Question

14.13 ■ male and female crayfish, ventral views. the first two pairs of swimmerets are greatly enlarged in the male for transferring sperm from the sperm duct to the females seminal receptacle.
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2.1 what advantage might mouthparts of various shapes provide a crayfish?
2.2 are the antennae biramous? are the antennules biramous?
2.3 what two \typical\ arthropod body regions are fused into the cephalothorax?
2.4 is your crayfish male or female? how do you know?
262 exploring zoology: a laboratory guide

Explanation:

2.1 Different - shaped mouthparts allow crayfish to perform various feeding - related tasks like cutting, grasping, and manipulating different food items.
2.2 Antennae of crayfish are biramous, having two branches. Antennules are also biramous.
2.3 The head and thorax are the two typical arthropod body regions fused into the cephalothorax.
2.4 To determine gender, in males, the first two pairs of swimmerets are greatly enlarged for sperm transfer, while in females, there is an opening to the oviduct and a seminal receptacle under the swimmerets.

Answer:

2.1 They enable diverse feeding functions.
2.2 Antennae: Yes; Antennules: Yes
2.3 Head and thorax
2.4 Check the swimmerets and reproductive structures as described above.