1. BIOLOGY Unit 9-Crayfish Notes

4. Chelipeds Appearance: Large pincher-claws Location: By the head.
Function: Used to grab food.

5. Carapace Appearance: Hard, red shell Location: Outside body.
Function: Protect delicate internal organs.

6. Swimmerets Appearance: Tiny feather-like legs Location: Belly-side
Function: Help with swimming + grasping during sex.

7. Uropods & Telson Appearance: Fan-like tail Location: Rear end
Function: Propel during swimming.

8. Mouth Appearance: Tiny lips  Location: Uhh…. The head (duh)….
Function: Uhh… eating…

9. Maxillipeds Appearance: Tiny claws Location: Under head and Chelipeds.
Function: Bring food to mouth.

10. Encephalon Appearance: Fleshy bit
Location: Directly inside head, by eyes.
Function: (Brain) Control all other organs + respond.

11. Green Gland Appearance: Fleshy Bits
Location: 1 on each side of head behind eyes
Function: Secrete enzymes needed to digest food.

12. Stomach Appearance: Fleshy Sack Location: In between Green Glands.
Function: Grind up food (uses teeth-like structures).

13. Digestive Gland
Appearance:
Location:
Function:

14. Heart Appearance: Light brown flap.
Location: Behind stomach and digestive glands.
Function: Pump + circulate blood across organs.

15. Antennae Appearance: 2 long stalks Location: Front of head.
Function: Sensory reception.

16. Intestine & Anus Appearance: Skinny tube
Location: Leaving stomach, going down back.
Function: Absorb nutrients + carry waste out of body.

17. Gonads
Appearance:
Location:
Function:

18. Male Parts Appearance: Tiny, bent legs Location: Belly
Function: Insert sperm into female

19. Female Parts Appearance: Swollen hole
Location: Belly, in between swimmerets
Function: Take in sperm (like vagina)

20. Gills Appearance: White colored feathers
Location: Sides of head, under shell.
Function: Remove oxygen out of water for breathing.

22. --Dissection Notes-- Lay crayfish on its belly.
Find carapace behind head.
Cut along lines + gently remove carapace.
Identify internal + external organs.

23. External Dorsal:

24. External Ventral:

25. Sex:
MALE
FEMALE

26. External (Lateral):

27. Internal (Dorsal):

28. Deeper Internal (Dorsal):

29. Internal (Lateral)

30. Abdomen (Dorsal):