Bio Final Exam V

Front 1

In vertebrates, exchange of substances between the blood and the interstitial fluids occurs in the ___________.

Back 1

- capillaries

Front 2

In the cardiac cycle, when is the blood pressure at its maximum?

Back 2

- when the ventricles are contracting during systole.

Front 3

systole and diastole describe what in mammals?

Back 3

- systole = contraction
- diastole = relaxation
of the ventricles in mammals

Front 4

What does a blood pressure of 140/100 mean?

Back 4

- pressure during ventricular contraction is 140
- pressure during ventricular contraction is 100

Front 5

what are the most abundant cells in the blood?

Back 5

- erythrocytes

Front 6

what don't the mature RBCs of human not contain?

Back 6

- contain no nuclei or endoplasmic reticulum.

Front 7

How do the RBCs and WBCs differ in quantity?

Back 7

- There are at least 500 times as many red as white blood cells.

Front 8

where are RBCs generated? where are old RBCs removed?

Back 8

- in the bone marrow
- removed in the spleen

Front 9

what is the function of leukocytes?

Back 9

- to destroy foreign cells or produce antibodies

Front 10

Lifetime of an individual RBC

Back 10

120 days (4 months)

Front 11

Where is blood at its lowest pressure?

Back 11

- the capillaries

Front 12

Is the blood pressure greater or lesser than the osmotic pressure at the arterial end of the capillary bed?

Back 12

- BP is greater than osmotic pressure

Front 13

What process occurs at the arterial end of the capillary bed?

Back 13

- filtration

Front 14

What happens to the blood pressure and the osmotic potential as the blood enters the capillaries from the arterioles?

Back 14

- BP decreases
- Osmotic potential increases

Front 15

The diameter of the capillary is about the same as what?

Back 15

- a RBC

Front 16

Which blood vessels have the greatest total cross-sectional area?

Back 16

- the capillaries

Front 17

How does histamine cause inflammation?

Back 17

- makes blood vessels expand
- increases the pressure in the capillaries

Front 18

Are walls in the veins or the arteries more expandable?

Back 18

- walls of the veins are more expandable

Front 19

what causes heart murmurs?

Back 19

- sounds produced by defective heart valves

Front 20

What causes varicose veins?

Back 20

- when valves within veins can no longer prevent backflow of blood

Front 21

What mechanisms facilitate the return of venous blood to the heart

Back 21

- gravity, when veins are above the heart
- contraction of skeletal muscles
- breathing
- valves in veins

Front 22

what do precapillary sphincters do?

Back 22

- shut off the supply of blood to the capillary bed

Front 23

How does myoglobin benefit muscle cells?

Back 23

- releases bound O2 at lower PO2 conditions than hemoglobin does.

Front 24

What is internal ventilation of the gas exchange surfaces dependent on?

Back 24

- blood flow

Front 25

In the lung, there is a concentration gradient of CO2 from the erythrocyte to the ___________,
and a concentration gradient of HCO3- from the plasma to the ________.

Back 25

- CO2 from the erythrocyte to the lung
- HCO3- from the plasma to the erythrocyte

Front 26

carbonic anhydrase catalyzes a reaction between what?

Back 26

CO2 and water (to form H2CO3)

Front 27

What membrane covers the abdominal organs of the vertebrate gut?

Back 27

peritoneum

Front 28

What layer is the location of the blood and the lymph vessels in the small intestine that carry away absorbed nutrients?

Back 28

submucosa

Front 29

What activates the inactive form of stomach enzymes?

Back 29

low pH

Front 30

How does bile aid in the breakdown of lipids?

Back 30

by emulsifying the lipids

Front 31

What neutralizes the acidic chyme in the small intestine?

Back 31

bicarbonate from the pancreas

Front 32

The major function of the colon (large intestine) is

Back 32

reabsorption of water

Front 33

What typically causes the release of gastrin? what inhibits release of gastrin?

Back 33

causes release of gastrin = the presence of food in the stomach
inhibits release = low pH

Front 34

The hormone secretin is a chemical message that triggers what?

Back 34

pancreatic secretion

Front 35

when is insulin released by the pancreas?

Back 35

when blood levels of glucose rise

Front 36

factors in the movement of water into tissues?

Back 36

- osmotic gradient
- fluid pressure
- diffusion
- salinity gradient

Front 37

ammonia and urea are waste products from the metabolic breakdown of what?

Back 37

proteins

Front 38

What drives the process of filtration from the capillaries into the glomerulus?

Back 38

arterial blood pressure

Front 39

What enters Bowman's capsule from the bloodstream during filtration?

Back 39

- water
- glucose
- ions
- amino acids

Front 40

what part of the nephron functions as a counter current multiplier system?

Back 40

-loop of henle

Front 41

What % of fluid that is filtered into Bowman's capsule is reabsorbed into the blood within the kidney?

Back 41

more than 95%

Front 42

What part of the nephron reabsorbs valuable molecules such as glucose, amino acids, and vitamins?

Back 42

proximal convoluted tubule

Front 43

The kidneys help regulate the acid-base balance by controlling the level of what in the blood?

Back 43

H+ and HCO3-

Front 44

What is the effect of ADH (antidiuretic hormone)?

Back 44

- increases absorption of water
- increases blood volume
- increases urine concentration