CARDIOVASCULAR 12

Question 1

Cardiovascular responses to exercise: list 3

Answer 1

1) increase in venous return and respiratory pump
2) Increase in sympathetic activity, withdrawal of parasympathetic activity
3) Local metabolites mediate profound vasodilation in skeletal muscle (reduced TPR

Question 2

Increase in sympathetic activity, withdrawal of parasympathetic activity:

Answer 2

1) Neuromuscular junctions in skeletal muscle send signals to the CCC
2) Effects on HR + contractility, resistance arterioles in metabolically inactive tissues

Question 3

Cardiovascular responses to exercise: Three theories

Answer 3

1) Sympathetic activity cause them to think higher pressure are normal
2) Baroreceptor transmission is blocked during exercise
3) Chemoreceptor (low pH) signals outweigh baroreceptor signals

Question 4

List 2 characteristics of capillaries

Answer 4

1) Exchange materials across thin capillary wall

2) Capillary density is related to metabolic activity of cells

Question 5

Two types of capillaries

Answer 5

1) Continuous: Muscle brain

2) Fenestrated: ‘Leaky’: high

Question 6

Capillary Exchange: How do substances move?

1) Exchange between plasma and interstitial fluid can occur by?
2) Larger solutes and proteins move by transport?

Answer 6

1) Paracellular (in between cells through cell-cell junctions) pathways
2) (transcellular- through apical and bosolateral membranes of cells

Question 7

1) In most capillaries, large proteins are transported by ?

2) Small dissovled solutes, H2O, and gases move by

Answer 7

1) Transcytosis

2) Diffusion

Question 8

Capillary Exchange: final forces for transfer

1) What is Bulk flow?
2) Absorption
3) Filtration

Answer 8

1) Mass movement of fluid as a result of hydrostatic or osmotic pressure gradients
2) Fluid movement into capillaries
3) Fluid movement out of capillaries

Question 9

Filtration occurs in 2 ways?

Answer 9

1) Hydrostatic pressure

2) Net filtration at arterial end

Question 10

Solute and fluid exchange across capillaries

Answer 10

Most important means by which substances are transferred between plasma and interstitial fluid is diffusion

Question 11

1) Lipid soluble substances

2) Lipid insoluble substances

Answer 11

1) Diffuse directly through cell membrane of capillaries

2) H2O, Na+, Cl-, and glucose cross capillary walls via intercellular clefts

Question 12

What enhances diffusion across capillaries?

Answer 12

Concentration

Question 13

Effect of molecular size on passage through capillary pores

Answer 13

1) The width of capillary intercellular slit pores is 6 to 7 nanometers
2) The permeability of the capillary pores of different substances varies according to their molecular diameters
3) Capillaries in different tissues have extreme differences in their permeabilities

Question 14

Determinants of Net Fluid Movement across capillaries

1) Capillary hydrostatic pressure (Pc)
2) Interstitial fluid pressure (Pif)
3) Plasma colloid osmotic pressure (pie p/c)
4) Interstitial fluid colloid pressure (pie if)

Answer 14

1) forces fluid outward through the capillary membrane
2) Opposes filtration when valve is positive
3) Opposes filtration causing osmosis of water inward through the membrane
4) Promotes filtration by causing osmosis of fluid outward through the membrane

Question 15

1) Fluid exchange at a capillary

2) Net pressure = hydrostatic pressure

Answer 15

1) Hydrostatic pressure and osmotic pressure regulate bulk flow

Question 16

Lymphatic system: mutifunctional (3 types)

Answer 16

1) Returning fluid and proteins to circulatory system
2) Picking up fat absorbed and transferring it to circulatory system
3) Serving as filter for pathogens

Question 17

Lymphatic system (4 types)

Answer 17

1) A route by which fluid and protein can flow from interstitial spaces to the blood
2) Prevent edema
3) Lymph is derived from interstitial fluid
4) Eventually drain into the subclavian veins –> heart

Question 18

Edema: fluid buildup/swelling
Causes:

Answer 18

1) Inadequate drainage of lymph

2) Filtration&raquo_space;> absorption

Question 19

Elephantiasis?

Answer 19

Abnormal enlargement of any part of the body due to obstruction of the lymphatic channels in the area

Question 20

Causes?

Answer 20

1) Small parasitic roundworms
2) Reside in lymph channels
3) Transmitted by mosquit0
4) ~20million people wordwide

Question 21

Ascites?

Disease?

Answer 21

Fluid in the abdomen (peritoneal cavity)

Kwashiorkor

Question 22

Liver Cirrhosis

Answer 22

1) Alcoholism, Hepatitis, fatty liver disease, acetaminophen

2) Decreased function of the liver

Question 23

Capillary exchange summary

1) How many types of capillaries?
2) Which ones are variant
3) What drives filtration an absorption?
4) What is critical in the capillary and interstitium
5) What do lymphatic tissues operate to return/reclaim?

Answer 23

1) Two
2) Sinusoids are variant
3) Pressure gradients
4) Pressure concentrations
5) Return/reclaim fluid from the interstitial space