Biology

Molecular Biology and Genetics

985 Questions

Molecular biology and genetics explore the structure and function of DNA, RNA, genetic mutations, and heredity. Understanding these building blocks of life is essential for most biology examinations. Review these practice questions to test your molecular genetics knowledge.

DNA structure and basesGenetic mutationsNucleic acids compositionDNA sequencing and replication

Molecular Biology and Genetics Questions

Multiple choice

____________ are examples of protein-protein interaction databases.

  1. BioGRID and Reactome

  2. STRING and SignaLink 2.0

  3. SignaLink 2.0 and Reactome

  4. BioGRID and STRING

  5. Reactome and STRING
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The Biological General Repository for Interaction Datasets (BioGRID) is a curated biological database of protein-protein and genetic interactions. STRING is a database of known and predicted protein interactions.

Multiple choice

Which of the following pairs represents primary databases?

  1. SWISS-PROT and PROSITE

  2. SWISS-PROT and Genbank

  3. PROSITE and Genbank

  4. PROSITE and Pfam

  5. Genbank and Pfam
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Databases consisting of data derived experimentally, such as nucleotide sequences and three-dimensional structures, are known as primary databases. Examples: SWISS-PROT and Genbank

Multiple choice

Identify the incorrect matching.

  1. PROSITE: Database of protein families and domains

  2. Reactome: Navigable map of human biological pathways

  3. BRENDA: Comprehensive enzyme information system

  4. PhenomicDB: Database linking human mutations with phenotype

  5. PRINTS: A compendium of protein fingerprints
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

PhenomicDB is a multi-organism phenotype-genotype database including humans, mice, fruit flies, C.elegans and other model organisms.

Multiple choice

A purine is a colourless crystalline solid which can be prepared from uric acid. Which of the following is a purine derivative?

  1. Xanthine

  2. Hypoxanthine

  3. Xanthosine 5'-triphosphate

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

Hypoxanthine is a naturally occurring purine derivative. It is occasionally found as a constituent of nucleic acids where it is present in the anticodon of tRNA in the form of its nucleoside inosine. It has a tautomer known as 6-Hydroxypurine. Hypoxanthine is a necessary additive in certain cell, bacteria, and parasite cultures .

Multiple choice

Guanine is one of the five main nucleobases found in the nucleic acids i.e., DNA and RNA. Which of the following is a guanine analogue antiviral drug?

  1. Enfuvirtide

  2. Entecavir

  3. Entry inhibitor

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

Famciclovir is a guanine analogue antiviral drug used for the treatment of various herpesvirus infections, most commonly for herpes zoster (shingles). It is a prodrug form of penciclovir with improved oral bioavailability.

Multiple choice

Which among the following statements does not characterise apoptosis?

  1. A cell initiates intracellular apoptotic signaling in response to a stress.

  2. The regulatory proteins initiate the apoptosis pathway.

  3. Targeting mitochondria functionality is one of the methods of apoptosis.

  4. Apoptosis produces cell fragments to be engulfed by phagocytic cells.

  5. Nitrous oxide has been implicated in initiating and inhibiting apoptosis.
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Nitric oxide has been implicated in initiating and inhibiting apoptosis through its possible action as a signal molecule of subsequent pathways that activates apoptosis

Multiple choice

Which of the following contains genetic instructions?

  1. Deoxyribonucleic acid

  2. Dexamethasone

  3. Dextran

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

Deoxyribonucleic acid or DNA, is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms (with the exception of RNA viruses). The main role of DNA molecules is the long-term storage of information.

Multiple choice

-------------------- is a base found in DNA and RNA.

  1. Cysteamine

  2. Cysteine

  3. Cystine

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

Cytosine (C) is one of the four main bases found in DNA and RNA, along with adenine, guanine, and thymine (uracil in RNA). It is a pyrimidine derivative, with a heterocyclic aromatic ring and two substituents attached (an amine group at position 4 and a keto group at position 2).

Multiple choice

In isopycnic centrifugation, the molecules are separated on the basis of density. The compound used in isopycnic centrifugation of various types of DNA is

  1. Caesium carbonate

  2. Caesium chromate

  3. Caesium chloride

  4. Caesium fluoride
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Its crystal structure forms a major structural type where each caesium ion is coordinated by 8 chlorine ions.Caesium chloride is widely used in isopycnic centrifugation for separating various types of DNA. It is a reagent in analytica  l chemistry, where it is used to identify ions by the colour and morphology of the precipitate.

Multiple choice

Which is the peculiar feature of chemical synthesis of oligonucleotides?

  1. DNA polymerase is involved in chemical synthesis.

  2. Template is required for oligonucleotide synthesis.

  3. Synthesis of oligonucleotide in 5'-3' direction.

  4. Synthesis of oligonucleotides in 3'-5' direction.

  5. None of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Chemical synthesis of oligonucleotides occur in 3'-5' direction.