phys2test3part2

Question 1

What does satiety mean?

Answer 1

Desire for food is satisfied.

Question 2

With metabolism the hypothalmus receives input from where?

Answer 2

GI, CNS, Adipose.

Question 3

What part of the hypothalamus is the feeding center?

Answer 3

Lateral nuclei.

Question 4

What will the feeding center or lateral nuclei of the hypothalamus do?

Answer 4

Drives search for food.

Question 5

What happens when the lateral nuclei or feeding center of the hypothalamus is stimulated?

Answer 5

Hyperphagia (constant hunger) and obesity.

Question 6

What happens with destruction of the lateral nuclei or feeding center of the hypothalmus?

Answer 6

Lack of desire for food.

Question 7

What part of the hypothalamus is the satiety center?

Answer 7

Ventromedial nuclei.

Question 8

What happens when the satiety center or ventromedial nuclei of the hypothalamus is stimulated or damaged?

Answer 8

Stimulated- Satiety and aphasia. Damaged- Voaracious and continued eating.

Question 9

Besides the lateral nuclei what part of the hypothalamus will control feeding?

Answer 9

Dorsomedial nuclei.

Question 10

Besides the ventromedial nuclei what part of the hypothalamus will control satiety?

Answer 10

Paraventricular nuclei.

Question 11

Modulation of feeding happens in the arcuate nucleus of the hypothalmus and is affected by what?

Answer 11

GI/adipose hormones.

Question 12

What are the 2 neurons in the arcuate nucleus of the hypothalamus?

Answer 12

POMC, Orexigenic.

Question 13

What will the POMC do?

Answer 13

Decreases intake of food and increases energy expenditure.

Question 14

What will the Orexigenic do?

Answer 14

Increases food intake and decreases energy expenditure.

Question 15

What are the hormones that regulate appetite?

Answer 15

CCK, Leptin, Insulin, Ghrelin.

Question 16

What is released from the orexigenic neurons and what will they do?

Answer 16

AGRP antagonist at melanocortin receptors to inhibit effects of alpha-MSH (Eat more). NPY- inhbits POMC firing and increases appetite.

Question 17

Defects in the signaling of the POMC pathway will do what?

Answer 17

Cause extreme obesity.

Question 18

What is the most common defect of the POMC pathway?

Answer 18

MCR-4

Question 19

What happens with excessive stimulation of the POMC pathway?

Answer 19

Anorexia and wasting.

Question 20

What are 3 of the short-term food regulation that turn eating off?

Answer 20

Oral factors, GI filling, GI hormones.

Question 21

What is a short-term food regulation that turns eating on?

Answer 21

Ghrelin.

Question 22

Where will ghrelin be released from?

Answer 22

Oxyntic cells of stomach and intestine.

Question 23

What is the glucostatic/aminostatic/lipostatic theory?

Answer 23

Low glucose/amino acids/ fatty acids= hunger and feeding. High glucose/ amino acids/ fatty acids= increased firing of the paraventricular and ventromedial nuclei which is the satiety center and decreased eating.

Question 24

What is the adipose feedback system?

Answer 24

Adipocytes—> leptin —> signals excess energy storage—-> inhibits appetite.

Question 25

In the last decade excess body fat has increased by how much?

Answer 25

30%.

Question 26

How many USA adults are overweight and how many are obses?

Answer 26

overweight- 64% and 33% are obese.

Question 27

Each 9C of excess equals what?

Answer 27

1g of fat.

Question 28

How many more adipocytes will obese people have and what are the adipocytes size like?

Answer 28

Obese people have 4 times as many adipocytes and they are 2 times the normal size.

Question 29

What is the % of body fat in females and males?

Answer 29

Females- 35% males- 25%.

Question 30

What are the causes of obesity?

Answer 30

Genes, lifestyle/diet/environment. Genes play a lesser role than the other stuff.

Question 31

A single episode of strenuous activity increases the BMR for how long?

Answer 31

Hours.

Question 32

How much energy is needed for muscular activity in an average person vs. a laborer?

Answer 32

Average person- 25-30%. Laborer- 60-70%.

Question 33

How common is an abnormal ventromedial nuclei in obese people?

Answer 33

Rare.

Question 34

What % of obese people have genetics as a related cause?

Answer 34

20-25%.

Question 35

With a BMI (body mass index) of 25-30 how many Calories less should we eat to lose weight?

Answer 35

500C/day, and increase activity.

Question 36

With a BMI (body mass index) greater than 35 how many Calories less should we eat to lose weight?

Answer 36

500-1000C/day with increased activity.

Question 37

What are sympathomimetics?

Answer 37

Drugs that decrease hunger.

Question 38

What are the problems with sympahtomimetics?

Answer 38

Cause CNS stimulation and hypertension, and adaptation occurs wo weight loss is only 5-10%.

Question 39

Surgery in obese people decreases mortality by up to what %?

Answer 39

40%.

Question 40

What % of obses people who had surgery to reverse the obesity will have a reversal of obesity?

Answer 40

75-85%.

Question 41

What type of obese people are candidates for surgery?

Answer 41

Those with BMI above 40 or above 35 with DM or HTN.

Question 42

What are the health effects of surgery on obses people?

Answer 42

Nutritional deficiency.

Question 43

What is inanition?

Answer 43

Starvation.

Question 44

What is anorexia?

Answer 44

Reduction in food intake caused by central neural processes.

Question 45

What is Cachexia?

Answer 45

Metabolic increased energy expenditure.

Question 46

What is the wasting syndrome of AIDS and cancer?

Answer 46

Cachexia.

Question 47

What is starvation?

Answer 47

Depletion of food stores in body tissues.

Question 48

What will the body use for energy in starvation?

Answer 48

CHO.

Question 49

How much glycogen is stored in the body and where is it at?

Answer 49

Only few 100g stored as glycogen in liver/muscles. Enough energy for 1/2 day.

Question 50

What is the problem with using fat for energy?

Answer 50

Fat makes ketones that can cross the BBB and cause ketosis.

Question 51

With starvation how are proteins consumed?

Answer 51

rapid depletion at first and then slowed depletion until fat store is depleted, and there will be a rapid depletion before death.

Question 52

With starvation what happens to water soluable vitamins?

Answer 52

They are depleted in several weeks.

Question 53

What is metabolism?

Answer 53

All bodily chemical reactions.

Question 54

What is metabolic rate?

Answer 54

Rate of heat liberation of bodily chemical reactions.

Question 55

What is a Calorie?

Answer 55

A unit of energy released from foods or expended by bodily processes.

Question 56

1 calorie will raise 1g of water how many degrees?

Answer 56

1 degree C.

Question 57

1 calorie = 1000 calories = 1 kilocalorie which equals what?

Answer 57

Unit of metabolism.

Question 58

How many calories will a man in bed all day need?

Answer 58

1650 calories.

Question 59

How many calories will a man in bed and eating need a day?

Answer 59

1850 calories.

Question 60

How many calories will a man sitting in a chair all day need?

Answer 60

2250 calories.

Question 61

Physical activity increases energy expenditure by how much?

Answer 61

25%.

Question 62

Walking stairs takes how much more energy than lying in bed?

Answer 62

17 times.

Question 63

A laborere uses how many calories a day?

Answer 63

6000-7000 calories a day.

Question 64

What is the BMR (basal metabolic rate)?

Answer 64

Minimum energy expenditure for body to exist.

Question 65

Skeletal muscle uses how much of the BMR?

Answer 65

20-30%.

Question 66

What will thyroxine do to the BMR?

Answer 66

Increase it 50-100%. While a loss of thyroxine can decrease BMR 40-60%.

Question 67

What will testosterone do to the BMR?

Answer 67

Increase it 10-15%.

Question 68

What will GH do to the BMR?

Answer 68

Increase it 15-20%.

Question 69

What will a fever do to the BMR?

Answer 69

Increase it 120% for every 10 degrees C.

Question 70

What will sleep do to the BMR?

Answer 70

Decrease it 10-15%.

Question 71

What will malnutrition do to the BMR?

Answer 71

Decrease it 20-30%.

Question 72

What will the skin temperature be?

Answer 72

the surface varies with temperature of surroundings.

Question 73

What is the normal core temperature?

Answer 73

97-99.5 degrees F.

Question 74

What is the average body temperature?

Answer 74

98.0- 98.6 degrees F.

Question 75

What temperature will be considered extreme cold and extreme hot?

Answer 75

cold- below 96, and hot- 101-104.

Question 76

Rate of heat production is what?

Answer 76

Metabolic rate of the body.

Question 77

What makes up 60% of how heat is lost?

Answer 77

Radiation infrared heat rays, electromagnetic waves.

Question 78

How much heat is lost through conduction?

Answer 78

15%, but it requires heated air to be continually moved away from skin.

Question 79

When temperature of surroundings is greater than skin what is the only method of cooling?

Answer 79

Evaporation.

Question 80

How is sweating accomplished?

Answer 80

Anterior hypothalamus---> autonomic pathways to spinal cord----> sympathetic outflow---> sweating.

Question 81

What hormones stimulate sweating?

Answer 81

Cholinergic (Ach) and EPI/norepi.

Question 82

Epi/norepi are important stimulators of sweating glands when?

Answer 82

During excersise.

Question 83

What is the composition of sweat like?

Answer 83

Similar to plasma.

Question 84

What part of the brain will detect temperature?

Answer 84

The preoptic area of the anterior hypothalamus.

Question 85

What will help to prevent hypothermia?

Answer 85

Shivering, inhibiting sweating, vasoconstriction.

Question 86

Name 3 temperature decreasing mechanisms?

Answer 86

1. Vasodilation. 2. Sweating. 3. Decrease in heat production.

Question 87

How is vasodilation done?

Answer 87

Inhibiting sympathetic system.

Question 88

Name 3 ways to increase temperature?

Answer 88

1. Vasoconstriction. 2. Piloerection. 3. Increased heat production.

Question 89

How is vasoconstriction done?

Answer 89

Sympathetic stimulation.

Question 90

How important is piloerection in increasing temperature?

Answer 90

of little importance in humans.

Question 91

How can piloerection increase temperature?

Answer 91

Traps a layer of air for insulation next to the skin.

Question 92

What can cause a fever?

Answer 92

Brain or toxin.

Question 93

What temperature will cause heat stroke?

Answer 93

105-108 degrees F.

Question 94

What are the symptoms of heat stroke?

Answer 94

Dizziness, GI distress, vomit, delirium, LOC.

Question 95

How can brain lesions cause a fever?

Answer 95

Compression or damage to hypothalamus.

Question 96

What are febrile diseases?

Answer 96

Pyrogens: breakdown products of bacteria or tissues which causes a rise of set points of hypothalamus and recruits heat production and heat conservation and causes a fever.

Question 97

Exposure to ice water for 20-30 minutes causes death due to what?

Answer 97

Heart standstill or fibrillation.

Question 98

What cold temperature will cause death?

Answer 98

77 degrees F.

Question 99

What is frostbite?

Answer 99

Freezing of bodily surfaces.

Question 100

What is ice crystals in skin?

Answer 100

Permanent damage of cells/vessels.

Question 101

Name 4 roles of cholesterol?

Answer 101

1. Membrane component. 2. Steroid synthesis. 3. Bile acid/salt precursor. 4. Vitamin D precursor.

Question 102

Name 3 sources of cholesterol?

Answer 102

1. Diet. 2. De novo synthesis. 3. Cholesterol synthesized in extrahepatic tissues.

Question 103

What is a major dietary source (animal product) of cholesterol?

Answer 103

eggs.

Question 104

We absorbe what % of dietary cholesterol?

Answer 104

50%.

Question 105

Increased intake of dietary cholesterol equals what?

Answer 105

Decreased absorption.

Question 106

How much dietary cholesterol is excreted a day and in what form?

Answer 106

1 g/day in bile acids.

Question 107

If we assume 400 mg intake a cholesterol a day how much is absorbed and how much is excreted?

Answer 107

Absorbed-200mg. Excreted- 1000mg.

Question 108

So if we assume 400 mg cholesterol intake a day how much de novo synthesis of cholesterol is made?

Answer 108

800 mg a day.

Question 109

How will lowering cholesterol intake effect blood cholesterol?

Answer 109

Very little effect.

Question 110

Cholesterol synthesis is similar to what pathway?

Answer 110

Ketogenic.

Question 111

Where will cholesterol synthesis happen at?

Answer 111

In cytosol.

Question 112

What is needed for cholesterol synthesis?

Answer 112

NADPH and ATP.

Question 113

How regulated in cholesterol synthesis?

Answer 113

It is highly regulated.

Question 114

What areas of the body will cholesterol be synthesized at?

Answer 114

80% in liver, 10% in intestines, 5% in skin.

Question 115

What is HMG CoA reductase used for?

Answer 115

Enzyme used in synthesis of cholesterol.

Question 116

How many enzymes are used in synthesis of cholesterol?

Answer 116

Many.

Question 117

What is the short term regulation of HMG CoA reductase?

Answer 117

Inhibited by phosphorylation.

Question 118

HMG CoA reductase is phospharylated and made active by ATP so when ATP is low what happens?

Answer 118

The body wont waste energy on cholesterol synthesis and wont phospharylate the HMG CoA reductase.

Question 119

What is proteolysis and how will it be a long term regulation of HMG CoA reducatse?

Answer 119

It is breaking down of proteins into smaller substances.

Question 120

What will cholesterol and cholesterol metabolites do to HMG CoA reducatse?

Answer 120

It has a negative feedback and will cause a long term regulation of HGM CoA reductase.

Question 121

What will SREBP-2 and SREBP-1c do?

Answer 121

These both are transcriptional regulations of cholesterol synthesis. SREBP-2= mainly regulates cholesterol synthesis. SREBP-1c= mainly regulates fatty acid synthesis.

Question 122

Transcriptional regulation of cholesterol synthesis responds to cellular levels of what?

Answer 122

Sterols.

Question 123

What happens when sterol levels are low?

Answer 123

SREBP-2 is released.

Question 124

How will statins decrease cholesterol?

Answer 124

By decreasing HMG CoA reducatase activity.

Question 125

What will Bile sequestering agents do?

Answer 125

Lower cholesterol by binding bile acid and then more bile acids will need to be made from cholesterol.

Question 126

What will oat bran do to cholesterol?

Answer 126

Lower it because it is a soluable fiber.

Question 127

What will Niacin do?

Answer 127

Inhibits VLDL excretion and may cause a fatty liver, but 3-8 grams a day will lower cholesterol.

Question 128

What is RYR?

Answer 128

Red yeaste rice.

Question 129

RYR will do what?

Answer 129

Lowers cholesterol by acting like a statin and decreasing the HMG CoA reductase activity.

Question 130

Name 2 other things that will lower cholesterol?

Answer 130

Policosanols and garlic.