Exam 1

Question 1

any constructive process by which simple substances are converted by living cells into more complex substances is called

Answer 1

anabolism

Question 2

chemical agents that are synthesized by particular parts of the body and are carried by blood to another part of the body where they elicit a physiological response by action on specific tissues or organs are called

Answer 2

hormones

Question 3

the physical and chemical reactions feedstuff undergoes from intake to absorption from the gut is termed

Answer 3

digestion

Question 4

what converts pepsinogen into its active form pepsin

Answer 4

HCl

Question 5

list all the nutrient classes

Answer 5

protein lipids minerals carbohydrate vitamins water

Question 6

the movement of nutrients from the GI tract through the gut wall into the lymph system, blood stream, and cells is called

Answer 6

absorption

Question 7

biocatalysts, secreted by living cells, which activate and/or accelerate chemical reactions are called

Answer 7

enzymes

Question 8

what scientific discipline has contributed the most to our understanding of nutrition

Answer 8

chemistry

Question 9

there is a factor necessary for life that many people mistakenly call a nutrient. this factor is a property that is present in several nutrients and is one of the main reasons for using higher grain levels in many diets. this important factor is called

Answer 9

energy

Question 10

____ are involved in enzyme activation

Answer 10

cofactor

Question 11

What is the difference between a concentrate and a roughage?

Answer 11

concentrate has 18% crude fiber

Question 12

On a dry, fat-free basis, what is the ratio of protein to ash in the animal body?

Answer 12

80:20 = 4:1

Question 13

Roughage diets must be supplemented with ____ while concentrate diets must be supplemented with ____

Answer 13

phosphorous; ca & p

Question 14

How do the following change (on as-is basis and less the contents of the digestive tract) as an animal (ex: cow) grows from 100 to 1000 pounds (increase or decrease)?

• water content of the carcass ___ with an increase in weight
• fat content of the carcass ___ with an increase in body weight

Answer 14

-decrease; increase

Question 15

Plants make carbohydrate, fat, an proteins from H2O, nitrates and mineral salts T/F:

Answer 15

False

Question 16

All life processes originate from the plant kingdom T/F:

Answer 16

True

Question 17

Plants and animals contain the same substances in the same proportion T/F:

Answer 17

False

Question 18

Carbohydrate is the primary constituent of animal body and it is found only in traces in plants T/F:

Answer 18

False

Question 19

Energy is stored as ____ in plants and largely as ___ in animals

Answer 19

carbs; fats

Question 20

In animals, primary nutrient responsible for structural support is ____ while ___ perform similar functions in plants

Answer 20

protein; cellulose

Question 21

As plants mature, nutrient content and other characteristics change. For the following, place a check mark in the column of the type of plant that is HIGHEST for the nutrient or characteristic in question: (mature plant/young plant)
DM yield per unit of land
digestibility %
crude fiber %

Answer 21

DM yield: mature
digestibility: young
crude fiber: mature

Question 22

In the proximate analysis of a feedstuff, what is the residue called that remains after all the combustible material has been burned?

Answer 22

Ash

Question 23

List 3 functions which the GI tract performs

Answer 23

absorbs; excretes; transports

Question 24

Enzyme Substrate Organ

a. Amylase ________ _________
b. _______ protein _________
c. lipase ________ _________
d. trypsin ________ _________

Answer 24

a. amylase; starch; mouth
b. pepsin; protein; stomach
c. lipase; fats; pancreas
d. trypsin; protein; small intestine

Question 25

List the 4 divisions of the non ruminant stomach and indicate whether or not each region is glandular

Answer 25

a. esophageal: nonglandular
b. cardiac: glandular
c. fundic: glandular
d. pyloric: nonglandular

Question 26

Rank the following with regard to the complexity of the GI tract (3 = most complex 1 = least complex)

a. carnivore
b. omnivore
c. herbivore

Answer 26

carnivore = 1
herbivore = 3

Question 27

poultry have no teeth to perform the mechanical aspects of feed breakdown; what part of GI does this?

Answer 27

gizzard

Question 28

name 3 hormones that are involved in digestive process

Answer 28

gastrin; secretin; CCK

Question 29

where is bile secreted and what is the role of bile in digestion

Answer 29

liver; emulsify fats

Question 30

Absorption is a function of surface area because the absorption occurs at the interface of the interstitial tissue and the chime. What are the fingerlike projections called that serve to greatly increase the surface area and thus absorption?

Answer 30

villi or microvilli

Question 31

What two sections of the GI tract to hind gut fermenters ferment feedstuffs

Answer 31

cecum; large intestine

Question 32

List in order the parts of the ruminant stomach

rumen; reticulum; omasum; abomasum

Answer 32

1. rumen
2. reticulum
3. omasum
4. abomasum

Question 33

In the fund region of the stomach, both acid and enzymes are secreted. One of these digestive secretions is secreted by chief cells and one by parietal cells. list the secretions of the chief and parietal cells

Answer 33

chief: pepsinogen precursor
parietal: HCl

Question 34

Why are phytase (exogenous enzyme) supplemented in non ruminant animal diets?

Answer 34

because they do not make enough on their own

Question 35

The most commonly used exogenous enzyme in swine diets is phytase. What is the main substrate for phytase?

Answer 35

Corn

Question 36

List 3 of the 5 properties of water we discussed in class

Answer 36

• high specific heat
• high surface tension
• high thermal conductivity

Question 37

List 3 sources of body water

Answer 37

• free source
• water in food
• metabolism