Section 1 of Nutrition, Digestion, Absorption, and Homeostasis TEST

Question 1

Essential amino acid

Answer 1

Cannot be replaced or synthesized by the body, so must be ingested in the diet

Question 2

Examples of essential amino acids

Answer 2

water, minerals, some vitamins, some unsaturated fatty acids, some amino acids

Question 3

Non-Essential amino acids

Answer 3

Can be synthesized by the body or have a replacement nutrient which serves same dietary purpose, so are not necessary in the diet

Question 4

Examples of non-essential amino acids

Answer 4

Carbohydrates/sugars/ starches, other minerals and some vitamins, saturated fatty acids, some amino acids

Question 5

Dietary Fiber

Answer 5

Dietary fiber is also necessary, though is not absorbed so it is technically not a nutrient.

Question 6

What is the function of dietary fiber?

Answer 6

Fiber helps prevent constipation/ cancer/ heart attacks, as well as reduces hunger, and aids in the movement of food through the digestive tract (alimentary canal)

Question 7

Malnutrition

Answer 7

A health condition that is caused by a deficiency, imbalance, or excess nutrients in the diet

Question 8

Why must food be digested?

Answer 8

Macromolecules must be hydrolyzed so they are small enough to be absorbed to pass through cell membranes in your digestive tract and into your bloodstream (so you
receive “nutrients”

Question 9

What are the causes of PKU?

Question 10

If IB states “digestion” what do they actually mean?

Answer 10

chemical digestion

Question 11

Where does most chemical digestion occur?

Answer 11

the small intestine

Question 12

Where does most absorption occur?

Answer 12

the small intestine

Question 13

Where does protein digestion begin?

Answer 13

In the stomach

Question 14

Fiber content correlation

Answer 14

the rate of material movement through the intestine is positively correlated with its fiber content

Question 15

What are the four major macromolecules?

Answer 15

Lipids, proteins, carbohydrates, nucleotides

Question 16

What is the function of microvilli?

Answer 16

Ruffling of epithelial membrane further increases surface area

Question 17

Function of rich blood supply

Answer 17

dense capillary network rapidly transports absorbed products

Question 18

Function of Single layer epithelium

Answer 18

minimizes diffusion distance between lumen and blood

Question 19

Function of Laceteals

Answer 19

absorbs lipids from the intestine into the lymphatic system

Question 20

Function of Intestinal glands

Question 21

Function of membrane proteins

Answer 21

facilitates transport of digested materials into epithelial cells

Question 22

Structure of the villus includes…

Answer 22

tight junctions, microvilli, mitochondria, pinocytotic vesicles

Question 23

Tight junctions

Answer 23

creates an impermeable barrier, keeps digestive fluids separated from tissues to ensure one-way movement

Question 24

Microvilli

Answer 24

increases the surface area of the plasma membrane, allowing more absorption to occur

Question 25

Mitochondria

Answer 25

Epithelial cells of intestinal villi will possess large numbers of mitochondria to provide ATP for active transport mechanisms

Question 26

Pinocytotic Vesicles

Answer 26

Pinocytosis (‘cell drinking) is the non-specific uptake of fluids and dissolved solutes (a quick way to translocate in bulk)

Question 27

What is the function of villi?

Answer 27

Villi increase the surface area of epithelium over which absorption is carried out

Villi absorb monomers formed by digestion as well as mineral ions and vitamins

Question 28

Function of the small intestine

Answer 28

absorbs usable food substances

Question 29

What does the large intestine absorb?

Answer 29

Water and dissolved minerals

Question 30

What structures are within the small intestine?

Answer 30

Serosa, muscle layer, submucosa, mucosa