids and location

Answer 26

sinusoidal capillaries found in endocrine glands, discontinuous sinusoids found in the liver and bone marrow, venous sinusoids in the spleen

Question 27

sinusoids

Answer 27

irregular blood channels that conform to the shape of the structure they line

Question 28

sinusoidal capillaries

Answer 28

have continuous basal lamina and fenestrae with diaphragms that are much larger than in fenestrated capillaries

Question 29

discontinuous sinusoids

Answer 29

have discontinuous or absent basal lamina and have large gaps between endothelial cells that permit enhanced exchange between blood and tissue.