Biology · Chemistry

Biomolecules and Enzymes

1,432 Questions

This topic focuses on biomolecules, specifically proteins, enzymes, and amino acids. It includes questions on enzyme structures, protein folding, and catalysis. These concepts are crucial for medical and biology competitive exams.

Enzyme catalysisProtein structuresAmino acid synthesisPolypeptide chainsBiomolecule properties

Biomolecules and Enzymes Questions

Multiple choice biology simple nutrients into cells blood and its components components of blood composition of blood

Plasma protein involves in defense mechanism is 

  1. Fibrinogen

  2. Globulins

  3. Albumin

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Albumin, fibrinogen and globulin are major plasma proteins in the body.  Globulins are involved in defense mechanisms of the body. These transport ions, hormones, and lipids helping in immune function. Fibrinogens are involved in the clotting or coagulation of blood. Albumins are involved in maintaining the osmotic balance.

Thus, the correct answer is 'Globulins.'

Multiple choice biology simple nutrients into cells blood and its components components of blood composition of blood

Which of the following components are present in the plasma?

  1. Water

  2. Salt

  3. Proteins

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

One half of blood is composed of red blood cells, white blood cells and platelets which are considered as solid part of blood and another half is composed of water, salts and proteins which is the fluid part of blood. The fluid part of blood is known as plasma. Hence the components present in the plasma are water, salts and proteins.

So, the correct answer is 'All of the above'.

Multiple choice biology simple nutrients into cells blood and its components components of blood composition of blood

Most of the blood proteins are 

  1. Acidic

  2. Basic

  3. Neutral

  4. All the above in equal proportions
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Plasma is composed of 90-92% water and 6-8 % plasma proteins. Fibrinogen, globulins and albumins are the major proteins. The pH of blood is 7.35 to 7.45 slightly alkaline. Most of the blood proteins are acidic in order to neutralize the pH of blood.

So, the correct answer is 'Acidic'.

Multiple choice biology simple nutrients into cells blood and its components components of blood composition of blood

The major proteins of blood plasma are

  1. Albumin, globulin and fibrinogen.

  2. Collagen, elastin and fibrinogen.

  3. Albumin, glutelin and p-protein.

  4. Actin, myosin and tubulin.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
One half of blood is composed of red blood cells, white blood cells and platelets which are considered as solid part of blood and another half is composed of water, salts, and proteins which is the fluid part of blood. The fluid part of blood is known as Plasma. Plasma is a straw-colored, viscous fluid it has about 90-92% water and 6-8% proteins. The major proteins of blood plasma are Albumin, globulin, and fibrinogen.
So, the correct answer is 'Albumin, globulin, and fibrinogen'.
Multiple choice biology simple nutrients into cells blood and its components components of blood composition of blood

Which of these is/are inactive forms
(i) Fibrin (ii) Fibrinogen (iii) Thrombin (iv) Prothrombin (v) Thrombokinase

  1. v only

  2. i and iii only

  3. i and ii only

  4. iii and v only

  5. ii and iv only.
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Fibrinogen and prothrombin are inactive precursors (zymogens) circulating in the blood plasma that are activated during the clotting cascade.

Multiple choice biology simple nutrients into cells blood and its components components of blood composition of blood

Observe the following statements and select which are true or false?
(1) Plasma constitutes 45% of the human blood.
(2) Albumin is a plasma protein which helps in osmotic balance.
(3) Factors responsible for the blood clotting process are present in the blood.
(4) Plasma without clotting factors is called serum.
(5) Minerals are not generally found in blood.

  1. Only 5 is wrong and all others 1 to 4 are correct.

  2. 1 and 2 are correct and 3, 4 and 5 are wrong.

  3. 2 and 4 are correct and 1, 3 and 5 are wrong.

  4. 1 and 5 are correct and 2, 3 and 4 are wrong.

  5. 2, 3 and 4 are correct and 1 and 5 are wrong.
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Albumin protein in plasma is responsible for maintaining osmotic balance. Plasma constitutes about 55% of the human blood and blood cells constitute 45% of the human blood. Minerals like sodium, potassium, calcium regulate normal blood pressure. Blood clotting factors are present in blood. Serum is the plasma from which clotting factors have been removed. 

Thus, the correct answer is option E. 

Multiple choice biology simple nutrients into cells blood and its components components of blood composition of blood

Which of the above statements is correct and which are false?
(1) Plasma constitutes 45% of the human blood.
(2) Albumin is a plasma protein, which helps in osmotic balance.
(3) Factors responsible for the blood clotting process are present in the blood.
(4) Plasma without clotting factors is called serum.
(5) Minerals are not generally found in blood.

  1. Only 5 is wrong and all others 1 to 4 are correct.

  2. 1 and 2 are correct and 3, 4 and 5 are wrong.

  3. 2 and 4 are correct and 1, 3 and 5 are wrong.

  4. 1 and 5 are correct and 2, 3 and 4 are wrong.

  5. 2, 3 and 4 are correct and 1 and 5 are wrong.
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Plasma is the pale yellow colored component of blood that makes up for 55% of the bloods total volume. The plasma though it is made up of 95% water it contains proteins such as albumins. The anticoagulant are present in the blood itself.  Blood serum is blood plasma without the coagulant factors.

Multiple choice bio-chemistry proteins denaturation of protein proteins and amino acids proteins and enzymes

Primary structure of a protein is?

  1. sequence in which $\alpha-$ amino acids are linked to one another

  2. sequence in which amino acids of one polypeptide chain are joined to other chains

  3. the folding patterns of polypeptide chains

  4. the pattern in which the polypeptide chain are arranged
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The primary structure of a protein refers to the sequence of amino acids in the polypeptide chain. The primary structure is held together by peptide bonds that are made during the process of protein biosynthesis.
Multiple choice bio-chemistry proteins denaturation of protein proteins and amino acids proteins and enzymes

Most common types of secondary structures of proteins are?

  1. $\alpha-$ helix and $\beta-$ helix structures
  2. $\alpha-$ helix and $\beta-$ pleated structures

  3. right and left hand twisted structures

  4. globular and fibrous structures
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
The most common types of secondary structures are the $\alpha$ helix and the $\beta$ pleated sheet. Both structures are held in shape by hydrogen bonds, which form between the carbonyl O of one amino acid and the amino H of another.
Multiple choice bio-chemistry proteins denaturation of protein proteins and amino acids proteins and enzymes

Proteins are found to have two different types of secondary structures vix. $\alpha-$ helix and $\beta-$ pleated sheet structure, $\alpha-$ helix structure of a protein is stabilised by:

  1. peptide bonds

  2. van der Waals forces

  3. hydrogen bonds

  4. dipole-dipole interactions
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Answer:- (C) hydrogen bonds

Two major factors stabilize the $\alpha$-helix structure are intrachain H-bonding and minimization of steric interference between side chains.

Multiple choice bio-chemistry proteins denaturation of protein proteins and amino acids proteins and enzymes

Cheese is a

  1. Glubular protein

  2. Conjugated protein

  3. Denatured protein

  4. Derived protein
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Cheese is a denatured protein. When producing (hard or semi-hard) cheese, the cheese yield can be increased by subjecting part of the cheese milk to a high temperature heat treatment. Thermal denaturation of whey proteins changes the protein structure so that part of the whey remains in the curd during the cheese-making process. 

Multiple choice bio-chemistry proteins denaturation of protein proteins and amino acids proteins and enzymes

Denaturation of proteins can be carried out by

  1. heat

  2. mineral acids

  3. bases

  4. all of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Denaturation of proteins can be carried out by heat, mineral acids or bases. Denaturation is a process in which proteins lose their quaternary, tertiary and secondary structure which is present in their native state by application of some external stress or compound, such as a strong acid or base, a concentrated inorganic salt, an organic solvent, radiation or heat. If proteins in a living cell are denatured, it results in disruption of cell activity and possibly cell death. Denatured proteins can exhibit a wide range of characteristics from loss of solubility to communal aggregation.