Mr and Mrs Smith's Life Science: Frog Dissection

Name ________________

Mr and Mrs Smith's Life Science: FROG DISSECTION

Laboratory Lesson #1 Mouth

Pry open the mouth with the probe.

Loosen the jaw by on each side of the jaw with the scissors.

1. Label these internal structures of your frog’s mouth.

FrogMouthDiagram.GIF (4856 bytes)

Answer these questions.

Where is the tongue attached in the frog’s mouth? ________________
How many vomerine teeth does your frog have? ________________
How many internal nares openings can you find in the mouth? _____
What part of the mouth are the maxillary teeth found in? __________
What are the two round bumps that are found on the right and left sides of the frog’s upper jaw ( roof of its mouth)? _______________

7. Draw a picture of the frog’s tongue.

DISSECTION AND EXAMINATION OF FROG’S INTERNAL ANATOMY

Laboratory Lesson #2 Internal Structures of the Frog

Turn the frog over on its back. Using 4 dissection pins pin each hand and foot to the dissecting tray.

Using the forceps, scalpel, scissors, and Cutting Diagram picture from the yellow study guide page 6, cut the frog’s skin.

Pin or remove the skin.

Cut the chest muscles the same way as the skin.

Pin or remove the chest muscles.

Use pages 7 & 8 of yellow booklet to help locate organs.

CIRCULATORY SYSTEM

HEART

8. Draw the parts of the liver and the heart as you see them in the frog.

LIVER

What color is the liver? ________________
How many parts, or lobes, does the liver have? ________________
What organ of the frog’s body is located directly above the middle part

of the liver? _________________

GALL BLADDER

Gall bladder is attached to the back surface of the liver. Lift up the liver to locate it.

12. What color is the gall bladder? _________________

13. Open up the gall bladder. Was it filled with liquid? _______

14. What organ was the gall bladder found under? _________________

DIGESTIVE SYSTEM

If you have a female frog with ovaries containing eggs, read Part E Reproduction from the yellow study guide and remove the eggs before going on.

ESOPHAGUS

15. Where does the esophagus start? _________________

16. Where does the esophagus end? _________________

17. What color is the esophagus? _________________

PANCREAS

18. What color is the pancreas? __________________

19. What 2 major parts of the digestive system is the pancreas attached to?

________________ and _________________

STOMACH

Lift the left lobe of the liver to find the stomach

20. What color is the stomach? _________________

21. What 2 parts of the digestive system is the stomach connected to?

_________________ and _________________

Remove the stomach from the frog.

22. Draw the shape of the frog’s stomach.

23. Touch the stomach. Describe how it feels. _____________________

Using the scissors cut the stomach open lengthwise. Spread it open and pin it down on the dissecting tray.

24. Does the stomach have anything in it? _____

If yes, what did you find? ____________________________________

25. What does the internal lining of the stomach look like? _____________

26. Where does the food go after the stomach? ________________

SMALL INTESTINE

27. Is the small intestine straight or coiled? ________________

Remove the small intestine from the frog. DON’T REMOVE THE LARGE INTESTINE YET.
Stretch the small intestine out so it is straight and pin it down.

28. How long, in centimeters, is the small intestine? _______cm

Cut the small intestine open lengthwise.

29. Was there anything in the small intestine? ______

If yes, what did you find? ______________________________

30. Where does the digested food go after the small intestine? ___________

LARGE INTESTINE

31. Is the large intestine straight or coiled? _________________

Remove the large intestine from the frog. Cut the large intestine open lengthwise and pin it down.

32. Was there anything in the large intestine? ______

If yes, what did you find? ______________________________

CLOACA

33. Where is the cloaca located? _______________________

34. The cloaca is a chamber for receiving 3 things: ________________,

________________, and __________________.

FAT BODIES If your frog has them answer these questions.

35. Does your frog have fat bodies? ______

If yes, what color are they? __________________

36. After looking at the amount of fat bodies in your frog, what season of

The year do you think your frog died? _________________

37. What are fat bodies used for? ______________________________

38. Where are the fat bodies attached in your frog? _________________

LIVER…Observed earlier

RESPIRATION

Remove the lobes of the liver from your frog.

LUNGS

The lungs are to the left and right of the heart in the chest area.

39. Draw the heart and lungs.

40. Remove a lung and cut it open lengthwise. Draw what you see.

EXCRETION

KIDNEYS

41. Draw the shape of the kidneys in your frog.

URINARY BLADDER

42. Where is the urinary bladder located? ________________

REPRODUCTION

43. Do you have a male or female frog? ________________

IF YOU HAVE A MALE FROG do #43 and #44

43. Where are the testes located? __________________

44. Draw the kidneys and testes.

IF YOU HAVE A FEMALE FROG do #45 and #46

45. Where are the oviducts located? _________________

46. Draw the kidneys and oviducts.

GOING FURTHER..
IF YOU HAVE TIME: Follow directions from yellow study guide.
Check them off after you do them.

_____ Thighbone: skin and muscle removed, thighbone visible p.10

_____ Eyeball removed p.11 (Back cover)

_____ Brain exposed p.11 (Back cover)

_____ Spinal cord exposed p.11 (Back cover)

WHEN YOU ARE FINISHED..
1. Throw away paper towel, frog, and frog body parts.
2. Set up your table. Look at board.
3. Turn in Frog Dissection Packet.
4. Return your goggles.
5. Throw away your gloves.
6. Go wash hands with soap.