Midterm Section 3.2 - Lipids and Diabetes

Question 1

which is the only non-plant sugar?

Answer 1

lactose

Question 2

photosynthesis materials and products

Answer 2

6 water, 6 carbon dioxide –> 1 glucose, 6 oxygen

Question 3

monosaccharide structure

Answer 3

fructose - cyclo pentane, glucose/galactose - cyclohexane

Question 4

disaccharide compositions

Answer 4

sucrose - fructose + glucose
maltose - glucose + glucose
lactose - glucose + galactose

Question 5

condensation and hydrolysis

Answer 5

condensation reaction makes a bond and releases a water, hydrolysis uses a water to break a bond

Question 6

polysaccharide bonding patterns

Answer 6

glycogen has many alpha 1,6 bonds, very branched
starch has many alpha 1,4 bonds, very condensed
cellulose has beta 1,4 bonds that humans cannot digest

Question 7

salivary amylase is inactivated

Answer 7

by the pH in the stomach

Question 8

where are the enzymes for disaccharides?

Answer 8

at brush border to finish digestion of complex carbohydrates

Question 9

what is lactose intolerance? lactase persistence?

Answer 9

a reduction in production of lactase enzyme at the brush border
(gene is activated less with time)
75% of the world is lactose intolerant
lactase persistence is a gene variant in people from northern countries in the promoter region of the lactase gene

Question 10

why does lactose intertolerance lead to diarrhea symptoms?

Answer 10

lactose that gets into the colon has osmotic effect
bacteria can ferment lactose

Question 11

how is fructose metabolized?

Answer 11

in liver to glucose or fatty acids (preferential) (sucrose is fructose and glucose)
can lead to fatty liver disease and hyperlipidemia

Question 12

how does anaerobic respiration work?

Answer 12

krebs cycle cannot occur, and pyruvate cannot exit cell
pyruvate converted to lactate, which is transported to the liver to be made into glucose

Question 13

when do ketones form?

Answer 13

when krebs cycle doesn’t complete oxidation of acetyl coA and pairs them to form ketone body
ketones lead to acidosis because they are acids
glucose availability prevents ketosis

Question 14

glycogen stores

Answer 14

1% of muscle mass
about 400 kcal (1 day of fasting) total
1/3 in liver, 2/3 in muscle
highly hydrated (loss of glycogen, water loss weight loss)

Question 15

Blood glucose levels

Answer 15

homeostasis: 5-10 mmol/L
hypoglycemia - below 5 mmol/L
hyperglycemia - above 10 mmol/L

Question 16

insulin stimulates

Answer 16

uptake of glucose into cells
anabolic, storage of glycogen
conversion of excess glucose into fat

Question 17

glucagon stimulates

Answer 17

catabolic, breakdown of glycogen from liver
release of glucose into the blood

Question 18

what is glycemic index? glycemic load?

Answer 18

GI: glycemic response 50g of food/glycemic response to 50g of glucose x 100%
GL: per serving of carbs

Question 19

recommended max added sugar intake percentage and grams

Answer 19

7-10% of calories per day
225-325g of added sugar per day

Question 20

why can’t humans digest fiber?

Answer 20

because of the beta glycosidic bonds

Question 21

insoluble fiber description and benefits

Answer 21

cell walls and structural elements
cellulose, lignin and hemicellulose, resistant starch
non viscous, tough and stringy
less fermentable
benefits: cleans colon out (scraping), provides bulk
downsides: binds cations/minerals

Question 22

soluble fiber description and benefits

Answer 22

cement/glue of plants
pectin, gums, mucilages
viscous, fermentable, gummy
benefits: binds cholesterol and bile acids for recycling, improves glycemic control
downsides: decreases fat soluble vitamin absorption

Question 23

products of intestinal bacteria fermentation of fibers

Answer 23

gases: CH4, H2, CO2
SCFAs: acetate, butyric acid, propionate (acids)
provide energy for colonocytes and decrease pH

Question 24

bile reabsorption happens where?

Answer 24

terminal ileum of the SI, to be returned to the liver

Question 25

how does a high fiber diet decrease blood cholesterol?

Answer 25

a high fiber diet leads to lower bile reabsorption, increased bile synthesis from cholesterol

Question 26

AI for total fiber

Answer 26

total fiber = functional + dietary
25 g/day for women, 38 g/day for men

Question 27

fiber in vegetables per serving
fiber in fruit per serving
fiber in legumes per serving

Answer 27

2-3g per serving of 1/2 cup cooked
2g per serving - 1 medium fresh fruit, 1/2 cup berries
6-8g per serving - 1/2 cup cooked

Question 28

dental carries are caused by

Answer 28

fermentable carbs, acid producing bacteria in the mouth, susceptible tooth
sugar alcohols do not affect teeth

Question 29

types of alternative sweeteners

Answer 29

aspartame (equal, nutrasweet) - 200x sweeter than sucrose, PKU warning, heat sensitive
acesulfame-K - heat stable
sucralose (splenda) - 800x sweeter than sucrose
sugar alcohols - xylitol, mannitol, sorbitol

Question 30

sugar alcohols info

Answer 30

sugar alcohols - xylitol, mannitol, sorbitol
non fermentable, slowly absorbed
2 kcal/g

Question 31

type I vs II diabetes

Answer 31

I: autoimmune disease where immune system attacks the beta cells of the pancreas, causing decreased insulin production and glucose cannot enter cells (5-8% of diabetes)
II: in muscle or fat, insulin is binding but cells stop producing glucose transporters so signaling becomes resistant to the insulin
- initial insulin production very high, then pancreas exhausts

Question 32

fasting blood glucose and fed blood glucose pre-diabetes and diabetes
“lull”

Answer 32

fasted: pre-diabetes; 6.1-6.9 mmol/L, diabettes: above 7 mmol/L
fed: pre-diabetes: 7.8-11 mmol/L, diabetes: 11.1 mmol/L or higher
< 4mmol/L blood glucose

Question 33

osmotic diuresis

Answer 33

high glucose in blood causes dehydration and thirst because more water is needed to dilute glucose, kidney can’t keep up with glucose reabsorption (sweet urine)

Question 34

diabetes complications

Answer 34

damages blood vessels and nerves (high blood glucose increased glucose intake of tissues that don’t need as much)
kidney failure, blindness, amputations, ulcers, nerve pain

Question 35

ketosis pathway and ketone examples

Answer 35

fatty acids are converted into acetyl coA and made into ketone bodies via beta oxidation
acetone, acetoacetic acid, hydroxybutyric acid produce acetone breath

Question 36

polyuria and polydipsia

Answer 36

frequent urination and excessive thirst

Question 37

percent cardiac output to renal artery

Answer 37

25%

Question 38

symptoms of a “lull”

Answer 38

sweating, palpitations, difficulty concentrating, vision changes, drowsiness, difficulty speaking, unconsciousness

Question 39

2 processes that happen on a very low carb diet (glycogen is depleted)

Answer 39

gluconeogensis from protein and ketone production

Question 40

pros of keto, cons of keto

Answer 40

pros: increased satiety, quick weight loss, better blood glucose control, improved triglycerides/cholesterol levels
cons: low fiber, headaches, brain fog, ketone breath, difficult to stick to and no good long term data

Question 41

skim, 2% and whole milk percent energy from fat

Answer 41

2%, 30% and 50%

Question 42

glucose response to high glycemic food in healthy adult vs diabetic

Answer 42

In healthy adult healthy response is glucose rapid increase and rapid decrease whereas in unhealthy adults the glucose levels stay high (and start high)