Exam 2- Chapter 18

Question 1

tunica intima

Answer 1

-composed of endothelium, which provides a smooth surface
-endothelium is contious with the inner lining of the heart, endocardium
-contains internal lamina (a thin layer of subendotheial connective tissue + elastic fibers)

Question 2

tunica media

Answer 2

-composed of smooth muscle cell + external elastic lamina (elastic fibers)
-smooth muscle cells control diameter of blood vessel –> amount of blood flow to organs
-sympathetic NS controls smooth muscle cells via vasomotor nerves

Question 3

vasomotor nerves control _______ & _______

Answer 3

vasoconstriction: narrowing of diameter of blood vessel
vasodilation: increasing diameter of blood vessel

Question 4

tunica externa

Answer 4

-composed of dense irregular connective tissue
-support blood vessel and prevents it from overstretching

Question 5

vaso vasora

Answer 5

tiny vessels that supply oxygen to tunica media + extrena

Question 6

elastic arteries/conducting arteries

Answer 6

-largest diameter
-includes aorta & immediate branches
-under the highest pressure bc its closes to the heart

Question 7

muscular arteries/distributing arteries

Answer 7

-medium sized diameter
-well-developed tunica media
-regulate blood pressure

Question 8

arterioles

Answer 8

-smallest arteries
-thin wall layer

Question 9

metarterioles

Answer 9

-smallest arterioles
-controls blood flow to tissues
-feeds blood to capillary

Question 10

baroreceptor

Answer 10

receptor that detects changes in pressure

Question 11

chemorecptor

Answer 11

detects blood oxygen, carbon dioxide, + hydrogen ions concentration

Question 12

anastomoses

Answer 12

when blood vessels branch into colateral circulation that leads to same location

Question 13

arterial anastomoses

Answer 13

exist in heart, brain & around joints

Question 14

venous anastomoses

Answer 14

megiboring veins are connected by small colaterals

Question 15

capillary beds

Answer 15

location where gas exchange takes place

Question 16

precapillary sphincter

Answer 16

controls amount of blood flowing into capillary

Question 17

continous capillary

Answer 17

structure: endothelial cells + tight junction

location:
- skin
-nervous tissue
-connective tissue
-muscle tissue

function:
-least “leaky”
-few substances cross wall

Question 18

fenestration cappilary

Answer 18

structure: fenestration

location:
-kidney
-endocrine glands
-small intestine

function:
-moderate “leaky”
-allow large volume of fluids + larger substances to cross wall

Question 19

sinosudial capillary

Answer 19

structure: large pores

location:
-liver
-lymphoid organs
-bone marrow
-spleen

function:
-“leakiest”
-allow large substances (like cells) to cross wall

Question 20

venules

Answer 20

small venules –> ONLY tunica intima
large venules –> have all 3 layers of blood vessel
-drains capillary beds

Question 21

veins

Answer 21

-thin walled vessels
-large lumen
-return blood to heart

Question 22

diffusion through membrane of endothelial cells

Answer 22

carbon dixiode, oxygen, certain lipids can enter/exit capillary wall through diffusing across membrane

Question 23

diffusion + osmosis through gaps + fenestrations

Answer 23

-water + small substances (monosaccharides, amino acids) that are dissolved in water are able to move freely through pores

Question 24

transcytosis

Answer 24

-how larger molecules cross endothelial cells
endocytosis: molecules are taken in
exocytosis: molecules are moved out

Question 25

filtration

Answer 25

movement of fluid by force such as pressure or gravity

Question 26

hydrostatic pressure (HP)

Answer 26

force that fluids exert on wall blood pressure = hydrostatic pressure

Question 27

osmosis

Answer 27

movement of water from low solute concentration to high solute concentration

Question 28

osmotic pressure

Answer 28

force we must apply to solution to prevent water from moving into osmosis

Question 29

edema

Answer 29

excessive amount of water in interstitial fluid common cause: increase in HP or decrease in OP which causes SWELLING of capillary

Question 30

hemodynamics

Answer 30

physiology of blood flow in cardiovascular system

Question 31

blood pressure

Answer 31

outward force that blood exerts in walls of blood vessel

Question 32

vascular resistance

Answer 32

any impedance to blood flow

Question 33

venous return

Answer 33

blood must return ti the heart at SAME rate that is pumped into arterties -essential for noraml CO --> blood pressure

Question 34

sympathetic nervous system increases what hormones to increase blood pressure *SHORT term maintenance of HR*

Answer 34

-norepinephrine -epinephrine -which increase HR & vasoconstriction

Question 35

sympathetic nervous system increases what hormones to decrease blood pressure *SHORT term maintenance of HR*

Answer 35

-acetylcholine -decreases blood pressure by slowing HR

Question 36

sympathetic nervous system increases what hormones to increase blood pressure *LONG term maintenance of HR*

Answer 36

-antidiuretic hormone triggers thirst + increases amount of water in kidney -renin-->angiotensin ll increases thirst causing sodium ion retention -aldosterone causes sodium ion retention

Question 37

sympathetic nervous system increases what hormones to decrease blood pressure *LONG term maintenance of HR*

Answer 37

-ANP causes blood to excrete more water + sodium ions

Question 38

velocity

Answer 38

blood flow over cross-sectional area causes: velocity is slowest in arteries w high areas of cross-sectional areas