Proteins, Digestion and Absorption

Question 1

is the process by which ingested feed is broken down physically and chemically to simple products for absorption from the digestive tract.

Answer 1

Digestion

Question 2

involves the denaturing of peptide bonds and the release of free amino acids.

Answer 2

Protein digestion

Question 3

Protein-digesting enzymes are either?

Answer 3

endopeptidase or exopeptidase

Question 4

This enzyme break peptide bonds within the primary structure into smaller fragments.

Answer 4

Endopeptidases

Question 5

This enzyme cleave amino acids off the terminal end of the protein molecule.

Answer 5

Exopeptidases

Question 6

This enzyme remove an amino acid from the end with a free carboxyl group

Answer 6

Carboxypeptidases

Question 7

This enzyme act on the terminal amino acid with a free amino group.

Answer 7

aminopeptidase

Question 8

Protein digestion begins in the?

Answer 8

stomach

Question 9

This hormone, initiates the breakdown of proteins in the stomach.

Answer 9

Gastrin

Question 10

presence of food in the stomach leads to the secretion of ? by the chief cells of the gastric mucosa.

Answer 10

pepsinogen

Question 11

The presence of food in the stomach leads to the secretion of pepsinogen by ? of the gastric mucosa

Answer 11

the chief cells

Question 12

This pepsinogen turns into ?, which is active, thanks to hydrochloric acid (HCl) made by another type of cell called parietal cells.

Answer 12

pepsin

Question 13

This pepsinogen turns into pepsin, which is active, thanks to?

Answer 13

hydrochloric acid (HCl) made by parietal cells.

Question 14

What type of enzyme is pepsin?

Answer 14

Endopeptidase

Question 15

In young animals, what enzyme is released in the stomach to help clot milk, making it easier to move into the small intestine.

Answer 15

rennin

Question 16

the second stage of protein digestion occurs in the?

Answer 16

small intestine

Question 17

is a hormone released in the small intestine (duodenum) that stimulates the pancreas to release certain enzymes

Answer 17

Secretin

Question 18

Secretin is a hormone released in the small intestine (duodenum) that stimulates the pancreas to release certain enzymes, what are does inactivate form of enzymes?

Answer 18

trypsinogen, chymotrypsinogen, and procarboxypeptidase

Question 19

Another substance in the duodenum called ? activates trypsinogen, turning it into trypsin

Answer 19

enterokinase

Question 20

Another substance in the duodenum called enterokinase activates trypsinogen, turning it into?

Answer 20

trypsin

Question 21

After activation of trypsin it then then converts chymotrypsinogen and procarboxypeptidase to their active forms which are?

Answer 21

chymotrypsin and carboxypeptidase.

Question 22

What is the activated enzyme that plays a very crucial role in protein digestion in the small intestine?

Answer 22

Trypsin

Question 23

Digestion is finished off by other enzymes including ? from mucosal membranes.

Answer 23

aminopeptidases and dipeptidases

Question 24

absorption of proteins is facilitated by the?

Answer 24

villi within the small intestine into the bloodstream

Question 25

Proteins that are transported via active transport, requiring energy, and use of sodium as a kind of cotransported molecule

Answer 25

Normal free proteins

Question 26

Protein that use a direct transport method that does not require energy.

Answer 26

Whole proteins

Question 27

These organic compounds are the main type absorbed into the bloodstream

Answer 27

Free amino acids

Question 28

small chains of amino acids, like ?can also be taken in the circulatory system

Answer 28

di-, tri-, and oligopeptides

Question 29

are specific to different types of amino acids based on their characteristics, like whether they are neutral, basic, or acidic, and whether they are large or small.

Answer 29

Carrier proteins

Question 30

When our body absorbs amino acids, it prefers the ? over D-forms.

Answer 30

L-forms (the natural ones)

Question 31

could be used for tissue protein, enzyme, and hormone synthesis and deamination or transamination, and the carbon skeleton can be used for energy.

Answer 31

Absorbed amino acids

Question 32

in the hindgut are subjected to microbial fermentation leading to the production of ammonia and other polyamines.

Answer 32

Undigested proteins

Question 33

in ruminant animals, dietary proteins are classified as?

Answer 33

rumen degradable and rumen undegradable proteins

Question 34

In ruminants (like cows), the microbes in their stomach use proteins as a source of?

Answer 34

nitrogen

Question 35

Microbes need nitrogen to build their own?

Answer 35

microbial protein

Question 36

Microbes do not “care” where the nitrogen sources come from and can use nonprotein nitrogenous substances such as urea for?

Answer 36

microbial protein synthesis

Question 37

is 100% degradable in the rumen by microbial urease (can be toxic at higher levels).

Answer 37

Urea

Question 38

Urea is 100% degradable in the rumen by microbial called?

Answer 38

urease

Question 39

Protein entering the rumen may be degraded by both bacteria and protozoa, which produce?

Answer 39

proteolytic enzymes

Question 40

The rumen microbes provide ? to cleave peptide bonds in polypeptides to release the free amino acids from proteins.

Answer 40

proteases and peptidases

Question 41

Several factors such as solubility and the physical structure of protein can affect?

Answer 41

rumen degradation

Question 42

These rumen-degraded amino acids release NH3 and the C skeleton by a process called?

Answer 42

deamination

Question 43

synthesize their own microbial protein

Answer 43

rumen microbes

Question 44

which serves as a primary source of protein to the host ruminant animals.

Answer 44

microbial protein

Question 45

is enough for maintenance and survival but not for high-producing animals.

Answer 45

Microbial protein

Question 46

Ammonia absorbed from rumen is converted to urea and secreted into the blood as?

Answer 46

blood urea nitrogen (BUN)

Question 47

can be filtered and recycled to the rumen via saliva or through the rumen wall

Answer 47

Urea

Question 48

The concentration of blood urea nitrogen (BUN) in ruminants reflects the efficiency of?

Answer 48

protein utilization.

Question 49

Not all proteins are degraded in the

Answer 49

rumen

Question 50

Proteins that are not degraded by rumen microbes are called?

Answer 50

escaped, “bypassed,” or “undegradable” (rumen undegradable protein, RUP)

Question 51

have a low rumen degradation rates (e.g. proteins in corn).

Answer 51

escaped, “bypassed,” or “undegradable” (rumen undegradable protein, RUP)

Question 52

“bypassed,” or “undegradable” (rumen undegradable protein, RUP) enters the ? of the ruminant animal for digestion and absorption

Answer 52

abomasum and small intestine

Question 53

Proteins reaching the small intestine could be

Answer 53

RUP or microbial proteins

Question 54

The amino acid needs of the host animal are met by?

Answer 54

RUP and microbial proteins.

Question 55

cannot be stored within the body, so a constant dietary supply of it is necessary

Answer 55

amino acids

Question 56

Monogastric or Ruminants: The amino acid profile in the small intestine matches their diet.

Answer 56

Monogastric

Question 57

Monogastric or Ruminants: The amino acid profile in the small intestine is different from their diet.

Answer 57

Ruminants

Question 58

Monogastric or Ruminants: They cannot improve low-quality dietary protein.

Answer 58

Monogastric

Question 59

Monogastric or Ruminants: They can upgrade low-quality dietary protein.

Answer 59

Ruminants

Question 60

Monogastric or Ruminants: High-quality protein remains high-quality after digestion.

Answer 60

Monogastric

Question 61

Monogastric or Ruminants: High-quality protein can become lower in quality after digestion.

Answer 61

Ruminants

Question 62

Monogastric or Ruminants: They cannot use non-protein nitrogen sources like urea.

Answer 62

Monogastric

Question 63

Monogastric or Ruminants: They can use non-protein nitrogen sources like urea.

Answer 63

Ruminants

Question 64

Monogastric or Ruminants: A constant supply of amino acids is required for their bodily functions.

Answer 64

Both

Question 65

Among the cereal grains, this grains contain has the highest bypass potential. However, it should be noted that it is deficient in essential amino acids such as lysine and methionine.

Answer 65

corn

Question 66

Which essential amino acids are deficient in corn?

Answer 66

Lysine and methionine.

Question 67

Name two animal protein sources with high bypass potential.

Answer 67

Fish meal and meat meal.

Question 68

What processing methods increase the bypass potential of feed?

Answer 68

Drying forages and heat treatment

Question 69

tend to denature the feed protein due to the generation of heat, thereby “protecting” the protein from lysis in the rumen.

Answer 69

Feed processing methods

Question 70

sources that remain intact in the rumen and dissolve in the abomasum are commercially available.

Answer 70

Rumen protected protein