Question

'Different species use different strategies to determine sex of a new born individual. It can be environmental cues or genetically determined'. Explain the statement by giving example for each strategy.

Answer 1

'Different species use different strategies to determine sex of a new born individual. It can be environmental cues or genetically determined. The following examples will validate this statement.

Environmental Cue:-

(a) In some animals, the temperature at which fertilized eggs are kept determines whether the developing animal in the egg is male or female. Ex- lizard

(b) In some animals like the snail, an individual can change sex.under different stress and environmental conditions.

Genetically – In humans a child who inherits an x chromosome from her father will be a girl and one who inherits a y chromosome from the father will be a boy, because in the case of humans the males determine the gender of the child because human males are heterogametic (XY) and human females are homogametic (XX).