Question: 176 Which of the following is characteristic feature of cockroach regarding sexual dimorphism ?
(1) Presence of sclerites
(2) Presence of anal cerci
(3) Dark brown body colour and anal cerci
(4) Presence of anal styles
Answer: Option (4)
Explanation:
Sexual dimorphism refers to the presence of distinct differences between males and females of the same species.
In cockroach, both males and females possess sclerites and anal cerci, so these features do not indicate sexual dimorphism.
Body colour is also similar in both sexes and hence is not a distinguishing feature.
Anal styles are present only in male cockroaches and are absent in females.
Therefore, presence of anal styles is a characteristic feature showing sexual dimorphism in cockroach.