Chapter 20

Question 1

Anaerobic phase of glucose catabolism name, location, ATP yield, ends with what?

Answer 1

Glycolysis
in cell’s cytoplasm
2 ATP per glucose molecule
ends with pyruvate formation

Question 2

pyruvate manufacture, function

Answer 2

manufactured in cytoplasm during glycolysis
further metabolized in the aerobic phase
can accumulate and converted to lactate for storage (lactate will spill over to blood and go to the heart for catabolism)

Question 3

aerobic phase of glucose catabolism name location, yield

Answer 3

nutrient oxidation
in mitochondria
yield around 30 ATP per glucose
enzymes are required
end products are CO2 and H2O

Question 4

fatty/amino acid catabolism method, yield, end products, and special case

Answer 4

use only aerobic mechanisms
yield varies
broken down to ATP, H2O, CO2
*deamination (amine groups removed) before amino acids can be oxidized - this occurs in the liver and urea is formed

Question 5

functions of fiber

Answer 5

1. add bulk to stool
2. promotes toxin/waste elimination
3. slows digestion and absorption of carbs
4. provides sense of fullness
5. lowers cholesterol
6. helps prevent DM, cancer, hemorrhoids

Question 6

2 essential fatty acids and foods they are in

Answer 6

1. Linoleic acid (omega6): veggies/veggie oils (used to make prostaglandins)
2. alpha-linoleic acid (omega3): fatty fish, dark green leafy vegetables, flax seeds/soybeans/walnuts

Question 7

saturated vs unsaturated fats

Answer 7

saturated means “saturated with carbon” and has no double bonds (butter, lard, coconut oil) - 1/3 fat in diet
unsaturated has 1 or more double bonds (corn, peanut, olive oils) - both omega3&6

Question 8

trace element

Answer 8

mineral needed in very small amounts

Question 9

antioxidant and examples

Answer 9

defend against harmful effects of reactive oxygen species
ex: vit c, e, beta-carotene

Question 10

how does the body regulate conversion of nutrients for energy?

Answer 10

with controlling enzyme activity

Question 11

how many ATP per molecule is obtained between carbs, fats, and proteins?

Answer 11

carbs and proteins yield 4 kcal/g and fats yield 9 kcal/g
since fats are so energy dense, they are most efficient storage for excess calories

Question 12

what are ketone bodies and what are they used for?

Answer 12

ketone bodies are partially catabolized fatty acids produced by the liver during starvation or low carb intake OR during uncontrolled DM when low insulin tricks the liver into thinking that glucose is unavailable
they are acidic and can throw off the pH
brain tissue relies exclusively on glucose or these ketones when glucose is unavailable

Question 13

how are proteins stored in excess?

Answer 13

they are not
if in excess, they are converted to triglycerides or glucose
fats and carbs are “protein sparing” because they are used for energy first to save proteins for other functions

Question 14

marasmus

Answer 14

severe protein-energy malnutrition in infancy/childhood

Question 15

kwashiorkor

Answer 15

low protein levels; impacts toddlers when another child is born
low albumin in the blood causes ascites and eventually loss of intestinal villi, anemia, fatty substance accumulation from the liver

Question 16

bariatric surgery types and functions

Answer 16

gastric sleeve: greater curvature of stomach removed
Roux-en-Y gastric bypass: pouch created in proximal stomach & jejunum attached - bypassing duodenum
both produce less ghrelin and expose distal intestines to nutrient rich chyme increasing CCK release
have to adjust diet to get nutrients from less food

Question 17

4 mechanisms for heat loss

Answer 17

radiation (waves, no contact)
convection (promoted by cooler contacting medium)
evaporation (lost by H2O)
conduction (warm object transfers heat to cooler object with contact)

Question 18

brown fat function

Answer 18

hormones alter body temp in this fat by changing balance between metabolic outcomes
in cold: ATP production decreased which increases amount of heat produced for given amount of glucose

Question 19

where is temperature regulation controlled?

Answer 19

inn the hypothalamus
cold: constrict vessels, induce shivering, find warmer clothing
heat: dilate blood vessels, stimulate sweat

Question 20

pyrogens

Answer 20

chemicals released from immune or pathogen cells that trigger body temperature increase (fever)

Question 21

fever crisis vs lysis

Answer 21

crisis: sudden drop back to normal temp with sweating and blood vessel dilation
lysis: gradual drop back to normal temperature

Question 22

antipyretic

Answer 22

drugs that lower fever

Question 23

is it recommended to “starve a fever”?

Answer 23

no, it is actually recommended to eat a high protein diet to avoid protein destruction