Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Cardiovascular, Pulmonary, and Hepatic Physiology > Dietary Balances > Flashcards

Dietary Balances Flashcards

1
Q

how much energy is liberated from 1 gram of carbohydrates? from fat? from protein?

A

carbohydrates: 4.1 calories
fat: 9.3 calories
protein: 4.35 calories

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what percent of carbohydrates are absorbed in the GI tract? fats? protein?

A

carbohydrates: 98%
fat: 95%
protein: 92%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is the average physiologically available energy from carbohydrates? from fat? from protein?

A

carbohydrates: 4 calories/gram
fat: 9 calories/gram
protein: 4 calories/gram

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is complete protein?

A

contains all essential amino acids in correct balance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is partial protein?

A

has an inaddequate concentration of one or more essential amimo acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what percent nitrogen is protein?

A

16%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

how can protein metabolism be determined?

A

by measuring nitrogen in urine and feces (which can be esitamed by adding 10% to urine value) and multiplying by 6.25

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

how can protein balance be determined?

A

by subtracting protein metabolized from protein intake

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is respiratory quotient?

A

the ratio of carbon dioxide output to oxygen usage (CO2/O2)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what can respiratory quotient be used to estimate? (2)

A
  1. fat utilization
    carbohydrate utilization
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the respiratory quotient for carbohydrates? for fat? for protein?

A

carbohydrates: 1
fat: 0.7
protein: 0.8

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

if measured for one hour or more, what will respiratory quotient equal?

A

will be exactly equal to repiratory exchange ratio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is one method to end up determining fat and carbohydrate metabolism?

A

determine protein metabolism by nitrogen excretion, then fat and carbohydrate metabolism can be calculated using respiratory exchange ratio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what 2 centers in the brain are responsiblle for appetite regulation?

A
  1. hunger (feeding) center
  2. satiety center
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

describe the hunger (feeding) center of the brain; where located and how operates

A

located in the lateral nuclei of the hypothalamus and operate by exciting motor that drives the animal to search for food

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what does stimulation of the hunger (feeding) center of the brain result in? what does this mean?

A

hyperphagia; eating and eating

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

describe the satiety center of the brain; where located and what it provides

A

located in the ventromedial nuclei of the hypothalamus and gives a sense of nutritional satisfaction that inhibits the feeding center

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what does stimulation of the satiety center of the brain result in? what does this mean?

A

apagia; stop eating

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what type of signals does the hypothalamus receive and from where? (4)

A
  1. nervous signals from the GI tract
  2. hormonal signals from the GI tract
  3. hormonal signals from adipose tissue
  4. signals from the cerebral cortex
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what are the 6 signalsand hormones for control of feed intake?

A
  1. stretch receptors in stomach
  2. peptide YY
  3. cholecystokinin
  4. insulin
  5. ghrelin
  6. leptin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

how do stretch receptors in the stomach control feed intake?

A

stretch receptors in the stomach activate sensory pathways in the vagus nerve that inhibit food intake

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what is peptide YY, cholecystokinin, and insulin? what do they do?

A

GI homrones that are released by ingestion of food that suppress further feeding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is ghrelin? what does it do?

A

a hormone released by the stomach, especially during fasting that stimulates appetite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is leptin? what does it do?

A

a hormone produced in increasing amounts by fat cells as they increase in size that inhibits food intake

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
what do anorexigenic mechanisms do?
decrease feeding
26
what do orexigenic mechanisms do?
increase feeding
27
what are the 2 types of neurons in the arcuate nuclei of the hypothalamus and what are they important for?
they are important as controllers of appetite/energy expenditure 1. POMC neurons 2. neurons that produce orexigenic substances (NPY-AGRP neurons)
28
what do the POMC neurons produce (2)
1. alpha-melanocyte stimulating hormone (a-MSH) 2. cocaine and amphetamine-related transcript (CART)
29
what orexigenic substances are produced by neurons in the arcuate nuclei? (2)
1. neuropeptide Y (NPY) 2. agouti-related protein (AGRP)
30
what does activation of POMC neurons do? (2)
1. decrease food intake 2. increase energy expenditure
31
what does activation of NPY-AGRPY neurons do? (2)
1. increase food intake 2. decrease energy expenditure
32
what does alpha-melanocyte stimulate hormone released by POMC neurons do?
acts on melanocortin receptors found in neurons of the paraventricular nuclei (PVN)
32
what does alpha-melanocyte stimulate hormone released by POMC neurons do?
acts on melanocortin receptors found in neurons of the paraventricular nuclei (PVN)
33
what 3 melanpcortin receptors in the PVN does alpha-melanocyte stimulating hormone released by POMC neurons act on?
1. MCR 2. MCR-3 3. MCR-4
34
what does activation of MCR, MCR-3, and MCR-4 by alpha-MSH released by POMC neurons do?
decreases food intake while increasing energy expenditure
35
what does inhibition of MCR-3 and MCR-4 so that can't bind alpha-MSH do?
greatly increases food intake and decreases energy expenditure
36
what is the hypothalamic melanocortin system important for?
important in regulating energy stores of the body
37
what does defective signaling of melanocortin pathways lead to?
extreme obesity
38
what is the result of mutations of MCR-4? (2)
1. the most common known single gene cause of human obesity 2. may account for approx 5% of early onset severe obesity in children
39
what does excessive activation of the melanocortin system do?
reduces appetite
40
what is the natural agonist of MCR-3 and MCR-4? what does it do?
AGRP released from orexigenic neurons of the hypothalamus; probably increases feeding by inhibiting the effects of alpha-MSH to stimulate melanocortin receptors
41
what are gene mutations that lead to excessive formation of AGRP in mice and humans associated with? (2)
1. increased food intake 2. obesity
42
what happens in the arcuate nucleuswhen energy stores are low? (2)
1. orexigenic neurons are activated to release NPY which stimulates appetite 2. at the same time, firing of POMC neurons is reduced, decreasing activity of the melanocortin pathway, further stimulating appetite
43
describe nervous control of the mechanical processes of feeding and what this means
salivation, licking lips, chewing, and swallowing are controlled by centers in the brain stem, so if the brain is sectioned (cut/damaged) below the hypothalamus but above the mesencephalon (midbrain) the animal can still perform mechanical feeding processes
44
how do higher brain centers influence feed intake?
areas of the amygdala (olfactory, emotions) and prefrontal cortex (decisions: get food or digest?) stimulate and inhibit feeding
45
what are the 2 main components of short-term regulation of feed intake?
1. gastrointestinal filling 2. gastrointestinal hormones
46
describe how gastrointestinal filling contributes to short-term regulation of feed intake
stretch inhibitory signals transmitted by the vagus nerve inhibit intake
47
what 4 gastrointestinal hormones contribute to short-term regulation of feed intake?
1. cholecystokinin 2. peptide YY 3. glucagon-like peptide (and insulin) 4. ghrelin
48
what does cholecystokinin do? when is it released?
released in response to fat entering the duodenum and decreases feeding by activating the melanocortin pathway
49
how is peptide YY secreted and what does it do?
secreted by the gastrointestinal tract and decreases feed intake
50
describe glucagon-like peptide's role in short term regulation of feed intake (3)
1. stimulated by food in the intestines 2. enhances insulin production 3. both glucagon-like peptide and insulin suppress appetite
51
describe insulin's role in short-term regulation of feed intake
stimulate by glucagon-like peptide, is released from the pancreas in response to high blood glucose and suppresses appetite
52
what releases ghrelin and what does it do?
ghrelin is releases from the stomach, increases with fasting, and stimulates feed intake
53
what 3 thing contribute to intermediate and long-term regulation of food intake?
1. glucostatic theory of hunger and feeding regulation 2. aminostatic and lipostatic theories of regulation 3. temperature
54
what does a decrease in blood glucose cause?
hunger
55
what does increased blood glucose cause? (2)
1. increased rate of firing of glucoreceptors in the satiety center of the ventromedial and paraventricular nuclei of the hypothalamus 2. decreases firing of glucosensitive neurons in the hunger center of lateral hypothalamus
56
what does exposure to cold do to food intake? why (2)
increases food intake 1. to increase metabolic rate since heat is a byproduct of metabolism and will warm you up 2. increases fat for insulation
57
what does exposure to heat do to food intake?
decreases food intake
58
what is leptin?
a protein hormone produced by adipocytes
59
as adipose tissue increases, what happens to the amount of leptin and its levels in the blood?
as adipose tissue increases, the amount of leptin produced by adipocytes and released into the blood increases
60
what nifty thing can leptin do?
cross the blood brain barrier to reach receptors in the hypothalamus
61
what does stimulation of leptin receptors in the hypothalamus result in? (5)
1. decreased production of NPY and AGRP 2. activation of POMC neurons 3. increased production in hypothalamus of substances (such as CRH) that decrease food intake 4. increased sympathetic nerve activity 5. decreased insulin secretion
62
what is CRH? what does it do?
corticotropin releasing hormone; stimulates the sympathetic nervous system
63
what could cause leptin resistance? (2)
1. deficient or defective leptin receptors 2. some issue in the post-receptor signaling cascade
64
what is the result of leptin resistance?
animal will continue to be stimulated to eat and will put on weight
65
what is obesity?
excess body fat
66
how is obesity measured in humans? (2)
1. body mass index, or weight in kg divided by height in m2 2. percent total body fat
67
what BMI range is overweight?
25-29.2kg/m2
68
what BMI range is obese?
>30kg/m2
69
how is percent total body fat measured? (3)
1. skin-fold thickness 2. bioelectrical impedance 3. underwater weighing
70
on the scale of percent total body fat, what is obese in men and women?
men: >25% women: >35%
71
what can happen to adipocytes in obesity?
can increase in size and number
72
what are 5 causes of obesity?
1. sedentary lifestyle 2. abnormal feeding behavior 3. childhood overnutrition 4. neurogenic abnormalities 5. genetic factors
73
what are 4 treatments for obesity?
1. decrease energy intake and increase activity 2. various drugs such as amphetamines or orlistat 3. gastric bypass surgery 4. gastric banding surgery
74
describe amphetamines as used to treat obesity (2)
1. inhibit feeding centers but people adapt so theya re addictive 2. overexcite CNS, resulting in nervousness and elevated blood pressure
75
describe orlistat as a drug to treat obesity
lipase inhibitor that reduces digestion of fat
76
what is gastric bypass surgery?
construction of a small pouch in the stomach
77
what is gastric banding surgery?
an adjustable band is placed around the stomach
78
what is inanition? (2)
1. the opposite of obesity 2. characterized by extreme weight loss
79
what is anorexia?
reduced food intake caused by diminished appetite
80
what is anorexia nervosa?
abnormal psychic state in which a person loses all desire for food and even becomes nauseated by food
81
what is cachexia?
a metabolic disorder of increased energy expenditure resulting in weight loss greater than that caused by reduced food intake alone
82
what can cause anorexia and cachexia? give 4 examples
inflammatory cytokines (TNF-a, IL-6, IL-1Beta, proteolysis-inducing factor)
83
describe what energy sources are burned in what order and speed during starvation
carbohydrates burned quickly, then fat is burned at a slower rate, and finally if starvation increases the body breaks down muscle for energy

Cardiovascular, Pulmonary, and Hepatic Physiology (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions