Quick Biochemistry - Proteins And Protein Metabolism (Section 12)
1
Which of the following is an example of a scleroprotein?
Answer
(D)
Elastin
2
Which of the following is an example of a phosphoprotein?
Answer
(B)
Ovovitellin
3
Which of the following is an example of a metalloprotein?
Answer
(A)
Siderophilin
4
Which of the following is an example of a chromoprotein?
Answer
(B)
Catalase
5
What is the process that involves the removal of an amino group?
Answer
(A)
Removal
6
How are polypeptides formed from proteins?
Answer
(C)
Hydrolyzing
7
What chemical reaction is indicated when proteins react with the biuret reagent?
Answer
(B)
Peptide bonds
8
Under which of the following conditions is a disulfide bond typically not broken?
Answer
(D)
Denaturation
9
What chemical is used to separate the protein molecule of insulin into its polypeptide chains without affecting the other parts of the molecule through oxidation?
Answer
(A)
Performic acid
10
How would you best describe the relative strength of a single hydrogen bond?
Answer
(A)
Weak
11
What is the term for a regularly folded structure in which peptide bonds are arranged?
Answer
(A)
Globular proteins
12
What is the name for the regular, coiled arrangement produced by hydrogen bonding in many proteins?
Answer
(A)
a-helix
13
Despite lacking certain bonds, many globular proteins remain stable in solution. Which type of bond is mentioned as a stabilizing factor?
Answer
(D)
Disulphide bonds
14
Approximately how many amino acids are in each complete turn of an alpha-helix?
Answer
(D)
3.6
15
What is the distance, in nanometers, covered by one full turn of an alpha-helix?
Answer
(C)
0.54
16
Which of the following amino acids can disrupt the alpha-helix structure?
Answer
(A)
Proline
17
Which type of bond contributes to the stability of the alpha-helix structure?
Answer
(A)
Hydrogen bonds
18
What is the subunit composition of fetal hemoglobin?
Answer
(A)
Two α and two γ chains
19
When hemoglobin binds oxygen, the structure changes due to what happening with certain chains?
Answer
(A)
β-chains
20
Which of the following substances directly disrupts hydrogen bonds in the secondary and tertiary structures of proteins?
Answer
(B)
Alkalies
21
What is affected by the hydrogen bonds between peptide linkages?
Answer
(A)
Guanidine
22
How does the ability of proteolytic enzymes to break down certain denatured proteins change?
Answer
(A)
Decreases
23
What typically happens to the ability of a protein to trigger an immune response (antigenic function) after denaturation?
Answer
(B)
Changed
24
What type of denaturation occurs when a protein is severely damaged?
Answer
(C)
Irreversible denaturation
25
What type of chains are the result when the secondary and tertiary structures of egg albumin are completely disrupted by heating?
Answer
(C)
Polypeptide chains
26
In glycoproteins, how many carbohydrate units are usually present as disaccharides?
Answer
(D)
600-700
27
Which enzyme is primarily responsible for digesting milk protein in the stomachs of infants?
Answer
(D)
Rennin
28
What is the defining characteristic of achylia gastrica?
Answer
(B)
Both pepsin and HCI
29
In which condition does the pH of gastric juice typically decrease?
Answer
(B)
Pernicious anemia
30
Which amino acid(s) are peptide linkages containing the amino acid(s) are cleaved by trypsin in the small intestine?
Answer
(A)
Arginine
31
Which of the following amino acids is most likely to be found in a peptide bond cleaved by chymotrypsin in the small intestine?
Answer
(B)
Phenylalanine
32
Which amino acid is specifically targeted by Carboxypeptidase B in the small intestine when breaking down peptides?
Answer
(C)
Arginine
33
How many different active processes are involved in the active transport of amino acids?
Answer
(C)
3
34
Which category of amino acids is transported via the third active process?
Answer
(C)
Neutral amino acids
35
What cofactor is crucial for the absorption of neutral amino acids?
Answer
(A)
TPP
36
What is the impact on the absorption of one amino acid if another is consumed in excess?
Answer
(D)
Retarded
37
Approximately what percentage of ingested food proteins are typically digested under normal circumstances?
Answer
(D)
90 to 97
38
What happens to the nutritional value of cereal proteins when they are exposed to excessive heat?
Answer
(B)
Decreased
39
Within approximately how many days are more than half of the proteins in the liver and intestinal mucosa broken down and rebuilt?
Answer
(A)
10 days
40
What is the approximate half-life of an antibody protein?
Answer
(C)
2 weeks
41
Which hormone promotes the creation of new proteins?
Answer
(B)
Testosterone
42
What substance acts as a central connecting point for the metabolic processes of proteins, carbohydrates, and fats?
Answer
(A)
Oxaloacetate
43
What type of biomolecule is primarily involved in the construction and deconstruction of cellular material during metabolism?
Answer
(C)
Protein
44
When amino acids are processed in the liver and not used for building or specialized functions, what are they broken down into?
Answer
(D)
Ammonia
45
Where are excess amino acids from body tissues typically processed or transformed?
Answer
(B)
Urea
46
What is the primary role of amino acids in the creation of certain cellular building blocks?
Answer
(A)
The bases of the phospholipids
47
What term describes the metabolic processing of proteins that are consumed in excess of what the body needs?
Answer
(A)
Exogenous metabolism
48
What substance is produced when sulfur-containing amino acids are broken down and is then eliminated from the body?
Answer
(C)
H2SO4
49
From which type of amino acid is ethereal sulfate synthesized?
Answer
(D)
Sulphur containing
50
Which amino acids are essential for the body's production of creatine?
