Which of the following is a recessive trait for a character choosen by Mendel in garden pea?
1. Violet flower color
2. Yellow pod color
3. Axial flower position
4. Tall stem height
Indentify the incorrect statement:
1. Tall plant produce gametes by meiosis and the dwarf plants by mitosis.
2. Only one allele is transmitted to a gamete.
3. The segregation of alleles is a random process.
4. Gametes will always be pure for the trait.
In the case of co-dominance, the F1 generation resembles:
(1) Dominant parent
(2) Recessive parent
(3) Both the parents
(4) None of the parents
In case of starch synthesis in pea seeds [controlled by B gene], BB homozygotes produce large and round starch grains; bb homozygotes produce smaller and wrinkled starch grains and Heterozygotes produce round seeds of intermediate size. What can be inferred from this observation?
(1) The gene B mutates at a faster rate.
(2) The gene B is easily influenced by the environment
(3) Dominance is not an autonomous feature of a gene or the product that it has information for
(4) Some genes do not follow the law of segregation.
When Morgan hybridised yellow-bodied, white-eyed females to brown-bodied, red-eyed males and intercrossed their F1 progeny, the F2 ratio deviated very significantly from the 9:3:3:1 ratio. this can be attributed to the fact that:
(1) The genes are located on X and Y chromosomes
(2) Fruit fly has abnormal chromosomes
(3) The genes are located on the X chromosome
(4) The genes exhibit incomplete dominance
What is incorrect for Hemophilia?
1. In this disease, a single protein that is a part of the cascade of proteins involved in the clotting of blood is affected.
2. In an affected indlvidual a simple cut will result in non-stop bleeding.
3. The heterozygous female (carrier) for haemophilia may transmit the disease to sons.
4. The possibility of a female becoming a haemophilic is extremely rare because mother of such a female has to be hemophilic and the father should be a carrier.
Sickle cell anaemia results from.
1. A chromosomal aberration
2. Non disjunction of autosome
3. A point mutation
4. Blood transfusion reaction
Which of the following is not a feature of Down's Syndrome?
1. It is caused by a non-disjunction in an autosome
2. The affected individual has trisomy of chromosome 21
3. The aflected individual has a characteristic simian palmar crease
4. The mental development of affected individual is normal
Match each item in Column I with one item in Column II and chose your answer from the codes given below:
Column I Disorder |
Column II Feature |
I. Phenylketonuria II. Sickle Cell anemia III. Down's Syndrome IV. Turner's Syndrome |
(i) Rudimentary ovaries (ii) Gynecomastia (iii) Trisomy 21 (iv) Lack of enzyme PAH (v) Lack of tyrosinase (vi) Mutation GAG to GUG (vii) Mutation GUG to GAG |
1. I - v; II - vii; III - iii; IV - i
2. I - iv; II - vi; III - iii; IV - i
3. I - v; II - vi; III - iii; IV - ii
4. I - v; II - vi; III - iii; IV - i
In a monohybrid cross F1 progeny resemble neither of the parents. What would be true in this case?
1. The parental traits would not appear in any of the F2 -progenies
2. The F2 phenotypic ratio will be different from the F2 genotypic ratio
3. It could be a case of incomplete dominance
4. The F2 phenotypic ratio will be similar to any Mendelian monohybrid cross