Protein Structure/Digestion & Absorption

Question 1

These proteins are generally compact, soluble, and spherical to oblate or egg-shaped.

Answer 1

Globular proteins

Question 2

These proteins are typically elongated and insolube.

Answer 2

Fibrous proteins

Question 3

What are the four levels of structure in proteins?

Answer 3

Primary structure, secondary structure, tertiary structure, quaternary structure

Question 4

It is the linear arrangement of amino acids present in the polypeptide chain.

Answer 4

Primary structure

Question 5

In this structure, each protein has a distinctive number and sequence of amino acid residues.

Answer 5

Primary structure

Question 6

This structure refers to highly regular local sub-structures.

Answer 6

Secondary structure

Question 7

It is the extended conformation of polypeptide chains.

Answer 7

Secondary structure

Question 8

What are the two most common examples of secondary structure?

Answer 8

Alpha-helix and beta-pleated sheets

Question 9

This structure refers to three-dimensional structure of a single protein molecule.

Answer 9

Tertiary structure

Question 10

It is the connectivity between two or more polypeptide chains.

Answer 10

Quaternary structure

Question 11

True or False: In quaternary structure, polypeptide chains must be identical in their primary structure.

Answer 11

FALSE. Polypeptide chains may be identical or different in primary structure.

Question 12

What type of structure is found in hemoglobin?

Answer 12

Quaternary structure

Question 13

Hemoglobin has how many subunits?

Answer 13

4 subunits (2 subunits of beta-globin, 2 subunits of alpha-globin)

Question 14

Proteins are bound together by ___, while carbohydrates are bound together by ___.

Answer 14

peptide bonds; glycosidic bonds

Question 15

What element is essential to the formation of the 20 different amino acids?

Answer 15

Nitrogen

Question 16

True or False: Protein digestion begins in the mouth.

Answer 16

FALSE. It begins in the stomach.

Question 17

Digestion breaks down proteins into ____.

Answer 17

Amino acids

Question 18

True or False: Digestion of both proteins and carbohydrates can occur in the stomach.

Answer 18

FALSE. Due to the high acidity levels of the stomach, enzymes like amylase are rendered non-functional, and no digestion of carbohydrates occurs.

Question 19

It is secreted in the stomach’s gastric acid. It attacks protein molecules, separates them, and breaks them down into amino acids.

Answer 19

Hydrochloric acid

Question 20

Enzymes function best at what pH level?

Answer 20

7.0 pH

Question 21

They are enzymes which break down proteins.

Answer 21

Proteases

Question 22

It is the only protease able to digest collagen.

Answer 22

Pepsin

Question 23

After the stomach, digestion of proteins continues in the ___.

Answer 23

Duodenum

Question 24

The pancreas helps the digestion process by secreting which two pancreatic protease enzymes?

Answer 24

Trypsin and chymotrypsin

Question 25

True or False: Protein absorption rate is faster for animal origin food than vegetarian/plant origin food.

Answer 25

TRUE

Question 26

How are nucleic acids connected to carbohydrates?

Answer 26

Nucleic acids such as RNA and DNA require the presence of pentoses ribose and deoxyribose.

Question 27

How are nucleic acids related to proteins?

Answer 27

Proteins provide the nitrogenous bases for DNA and RNA.