2. Draw a diagram of the frog showing the external features listed below.

2. Using the coloring pages identify the following external parts: Describe each in your log

a) nostril j) front limbs

b) adhesive pad on male thumbs k) jumping legs

c) brow spot

d) trunk

e) eyelid

f) cloacal opening

g) nictitating membrane

h) digits ( toes and fingers- note webbing)

i) tympanum membrane

3. Determine the sex of you animal. Male ( ) female ( )

4. Force open the frog’s mouth and exam the internal structures. Using the large pair of scissors cut the jaw on either sides of the mouth. This will allow you to open the mouth all the way and to see the internal structures better.

5. Locate and describe the following structures:

a) tongue:

b) maxillary teeth along the jaw

c) vomerine teeth found in the roof of the mouth

d) Internal nares

e) Eustachian tube

f) opening of vocal sac (only in males

g) glottis

6. Lift the tongue with forceps near glottis and observe its attachment to the floor of the mouth. Speculate why it is this way.

7. Explain how the frog snares its victims.

8. Measure the length of the following:

length of body

width of body

length of forearms

length of the longest digit on the forearms

length of jumping legs

length of the longest digit on the jumping legs

9. Using a fine pair of scissors cut the skin only along the stomach as shown on the slides. Remove most of the skin from the trunk area.

10. Describe the muscles on the abdomen in comparison to the dorsal side.

11. Pin the frog to dissecting pan ventral side up as shown in you lab books on page 139.

12. Using your scalpel cut a small opening through muscular body wall at Point C. After you have made the opening use your fine scissors and insert the tip of the scissors into the incision. Holding scissors almost parallel to the body continue cutting to point A. At this point you will find the bony sternum. Stop here and exam page 140 in your lab book for additional information.

13. After all the incisions have been made and the body muscles have been pulled back take a minute and describe the following.

a) wall muscles of the ventral side of the frog

b) Pectoral girdle

14. Locate, describe and remove the fatty bodies in the frog.

15. Without removing any organs locate, describe the following digestive organs and explain their function.

see page 142 in your lab book.

a) liver

b) gall bladder

d) esophagus

e) stomach

f) duodenum

g) intestine

h) spleen

i) rectum

j) cloaca

k) urinary bladder

15. Carefully cut the esophagus above the liver and cut the cloaca. Remove all the digestive organs without damaging other vital parts.

16. Stretch out the intestine and measure its length. ___________

17. Locate and describe the following circulatory organs:

a) Heart:

b) ventricle

c) auricles

d) dorsal aorta

e) kidneys

Frog dissection instructions -- Part 2

page 1 of 2

18. Locate the hearth. Note the size in relation to the rest of the animal and the fact that it is surrounded by mesentary tissue.

- What are the dimensions of the hearth ( length ______) (width________).

- What is the name of the mesentary tissue that surrounds the heart.

19. Locate the Dorsal aorta ( refer to page 144 in the dissection booklet)

20. Locate the lungs and describe their appearance and explain their function.

21. How does the frog force air in and out of its lungs?

22. Remove the heart and slice it laterally (the long way) into two parts.

23. Describe the chambers of the heart.

24. How many chambers does it have?___________

25. Locate the kidney. Describe their appearance and explain its function.

26. Remove the remaining organs from the visceral cavity.

27. To expose the brain follow the instructions CAREFULLY that are found on page 149 in your booklet.

28. Locate, describe and explain the functions of the following structures.

OLFACTORY LOBE

CEREBRUM

OPTIC LOBES

CEREBELLUM

page 2 of 2

29. Remove the eyeball , intact from the frog.

30. Describe its shape color and anything else that you might note.

31. Cut open the eyeball so that you don’t damage the lens.

32. Describe the shape of the lens.

33. Compare this lens with those from sharks and fish.

34. Using your scalpel and scissors remove as much muscle tissue from the frog’s leg. You are trying to expose the bones found in the leg so be careful.

35. Describe the bone structures that you find in the upper and lower parts of the leg.

36. Using your scalpel cut the spinal column so that you sever the frog into two parts.

37. Exam the spinal column. Describe what you see. (a diagram here would be nice)