Ch. 41 - Animal Nutrition

Question 1

what are essential nutrients?

Answer 1

nutrients that must be obtained by diet; cannot be made by the organism itself

Question 2

what are the four types of essential nutrients?

Answer 2

-essential amino acids (8/20)
-essential fatty acids (omega 3/6)
-vitamins (micronutrient)
-minerals (cofactors)

Question 3

how do suspension feeders obtain food?

Answer 3

by filtering food particles with the use of cilia and mucus

Question 4

how do substrate feeders obtain food?

Answer 4

by living on their food - such as caterpillars

Question 5

how do fluid feeders obtain their food?

Answer 5

-by drinking: such as fluids of other animals, sap, or liquefying prey

Question 6

how do bulk feeders eat?

Answer 6

by eating meals i.e. - big pieces of food

Question 7

what is the function of the mouth?

Answer 7

ingestion & mechanical digestion of food
-some chemical digestion through salivary amylase

Question 8

what structures are found in the mouth?

Answer 8

teeth, tongue, cheeks, and lips

Question 9

what is the function of the pharynx?

Answer 9

to serve as a passageway for food and air

Question 10

what muscle type makes up the pharynx?

Answer 10

-composed of skeletal muscle = conscious control of swallowing

Question 11

what is the function of the esophagus?

Answer 11

to serve as a passageway for food only

Question 12

what muscle type makes up the esophagus?

Answer 12

smooth muscle, which means two things:
1. unconscious control of swallowing
2. pushes food using rhythmic contractions called peristalsis

Question 13

what is the function of the stomach?

Answer 13

to further break down food through mechanical and chemical digestion

Question 14

what is the structure of the stomach?

Answer 14

LOTS of smooth muscle, with epithelial cells specialized to produce gastric juice

Question 15

what are the three main components of gastric juice?

Answer 15

1. HCl
2. pepsinogen
3. mucus [protects stomach lining]

Question 16

what is the function of HCl in stomach acid / gastric juice?

Answer 16

to break down tissues + cell membranes, and activate pepsinogen to pepsin

Question 17

what is the function of pepsin in stomach acid / gastric juice?

Answer 17

-breaks down proteins into oligopeptides AND activates pepsinogen

Question 18

what is the function of the pancreas as an ENDOCRINE gland?

Answer 18

-secrete insulin and glucagon into the blood to regulate glucose levels

Question 19

what is the function of the pancreas as an EXOCRINE gland?

Answer 19

to secrete enzymes into the small intestine through a hole in the intestine

Question 20

what three enzymes are secreted from the pancreas and what do they digest?

Answer 20

trypsinogen [which becomes trypsin, digests proteins]
-lipase [fats]
-amylase [starch]

Question 21

what are the digestive functions of the liver?

Answer 21

-creates bile for the digestion of fats
-stores glycogen
-stores iron and fat soluble nutrients [ADEK]

Question 22

what are the two main functions of the small intestine?

Answer 22

-to absorb most of the nutrients from the eaten food
-to move food using peristalsis

Question 23

what are the three main structures in the small intestine that assist with food absorption?

Answer 23

1. ridges to increase surface area
2. villi
3. microvilli w/ brush border enzymes

Question 24

how does fat absorption differ from absorption of other monomers?

Answer 24

fat is absorbed into the lymph system instead of the blood due to its size

Question 25

where are most nutrients, except fats, absorbed in the small intestine?

Answer 25

all nutrients, except fats, are absorbed into blood vessels in the villi in their monomer forms

Question 26

what are the functions of the large intestine?

Answer 26

chemical digestion through gut flora
absorption of water
elimination of cellulose/wastes
gut motility

Question 27

what is the cecum?

Answer 27

a section of the large intestine adapted for herbivorous diets, much longer in herbivores than omnivores

Question 28

what is the microbiome?

Answer 28

all bacteria / microorganisms in the gut. play roles in digestion, metabolism, fighting infections, and lots of other things

Question 29

how does stomach size relate to organism size / diet?

Answer 29

-carnivores that eat few large meals need big stomachs
-animals without teeth [frogs] also need large stomachs
-herbivores that need to digest food for longer periods of time need a longer cecum

Question 30

what two hormones play a role in regulating blood glucose levels?

Answer 30

insulin and glucagon

Question 31

what is the function of insulin?

Answer 31

insulin presence causes the liver to store glucose as glycogen and triglycerides

Question 32

what is the function of glucagon?

Answer 32

glucagon causes the body to break down stored glycogen and release the glucose into the blood

Question 33

when is insulin released into the body?

Answer 33

when blood-glucose levels are high

Question 34

when is glucagon released into the body?

Answer 34

when blood-glucose levels are low

Question 35

what is type 1 diabetes?

Answer 35

a disorder in which the insulin secreting cells in the body are killed: the body can intake insulin, but none is present

Question 36

what is type 2 diabetes?

Answer 36

a disorder in which the body’s insulin receptors are dysfunctional and not responding to insulin: insulin is present, but the body cannot take it in