21.

Dark grown Arabidopsis seedlings show ‘triple response’ when exposed to ethylene hormone. Which one of the following options is characteristic of ‘triple response’? 

• Reduced shoot elongation, increased shoot thickness and tightening of apical hook

• Reduced shoot elongation, reduced shoot thickness and loosening of apical hook

• Increased shoot elongation, increased shoot thickness and loosening of apical hook

• Increased shoot elongation, reduced shoot thickness and tightening of apical hook.

Brassinosteroids are a group of steroid hormones that function in a variety of cellular and developmental contexts in plants. Which one of the following acts as an inhibitor of the brassinosteroid receptor?

•  BRI 1

• BKI 1

• BAK 1

•  BSK 1

Which one of the following metabolites moves from mitochondria to peroxisome during the operation of the C₂ oxidative photosynthetic cycle?

• Glycerate

• Glycolate 

• Glycine

• Serine

Sympathetic post-ganglionic neurons that are cholinergic, innervate ?

• Sweat glands

• parotid glands

• hair follicle

• Pancrease

Melanopsin is found in which cell of the retina?

• Cones

• Rods

• Ganglion cells

• Bipolar cell

Prestin, a membrane protein, is found in which one of the following cells of the organ of Corti? 

• Inner hair cells

• Inner phalangeal cells

• Outer hair cells

• Outer phalangeal cells

Two individuals A and B, each of 75 kg body weight, have similar volume of body water. Both of them had high salt snack. However, individual A also had a glass of alcoholic drink. Based on this information, which one of the following statements is true?

• A will have lower circulating level of antidiuretic hormone (ADH) than B 

• B will have lower circulating level of ADH than A

• The level of ADH will not change in these two individuals 

• The reabsorption of water in kidney will be more in A than B

An intron was cloned within a transposable element. Absence of the intron following transposition of the element, will indicate that it 

• follows conservative mode of transposition

• follows replicative mode of transposition

•  is a retrotransposon 

• is an insertion element 

 In an organism, allele for red eye colour is dominant over the allele for white eye colour. A cross is made between a white eyed male and a red eyed female. In the progeny, all males are red eyed while the females are white eyed. The reciprocal cross leads to all red eyed progeny. Based on the above information which one of the following conclusions is correct?

• This is a sex-limited trait, and the male is the homomorphic sex 

• This is a sex-linked trait, with male being the homomorphic sex

• This is a sex-linked trait, with female being the homomorphic sex

• This is a case of autosomal inheritance, with incomplete penetrance

In a sample from a population there were 65 individuals with BB genotype, 30 individuals with Bb genotype and 15 individuals with bb genotype. The frequency of the ‘b’ allele is

• 0.59

• 0.27

• 0.41

• 0.73