Tag: genetics

Questions Related to genetics

In garden pea, gene controlling starch synthesis related to all of the given phenomenon, except

  1. Pleiotropy

  2. Incomplete dominance

  3. Codominance

  4. Complete dominance


Correct Option: A
Explanation:

Pleiotropy occurs when one gene influences two or more unrelated phenotypic traits. So, pleitrophy cannot play a role in gene controlling starch synthesis.

Which of the following is not a pleiotropic gene?

  1. Starch branching enzyme coding gene

  2. Flower colour gene of Pisum sativum

  3. Leaf colour gene of snapdragon

  4. I gene of Blood group


Correct Option: A

When one gene is responsible for affecting more than one characteristics, the phenomenon is known as

  1. Epistasis

  2. Dominance

  3. Segregation

  4. Pleiotropy

  5. Independent assortment


Correct Option: D
Explanation:

Though Mendel through his experiments showcased inheritance of a trait as genetic, some traits results from the combined effect of more than one pair of genes. Contrary to this, a single gene may also be responsible for a variety of traits. This phenomenon is called pleiotropy.

A gene that shows its effect on more than one character is

  1. Polygene

  2. Pleiotropic gene

  3. Multifactor gene

  4. Multiple gene.


Correct Option: B
Explanation:

The ability of a gene to produce more than one phenotype in an organism is called Pleoitrophy and the genes are called Pleiotripic genes. It is not essential that the traits are equally influenced. Sometimes, the effect of the gene is more evident in case of one trait and less evident in case of another trait.

So, the correct option is ‘Pleiotropic gene’.

Same gene loci on two homologous chromosomes produce different phenotypes. They bear

  1. Homozygous alleles

  2. Heterozygous alleles

  3. Two different genes

  4. Pleiotropic genes


Correct Option: D
Explanation:

The ability of a gene to have multiple phenotypic effects is known as pleiotropy and the genes are called Pleiotropic genes. These genes influence the number of characters simultaneously. These genes are present on same loci on two homologous chromosomes and produce different phenotypes.

So, the correct option is ‘Pleiotropic genes’.

A pleiotropic gene is one which

  1. Affects one character

  2. Affects more than one character

  3. Supplements the effect of another gene

  4. Requires another gene for expression


Correct Option: B
Explanation:

The ability of a gene to produce more than one phenotype in an organism is called Pleoitrophy and the genes are called Pleiotripic genes. It is not essential that the traits are equally influenced. Sometimes, the effect of the gene is more evident in case of one trait and less evident in case of another trait.

So, the correct option is ‘Affects more than one character’.

Gene with multiple effects is

  1. Codominant

  2. Pleiotropic

  3. Epistatic

  4. Supplementary


Correct Option: B
Explanation:

A.Codominant – appearance of genotypes of both parents in the progeny is called codominance.

B.Pleiotropic - The ability of a gene to have a multiple phenotypic effects is known as pleiotrophy and the gene is called Pleiotropic gene.

C.Epistatic - A gene which masks the action of another gene is termed as epistasis. The gene is called epistatic gene and the gene whose effect is masked is termed as hypostatic gene.

D.Supplementary - genes which include two pairs of non-allelic genes. Both of them are involved in affecting the same character. Out of the non-allelic genes, one gene is dominant and can express by itself. Second gene is also dominant but expresses only when it is supported by the presence of the first gene.

So, the correct option is ‘Pleiotropic’.

Which is connected with multiple phenotypes?

  1. Epistasis

  2. Pleiotropy

  3. Polygenic inheritance

  4. Mutations


Correct Option: B
Explanation:

The ability of a gene to have a multiple phenotypic effects is known as pleiotrophy and the gene is called Pleiotropic gene.

So, the correct option is ‘Pleiotrophy’.

Multiple phenotype seen in ____________.

  1. Pleitropy

  2. Incomplete dominance

  3. Multiple allelism

  4. Polygenic inheritance


Correct Option: A
Explanation:
  • Pleiotropy occurs when one gene influences two or more seemingly unrelated phenotypic traits. 
  • Such a gene that exhibits multiple phenotypic expression is called a pleiotropic gene.
  • So, (A) is the correct answer.

The gene disorder phenyl ketonuria is an example for ___________.

  1. Polygenic inheritance

  2. Pleiotropy

  3. Multiple allelism

  4. Multiple factor.


Correct Option: B
Explanation:

Phenylketonuria is a recessive autosomal disorder related to phenylalanine metabolism. It is controlled by a single gene having  multiple phenotypes. So it is a pleiotrophy. This disorder is due to the absence of a liver enzyme phenylalanine hydroxylase. Due to the lack of this enzyme, phenylalanine follows another pathway and gets converted into phenyl pyruvic acid. This phenyl pyruvic acid upon accumulation in joints causes arthritis. If it hits the brain, it causes mental  retardation known as phenyl pyruvic idiocy.

So, the correct option is ‘Pleiotrophy’