Principles Of Inheritance And Variation - Botany - Biology Previous Year Questions

Observe the given figure of Morgan's experiment for yellow body and white eyed female Drosophila crossed with brown body and red eyed male Drosophila. What will be the percentage of parental type in $F_2$ generation?

Chromosomal basis of inheritance suggested by Sutton and Boveri is based on ________

Non-disjunction of X-chromosomes during meiosis in the formation of ovum leads to _________ syndrome.

A type of chromosomal aberration, in which there is no loss or gain of gene complement of the chromosome is $\qquad$ .

Choose the correct statement(s) with respect to Down's syndrome

i. Down's syndrome results from non-disjunction of $21^{\text {st }}$ chromosome during gamete formation.

ii. Down's syndrome is a sex chromosomal disorder observed in immature mothers who are below the age of 18 .

iii. These patients have mild mental retardation, poor skeletal development, flat hands, stubby fingers and palms are broader.

iv. The have 44 A with XO type of karyotype.

v. The risk of giving birth to a Down Syndrome child is more in mothers who are over 45 years of age.

Test cross is used to confirm $\qquad$ .

Which one of the following is an EXCEPTION to the generalization made by Mendel on the basis of his experiments on garden pea plant?

Which of the following statements are correct?

i. $X$ chromosome has large amount of euchromatin.

ii. heterochromatin is genetically inert.

iii. Both X and Y chromosomes are homologous.

iv. Crossing over does not take place in sex chromosomes in female.

Choose the correct option.

Given below are two statements:

Statement I - Back cross is the crossing of $F_1$ hybrid with one of the two parents from which they were derived.

Statement II - Test cross involves the crossing of $F_1$ - hybrid with its homozygous recessive parent.

In light of above statements, choose the correct answer from the option given below.

Monohybrid crosses are useful in demonstrating which of the following laws of inheritance suggested by Mendel?

What is the probability of producing a colourblind son if a colourblind male marries a normal visioned female?

Which one of the following is NOT a sex linked disorder?

Red (RR) flowered plant of Mirabilis is crossed with white (rr) flowered plant. All the offsprings in $\mathrm{F}_1$ generation are pink ( Rr ). This is an indication that the ' R ' gene is __________

Which one of the following is an important symptom of haemophilia?

A large population is showing random mating and not undergoing any evolutionary change. If frequency of allele A is 0.6 , then find out the percentage of homozygous recessive and heterozygous organisms respectively?

Non-disjunction of X - chromosome during meiosis leads to __________

Sexually reproduced offsprings tend to differ from their parents. This is known as __________

If you cross two heterozygous plants, how many of the all possible $F_1$ offsprings will also be heterozygous?

Which of the following statements are correct regarding chromosomal basis of sex determination?

i. The mechanism of sex determination in insect is XX - XO type.

ii. In honey-bee, haplo-diploid type of sex determination is observed.

iii. Human males have homomorphic sex chromosomes.

iv. Human females have heteromorphic sex chromosomes.

v. Chromosomal mechanism of sex determination in birds is ZW-ZZ type.