Topic 23: Nutrition

Question 1

What are the 3 nutritional needs?

Answer 1

chemical energy - calories
organic building blocks for macromolecules
essential nutrients

Question 2

What is a Calorie?

Answer 2

heat required to raise 1 kg of water 1 degree C

Question 3

What are essential nutrients?

Answer 3

cannot be made, must be ingested

Question 4

What are the 4 types of essential nutrients?

Answer 4

essential amino acids
essential fatty acids
essential vitamins
essential minerals

Question 5

Define essential amino acids. How many do we need?

Answer 5

those we cannot synthesize - must ingest 20 total AAs requires - 8 essential in adults, 9 in infants

Question 6

What are examples of complete and incomplete proteins?

Answer 6

complete - meat, cheese, eggs, quinoa, soy, rice and beans

incomplete - some plant sources

Question 7

How many fatty acids can we synthesize? What are they essential in?

Answer 7

can synthesize many

essential in seeds, grains, veggies

Question 8

Define vitamins. What are many of them?

Answer 8

organic compounds required in small amounts (13 in humans)

many are coenzymes - required for proper enzyme function

Question 9

What are water soluble vitamins? Examples?

Answer 9

cannot be stored - excess excreted

B complex, C

Question 10

What are fat soluble vitamins? Examples?

Answer 10

can be stored

A, D, E, K

Question 11

What is vitamin C also known as? Water or lipid soluble?

Answer 11

absorbic acid

water-soluble

Question 12

What are the uses of vitamin C?

Answer 12

collagen, synthesis, antioxidant, Fe absorption

Question 13

What are the sources of vitamin C?

Answer 13

citrus, broccoli

Question 14

What happens if there’s a deficiency of vitamin C?

Answer 14

scurry
degeneration of skin, teeth, blood vessels
weakness
impaired immunity, healing

Question 15

What is vitamin A also known as? Water or lipid soluble?

Answer 15

retinol

fat-soluble

Question 16

What are the uses of vitamin A?

Answer 16

part of pigments in retina

skin maintenance

Question 17

What are some sources of vitamin A?

Answer 17

dark green veggies, dairy

Question 18

What happens if there’s a deficiency of vitamin A?

Answer 18

blindness

Question 19

What are minerals?

Answer 19

inorganic nutrients

Question 20

What are trace elements?

Answer 20

<200 mg/day
iron-hemoglobin - meats, grains, leafy greens
iodine - thyroid hormones

Question 21

How much of major minerals do we need a day?

Answer 21

> 200 mg/day

Question 22

What are some sources of major minerals?

Answer 22

calcium - bones, teeth, clotting, synapses, muscles
phosphorus - bones, teeth, ATP, NAs, phospholipids
potassium, sodium - APs, many other roles
chlorine - principle negative ion - water balance, nerves, stomach
magnesium - enzyme cofactor - muscles, nerves

Question 23

Why is appetite and consumption important?

Answer 23

critical part of homeostasis - E to do everything else

Question 24

What is an example of the regulation of appetite and consumption?

Answer 24

glucose homeostasis

malfunction -> diabetes

Question 25

What kind of disease is type 1 diabetes and how many people have it? Insulin?

Answer 25

autoimmune
10%
insulin dependence

Question 26

When do people usually develop type 1 diabetes? Insulin?

Answer 26

usually adult onset

insulin resistance

Question 27

What is ghrelin secreted by? What does it trigger?

Answer 27

secreted by the stomach
triggers hunger
“ghrelin keeps you growling”

Question 28

What does insulin triggered by?

Answer 28

triggered by an increase in blood sugar, suppresses appetite

Question 29

What does PYY do?

Answer 29

appetite suppressant from SI

Question 30

What is leptin produced by? What does it do?

Answer 30

produced by adipose tissue, suppresses appetite

responds to levels of body fat - longer term

Question 31

How does nervous system regulation work?

Answer 31

sensory neurons detect information from digestive system
-> regulates hormone secretion
hormones target satiety center in brain
generates impulses that are perceived as hungry or full

Question 32

Is the digestive system always continually active?

Answer 32

no

Question 33

How does food operate in the stomach?

Answer 33

food stretches walls
-> gastron released
-> gastric juices produced
-> churning
via enteric division of autonomic NS

Question 34

What triggers the release of . digestive hormones in the small intestine?

Answer 34

AAs, fatty acids in chyme -> trigger release of digestive enzymes

Question 35

What does cholecystokinin (CCK) do?

Answer 35

stimulates the release of pancreatic enzymes, bile

Question 36

What does secretin do?

Answer 36

stimulate the release of bicarbonate (HCO3-)
if chyme rich in fat - very high CCK, secretin
-> inhibit peristalsis, secretion of gastric juices, slows digestion