Tag: zoology

Questions Related to zoology

From the given data characteristics identify the correct pre - historic man:

(i) They were about 1.8m tall with well built body.

(ii) Broad and arched forehead and also well developed chin.

(iii) They could walk and run faster.

(iv) They made excellent tools and cave paintings.

zoology evolution evidences for evolution - taxonomy, molecular biology and cytology evidences of evolution evidences of biological evolution

  1. Cro-Magnon man.

  2. Tuang baby and Lucy.

  3. Pithecanthropus erectus.

  4. Tool maker.

Show answer
Correct Option: A

Teacher asks the student to give the best example to explain pleiotropy. The correct answer is

pleiotropy genetics zoology

  1. Flower colour in snapdragon

  2. Seed coat colour of garden pea

  3. ABO blood group system of human

  4. Phenylketonuria

Show answer
Correct Option: D
Explanation:

Pleiotropy occurs when one gene will code and control the phenotype or expression of several different and unrelated traits. Phenylketonuria is an autosomal recessive disorder controlled by a mutant gene present on the 12th chromosome. This mutant gene fails to code for the enzyme phenylalanine hydroxylase required for normal metabolism of amino acid phenylalanine to tyrosine. Due to this, there is an accumulation of phenylalanine in body fluids such as blood, sweat, CSF. An abnormal breakdown product phenyl ketone is found in urine A higher level of phenylalanine and pheylketone cause severe brain damage leading to mental retardation. Thus phenylketonuria is the best example to explain pleiotropy.

So, the correct answer is 'Phenylketonuria'

A pleiotropic in Drosophila is that of

pleiotropy genetics zoology

  1. Red-white eye

  2. Bar eye

  3. Vestigial gene

  4. Forked bristles.

Show answer
Correct Option: C

A $15: 1F _2 $ ratio of a cross between a wheat variety with red kernels (homozygous for two dominant genes) and another with white kernels shows 

pleiotropy genetics zoology

  1. Polygenic inheritance

  2. That the two genes are complementary

  3. Single factor inheritance

  4. That it is a tes cross

Show answer
Correct Option: A
Explanation:

E.Nilsson – Ehle crossed red kernelled variety with white kernelled variety of wheat. The grains of F1 were self crossed among themselves, five different phenotypic classes appeared in F2 showing the ratio of 1:6:15:20:15:6:1.

These scientist found that the kernel colour in wheat is determined by two pairs of genes A and B. It is called polygenic inheritance.

So, the correct option is ‘polygenic inheritance’.

A pleiotropic gene in humans is

pleiotropy genetics zoology

  1. Marfan's syndrome

  2. Colour blindness

  3. Eye colour

  4. Height

Show answer
Correct Option: A
Explanation:

Mutations in the human gene for fibrillin-1 (FBN1) in the Marfan syndrome and related disorders. Mutations in FBN1 produce Marfan syndrome, a pleiotropic autosomal dominant connective tissue disorder with prominent manifestations in the skeleton, eye and cardiovascular system.

So, the correct information is 'Marfan's syndrome.'

Occasionally, a single gene may express more than one effect. The phenomenon is called

pleiotropy genetics zoology

  1. multiple allelism

  2. mosaicism

  3. pleiotropy

  4. polygeny.

Show answer
Correct Option: C
Explanation:

When there are three or more alternative forms of a gene, it is called multiple allelism. Polygeny suggests that humans evolved from several different ancestors. When a single gene has more than one effects, it is called pleiotropy.

So, option C is the correct answer.

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

pleiotropy genetics zoology

  1. Pleiotropy

  2. Incomplete dominance

  3. Codominance

  4. Complete dominance

Show answer
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?

pleiotropy genetics zoology

  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

Show answer
Correct Option: A

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

pleiotropy genetics zoology

  1. Epistasis

  2. Dominance

  3. Segregation

  4. Pleiotropy

  5. Independent assortment

Show answer
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

pleiotropy genetics zoology

  1. Polygene

  2. Pleiotropic gene

  3. Multifactor gene

  4. Multiple gene.

Show answer
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’.