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 zoology molecular basis of inheritance genome projects human genome project human genome project and dna fingerprinting

Lily has .......... more DNA than human genome.

  1. 10 times

  2. 4 times

  3. 20 times

  4. 18 times
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The main aim of the Human Genome Project was to determine the sequence of 3.2 billion base pairs of Human Genome and to identify their functions.

It was found that Human Genome contains around 30,000 jeans and 99.9% of nucleotide bases and all human beings are same.
The amount of genes present in Lily is 18 times more than the Human Genome.

So, the correct option is '18times'.

Multiple choice zoology molecular basis of inheritance genome projects human genome project human genome project and dna fingerprinting

Human genome contains base pairs

  1. 2.5 million

  2. 25 million

  3. 27.2 million

  4. 3.2 billion
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

There are four bases adenine (A), thymine (T), guanine (G) and cytosine (C) present in humans. Bases on opposite strands pair specifically as an A always pairs with a T, and a C always with a G. The human genome contains approximately 3.2 billion of these base pairs, which reside in the 23 pairs of chromosomes within the nucleus of all our cells.

So, the correct option is '3.2 billion'.

Multiple choice zoology molecular basis of inheritance genome projects human genome project human genome project and dna fingerprinting

A ribotide is made of

  1. Adenine + Deoxyribose + Phosphate

  2. Uracil + Ribose + Phosphate

  3. Thymine + Ribose + Phosphate

  4. Uracil + Deoxyribose + Phosphate
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A ribotide (ribonucleotide) consists of a nitrogenous base (like Uracil in RNA), a ribose sugar, and a phosphate group. Deoxyribose is found in DNA, not RNA.

Multiple choice zoology molecular basis of inheritance genome projects human genome project human genome project and dna fingerprinting

Which ones are degenerate codons ?

  1. UAA, UAG and UGA

  2. GUA, GUG, GCA, GCG and GAA

  3. UUC, UUG, CCU, CAA and CUA

  4. UUA, UUG, CUU, CUC, CUA and CUG

  5. AAC, AAG, GAC and CGG
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Degeneracy means that multiple codons can code for the same amino acid. The set UUA, UUG, CUU, CUC, CUA, and CUG all code for the amino acid Leucine.

Multiple choice zoology molecular basis of inheritance genome projects human genome project human genome project and dna fingerprinting

As per latest information human genome has

  1. $3,00,000$ genes
  2. $20,000$ genes
  3. $3,000$ genes
  4. $300$ genes
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
There are an estimated 19,000-20,000 human protein-coding genes. The estimate of the number of human genes has been repeatedly revised down from initial predictions of 100,000 or more as genome sequence quality and gene finding methods have improved and could continue to drop further.
So, the correct answer is '20,000 genes'.
Multiple choice zoology molecular basis of inheritance genome projects human genome project human genome project and dna fingerprinting

The human genome contains (a) billion nucleotide bases. The average gene consists of (b) bases. Which option is correct for a & b?

  1. $a = 3, b = 3000$
  2. $a = 5, b = 3000$
  3. $a = 3, b = 2000$
  4. $a = 4, b = 3000$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The human genome contains approximately 3 billion base pairs, and the average gene size is estimated to be around 3000 base pairs.

Multiple choice botany caskets of life the cell structure multicellular organisms number and shape of cells

Which of the following is an exception with either RNA or DNA in the cell as genetic material ? 

  1. Algae

  2. Fungi

  3. Bacteria

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

Viruses are an exception to cell theory as it is an acellular organism that is living inside the host and nonliving outside the host. In viruses, only one nucleic acid (DNA or RNA) is present. Thus, a virus can be either a DNA virus or an RNA virus. Viruses infecting animals usually have DNA as genetic material. Viruses infecting plants usually have RNA as genetic material. All eukaryotic cells have both DNA and RNA in their cells.

Multiple choice evs nutritious food minerals and vitamins nutrition and diet role of various nutrients

Cataloguing and analysing every protein in the human body

  1. Biochip

  2. Proteomics

  3. Both

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

Proteomics is the cataloging and analyzing every protein in the human body most proteins differ in their folding manner, which is governed by genes. Biotechnology helps us in discovering protein structure.

Multiple choice bio-chemistry nucleic acids central dogma transcription and gene expression molecular biology

Which one of the following does not follow the central dogma of molecular biology?

  1. Chlamydomonas

  2. HIV

  3. Pea

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

The central dogma of molecular biology says DNA, i.e., deoxyribonucleic acid is replicated first to form a copy of DNA. This process is known as DNA replication and is catalyzed by an enzyme called as DNA polymerase (DNA dependent DNA polymerase). This replicated DNA is then transcribed to form an mRNA (messenger RNA molecule). This process is referred as transcription and this is carried out by an enzyme called as RNA polymerase (DNA dependent RNA polymerase), finally the mRNA is translated into a protein.This process is carried out by ribosomes where amino acids are incorporated. This process is known as translation. Francis Crick proposed this concept of central dogma in molecular biology which states that genetic information flows from DNA->DNA->protein. In some viruses, the flow of information is in reverse direction, i.e., from RNA to DNA. This process is known as reverse central dogma or reverse transcription. It takes place in viruses, acellular organisms where RNA replicates via a DNA intermediate. A complimentary DNA molecule is formed from genomic RNA with the help of an enzyme called reverse transcriptase ( RNA dependent DNA polymerase). Eg : HIV which is a retrovirus.