Recessive Traits

Q.

This pedigree shows the inheritance of colour blindness or sex-linked trait. Is this trait dominant or recessive? Is the mother of the colourblind girl in the F3 generation colourblind, a carrier or a person with normal colour vision? Explain. [4 MARKS]

Q.

List any three features of garden pea with their dominant and recessive traits.

Q.

The gene for red hair is recessive to the gene for black hair. What will be the hair colour of a person if he inherits a gene for red hair from his mother and a gene for black hair from his father?

Q.

What Is the Basis of Heredity?

Q.

A Mendelian experiment consisted of breeding pea plants bearing violet flowers with pea plants bearing white flowers. What will be the result in F1 progeny

Q.

Assuming black fur is dominant over brown fur in rabbit, what would the genotype of rabbits that are heterozygous for coat colour?

1. BB

2. bb

3. Bb

4. B

Q.

The type of gene, which in the presence of a contrasting allele is not expressed.

Q.

Are blue eyes recessive?

Q. Recessive gene can express itself only in________.

1. homozygous condition
2. heterozygous condition
3. homo-hetrozygous condition
4. ominizygous

Q.

What Type Of Variation Is Eye Colour?

Q.

The suppressed allele of a gene.

Q.

Question 34
Give the pair of contrasting traits of the following characters in pea plant and mention which is dominant and recessive.
(i) yellow seed (ii) round seed (iii) green seed (iv) wrinkled seed.

Q.

Dominant trait is one that

1. decides fate of organism in a population

2. is expressed in first filial generation

3. appears in the proportion of $\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$4$}\right.$in second filial generation.

4. qualifies an organism to be the primary consumer.

Q. Identify the blood group allele(s) which do/does not express itself/themselves in heterozygous condition but express, when present in homozygous condition.

1. $I^A$ and $I^B$
2. $I^B$ and $I^O$
3. $I^O$ only
4. $I^A$ only

Q.

What is polygenic inheritance?

Q. The phenotypic and genotypic ratio in incomplete dominance is

1. 1:2:1
2. 9:3:3:1
3. 3:1
4. 9:7

Q.

…………………….will express the recessive character or trait.

1. F1 generation

2. F2 generation

3. Both A and B

4. None of the above

Q. Out of 600 pea seeds, 450 seeds produced were yellow in F₂ generation. If yellow (Y) seed is a dominant trait and green (y) seed is a recessive trait, then the correct genotype of parents were

मटर के 600 बीजों में से F₂ पीढ़ी में उत्पन्न हुए 450 बीज पीले बीज थे। यदि पीला (Y) बीज एक प्रभावी लक्षण है तथा हरा (y) बीज एक अप्रभावी लक्षण है तो जनकों का सही जीनप्ररूप (जीनोटाइप) था

1. YY and YY
   
   YY तथा YY
2. yy and yy
   
   yy तथा yy
3. YY and yy
   
   YY तथा yy
4. Yy and YY
   
   Yy तथा YY

Q. Which are some of the dominant and recessive traits in human beings?

Q. how do mendels experiments shoe that a trait could be dominant or recessive?

Q. Out of 800 pea seeds, 600 seeds produced were yellow in F₂ generation. If yellow (Y) seed is a dominant trait and green (y) seed is a recessive trait, then the correct genotype of parents were

मटर के 800 बीजों में से, F₂ पीढ़ी में उत्पन्न हुए 600 बीज पीले रंग के थे। यदि पीला (Y) बीज एक प्रभावी लक्षण है तथा हरा (y) बीज एक अप्रभावी लक्षण है तो जनकों के सही जीनप्ररूप (जीनोटाइप) थे

1. YY and YY
   
   YY तथा YY
2. yy and yy
   
   yy तथा yy
3. YY and yy
   
   YY तथा yy
4. Yy and YY
   
   Yy तथा YY

Q. List 2 difference between dominant traits and recessive traits. [2 Marks]

Q.

The allele that fails to express _______________________________.

Q. How many $F_2$ plants having two dominant alleles typically dihybrid cross ?

1. 6/16
2. 10/16
3. 9/16
4. 1/16

Q.

What would have Mendel got if he would have self pollinated a tall F₂ plant?

Q. Note down the allele pairs studied by Mendel. Mention which allele is dominant.

Q.

In a pair of contrasting traits, expressing traits and not expressing traits in the progeny are called as _____ and _____ respectively.

1. recessive ; genotypic

2. phenotypic ; genotypic

3. recessive ; dominant

4. dominant ; recessive

Q. A trait may be inherited, but may not be expressed. Justify this statement with the help of a suitable example.

Q. Identify the recessive traits in a pea plant.

1. White flower
2. Purple flower
3. Yellow seed
4. Green seed
5. Wrinkled seed
6. Round seed
7. Green pod
8. Yellow pod
9. Tall plant
10. Dwarf plant

Q.

In 4 ‘o’clock plants, the crossing of pure-breed red and white flowered parental stocks produced pink flowered plants. This type of genotypic expression is called ___.

1. Dominance

2. Gene polymorphism

3. Incomplete dominance

4. Codominance