Question

When the dominant male of the blue-head wrasse is killed, the female will replace his role after she becomes a he (sequential hermaphrodism). What type of mechanism of sex determination is illustrated in this example?

a) Genetic sex determination
b) Environmental sex determination
c) Hormonal sex determination
d) Sequential hermaphroditism
e) Simultaneous hermaphroditism

Answer 1

The sex determination mechanism displayed by the blue-head wrasse's ability for females to change into males after the dominant male is removed is called sequential hermaphroditism.

Step-by-step explanation:

The type of mechanism of sex determination illustrated by the example of the blue-head wrasse, where a female can become a male, is known as sequential hermaphroditism.

Sequential hermaphroditism occurs in some fish, crustaceans, and mollusks, where an individual may change their sex during their lifetime, in response to environmental or social triggers. In the specific case of the blue-head wrasse, when the dominant male is removed, a female wrasse will transform into a male to fulfill the missing role. This contrasts with genetic sex determination, which is determined by chromosomes such as XX or XY in mammals, or ZW and ZZ in birds, and environmental sex determination, which may depend on factors such as temperature during critical development periods, such as in some reptiles. The process of sex change in sequential hermaphrodites involves complex hormonal changes that restructure the reproductive organs.