One of the genes present exclusively on the X-chromosome in humans is concerned with
1. Baldness
2. Red-green color blindness
3. Facial hair/moustaches in males
4. Night blindness

Self fertilising trihybrid plants form
1.Eight different gametes and 64 different zygotes
2. Four different gametes and sixteen different zygotes
3. Eight different gametes and sixteen different zygotes
4. Eight different gametes and thirty two different zygotes

A mutation at a gene locus changes a character due to change in
1. DNA replication
2. Protein synthesis pattern
3. RNA transcription pattern
4. Protein structure

A normal woman whose father was colour blind is married to normal visioned man. Their sons would be
1. 75% colour blind
2. 50% colour blind
3. 100% colour blind
4. All normal.

In a plant, red fruit (R) is dominant over yellow fruit (r), and tallness (T) is dominant over shortness (t). A plant with RRTt genotype is crossed with a plant of rrtt genotype. The progeny is:
1. All red fruit, tall 25%
2. All red fruit, tall 50%
3. All red fruit and tall 75%
4. All red fruit and tall.

For finding the different types of gametes produced by genotype AaBb, it should be crossed with genotype
1. AABB
2. aabb
3. AaBb
4. aaBB.

A normal couple has seven children (2 daughters and 5 sons). Three of the sons suffer from a hereditary disorder but none of the daughters is affected. Which is the inheritance type
1. Sex-limited recessive
2. Autosomal dominant
3. Sex-linked dominant
4. Sex-linked recessive.

A woman with 47 chromosomes due to presence of additional 21 chromosomes is characterised by
1. Super female
2. Turner’s syndrome
3. Down’s syndrome
4. Triploidy

Which one is not a hereditary disease
1. Cystic fibrosis
2. Cretinism
3. Thalassaemia
4. Haemophilia

A woman with normal vision but with colorblind father marries a colorblind man. The fourth child of the couple is a boy. This boy
1. May or may not be colorblind
2. Must be colorblind
3. Must have normal vision
4. Will be partially colorblind due to being heterozygous