The salivary gland chromosomes in the dipteran larva, are useful in gene mapping because:
1. | They have endoreduplication chromosomes |
2. | These are fused |
3. | These are easy to stain |
4. | These are much longer in size |
If Mendel might have studied 7 pairs of characters in a plant with 12 chromosomes instead of 14 then:
1. | He could not discover an independent assortment |
2. | He might have discovered linkage |
3. | He might have discovered crossing over |
4. | He might have not observed dominance |
Mental retardation in man occurs due to:
1. Loss of one X chromosome
2. Addition of one X chromosome
3. Slight growth in Y
4. Overgrowth in Y
A male human is heterozygous for autosomal genes A and B and is also hemizygous for hemophilic gene h. What proportion of his sperm will be ABH?
1. | 1/32 | 2. | 1/16 |
3. | 1/4 | 4. | 1/8 |
A self-fertilizing trihybrid plant forms:
1. | 4 different gametes and 16 different zygotes |
2. | 8 different gametes and 16 different zygotes |
3. | 8 different gametes and 32 different zygotes |
4. | 8 different gametes and 64 different zygotes |
A gene is said to be dominant if:
1. | It expresses its effect only in the homozygous stage |
2. | It expresses only in heterozygous condition |
3. | It expresses both in homozygous and heterozygous conditions |
4. | It is never expressed in any condition |
Study the pedigree chart of a certain family given below and select the correct conclusion which can be drawn for the character:
1. | The parents could not have had a normal daughter for this character |
2. | The trait under study could not be colourblindness |
3. | The male parent is homozygous dominant |
4. | The female parent is heterozygous |
Represented below is the inheritance pattern of a certain type of traits in humans. Which one of the following conditions could be an example of this pattern?
1. | Sickle cell anemia | 2. | Haemophilia | |
3. | Thalassemia | 4. | Phenylketonuria |
Given below [A – E] are suggested causes for the genetic diseases. Select the cause as your answer for the given disease.
A. | A single nucleotide mutation results in a polar amino acid being substituted by a non-polar amino acid in the polypeptide. |
B. | Autosomal recessive inborn error of metabolism where mutation renders a key enzyme involved in amino acid metabolism non-functional. |
C. | X-linked recessive condition is more common in males than in females. |
D. | Caused by a primary autosomal non-disjunction event. |
E. | Caused by a non-disjunction event in sex chromosomes in either of the sexes. |
Red-green colour blindness:
1. | A | 2. | B |
3. | C | 4. | D |
Given below [A – E] are suggested causes for the genetic diseases. Select the cause as your answer for the given disease.
A. | A single nucleotide mutation results in a polar amino acid being substituted by a non-polar amino acid in the polypeptide. |
B. | Autosomal recessive inborn error of metabolism where mutation renders a key enzyme involved in amino acid metabolism non-functional. |
C. | X-linked recessive condition is more common in males than in females. |
D. | Caused by a primary autosomal non-disjunction event. |
E. | Caused by a non-disjunction event in sex chromosomes in either of the sexes. |
Sickle cell anaemia:
1. | A | 2. | B |
3. | C | 4. | D |