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

Enzymes belong to what major class of biomolecules?

  1. lipids

  2. carbohydrates

  3. proteins

  4. nucleic acids
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Enzymes are specialized proteins that catalyze biological reactions. They are composed of amino acid chains folded into specific shapes.

Multiple choice

Which of these is a zymogen?

  1. Pepsin

  2. Trypsin

  3. Chymotrypsin

  4. Chymotrypsinogen
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A zymogen is an inactive precursor of an enzyme. Chymotrypsinogen is the inactive form that is converted into the active enzyme chymotrypsin.

Multiple choice evs food trends types of ecological pyramids the muscular system and digestive system in human beings introduction to human digestive system

How many of the enzymes given below in block belong to brush border enzymes?
Multase, Nucleosidase, Enterokinase, Amylopsin, Steapsin, Nucleases, Erepsin, Carboxypeptidase, Lactase, Aminopeptidase

  1. Six

  2. Seven

  3. Five

  4. Four
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The brush borders of the intestinal lining are the site of terminal carbohydrate digestions. The microvilli that constitute the brush border have enzymes for this final part of digestion anchored into their apical plasma membrane as integral membrane proteins. Maltase, lactase, erepsin, nucleosidase are the brush border enzymes.

So, the correct option is 'four'.

Multiple choice biology natural resources and agriculture manure manures and fertilisers role of organic manures in soil management

NPK denotes

  1. Nitrogen, protein and kinetic

  2. Nitrogen, protein and potassium

  3. Nitrogen, potassium and kinetic

  4. Nitrogen, phosphorus and potassium
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

NPK stands for Nitrogen, Phosphorous and Potassium as this abbreviation has three letters representing the names of the respective elements. It is used as a fertilizer.

Multiple choice zoology endocrine system and chemical co-ordination classification of hormones endocrine system and hormone hormones and metabolism

Identify the incorrect pair.

  1. Fatty acid- Insulin

  2. Glucose- Chitin

  3. Thymine- Nucleotide

  4. Amino acid- Hemoglobin

  5. Nitrogen- Uric acid
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Chitin is a polymer of N-acetyl glucosamine which in turn is a derivative of glucose. 

Thymine one of the purine (nitrogenous base) that makes deoxyribonucleotide units of DNA. 
Hemoglobin has four protein subunits, two alpha-globin and two beta-globin. Uric acid is a heterocyclic compound of CHON. 
Insulin is a protein hormone secreted by the pancreas.
So, the correct answer is option A.

Multiple choice zoology endocrine system and chemical co-ordination classification of hormones endocrine system and hormone hormones and metabolism

When all the peptide bonds of a protein have been broken down, the result would be

  1. Polypeptides

  2. Oligopeptides

  3. Peptides

  4. Amino acids
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Proteins are polymers of amino acids linked by peptide bonds. Complete hydrolysis (breaking all peptide bonds) results in the constituent amino acids.

Multiple choice zoology endocrine system and chemical co-ordination classification of hormones endocrine system and hormone hormones and metabolism

Biogenic amines are synthesized from

  1. Tryptophan

  2. Tyrosine

  3. Glutamic acid

  4. Phenylalanine
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Amines are the compounds that contain an amine group. They are formed as a result of deamination, a process in which amino group is removed from the amino acid. Some hormones like epinephrine and norepinephrine are amines. They are derived from amino acid tyrosine. 
So, the correct answer is 'Tyrosine'.
Multiple choice zoology endocrine system and chemical co-ordination classification of hormones endocrine system and hormone hormones and metabolism

Which among the following amino-acids is not essentially required for health?

  1. Cystenine

  2. Leucine

  3. Phenylalanine

  4. Tyrosin
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Cysteine is a nonessential amino acid (protein building block), meaning that cysteine can be made in the human body. Cysteine is one of the few amino acids that contains sulfur . Cysteine is a component of the antioxidant glutathione . The body also uses cysteine to produce taurine , another amino acid. So, the correct option is "A" (Cystenine).

Multiple choice

At what isoelectric point do caseins precipitate?

  1. pH 8.1

  2. pH 4.6

  3. pH 5.2

  4. pH 7.5
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The isoelectric point is the pH at which a protein has no net charge and becomes least soluble. For casein, this occurs at a pH of 4.6, which is why milk curdles when it becomes acidic.

Multiple choice zoology applications of biotechnology biotechnological regulations pcr asexual modes of reproduction

Maize hybrids have been developed for higher amount of

  1. Lysine

  2. Leucine

  3. Methionine

  4. Cysteine
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  • Maize hybrids with higher lysine content were developed to improve the protein in corn.
  • This hybrid maize provides substantially higher levels of two essential amino acids - Lysine and tryptophan.
  • So the correct answer is 'Lysine'