1. Monday 5/23/2016
Why do we dissect frogs? What can we learn from it?
What does anatomy mean? What does Physiology mean?

2. The Wonderful World of Frogs!!

3. Q: Why are frogs so good at baseball?
Amphibian Trivia
Amphibians can breathe with skin, gills, or lungs
All amphibians lay their eggs in water
Salamanders, frogs, toads, and caecilians are all amphibians
Amphibians are herbivores
Frogs are the largest group of amphibians
True
False
Q: Why are frogs so good at baseball?
A: Because they catch a lot of flies...

4. Amphibians: animals that can live both on land and in water.
A number of adaptations allow amphibians to live on land.
large shoulder and hip bones
mobile, muscular tongue
breathe through skin or with gills or lungs
How do these adaptations help on land?

5. Amphibians return to the water to reproduce. Why?
Amphibians use many strategies to keep their eggs wet.
lay eggs directly in water
lay eggs on moist ground
wrap eggs in leaves
brood eggs in pockets on the female’s back

6. Metamorphosis tadpoles adult frog young frog or froglet
fertilized eggs
Metamorphosis 4 1 3 2

7. Metamorphosis Tadpoles are aquatic larvae of frogs:
Newly hatched: Live off the yolk in their body
Have gills
2 chamber heart
Mouth will open and allow it to eat
During metamorphosis, tadpoles develop into their adult form:
Hind limbs grow first, Tail reabsorbs and disappears
Mouth broadens: Develops teeth and jaws
Gills are reabsorbed and lungs develop
Heart develops a 3rd chamber

8. Frogs are the largest amphibian group and include toads.
There are over 3000 species of frogs.
Glands in the skin of frogs and toads contain poisons that help to protect them from predators.
Live in all environments except poles and driest deserts
Adult frogs will eat any animal they can catch

9. Anatomy of a Frog: Circulatory System
1. Right Atrium: Receives deoxygenated blood from the body
2. Left Atrium: Receives oxygenated blood from the lungs
3. Ventricle: Both the Left and Right atrium empty into here
Main pumping chamber of the heart

10. Left Atrium
Right Atrium
Ventricle

11. Anatomy of a Frog: Digestive System
Tongue-Mouth-Swallows by pressing eyes to the roof of the mouth (Tongue attached in front of mouth: sticky end)
Teeth
Maxillary Teeth: Perimeter of upper jaw
Vomerine Teeth: Roof of Mouth
Alimentary Canal: Digestion occurs here
Includes: esophagus, stomach, small intestine, large intestine
Small Intestine: Made of three pieces
Large Intestine: Absorbs nutrients
Liver: produces bile, digestive enzyme, stored in the gallbladder
Pancreas: secretes digestive enzymes into the small intestine

12. Mouth
External Nares
Nictitating Membrane
Eye
Tympanic Membrane

13. Internal Mouth

14. Maxillary teeth
Vomerine teeth
Internal Nares
Eustachian tube
esophagus
glottis
tongue

15. stomach
duodenum
pancreas
Small intestine
Large intestine
ileum
spleen

16. Mesentery connecting small intestine

17. Fat Bodies
Small intestine
Large intestine

18. Anatomy of a Frog: Excretory System
CO2 mostly excreted through skin
Waste from food:
Kidneys: Primary excretory organ, filter waste from blood
Water and Nitrogenous waste is called urine, excreted through anus

19. Frog Kidney

20. Anatomy of a Frog: Respiratory System
Respiratory System: Tadpoles use gills; Adult: Use lungs
3 ways to respire:
1.Through Lungs: Pulmonary Respiration
2.Through Skin: Cutaneous Respiration
3.Through Mouth: Diffusion through the lining of the mouth.

21. Anatomy of a Frog: Reproductive System
Male: Testes produce sperm
Female: Ovaries produce eggs
Mating call to attract female
When the female releases the eggs the male discharges sperm on them; direct external fertilization
In 12 days the eggs hatch into tadpoles
Frogs produce tons of eggs…Why?

22. Frog Eggs
Ovaries with Frog Eggs

23. Frog Testes
Testes

24. Heart
Fat Bodies
Urinary bladder
Liver

25. List two reasons why amphibians must live in moist environments.
Compare and contrast the frog heart to the human heart.
List three changes that occur during metamorphosis.
Amphibians are very sensitive to changes in their environment, which is why they are called Biological Indicators. Why might this be?
Why does amphibian reproduction require a moist environment?
List two adaptations of amphibians and briefly describe why each is important for life on land.
List the major structures involved in each of the following systems: Respiratory, Digestive, Reproductive and Excretory

26. Esophagus
Liver
Lung
Gallbladder
Pancreas
Stomach
Small Intestine
Spleen
Large Intestine
Cloacle
Cloacle Opening
Kidneys
Testes
Ovaries/Eggs
Oviducts
Large Intestine
Urinary Bladder
Cloacle Opening

27. 1 4 2 3 10 9 8 7 6 5

28. Mouth
Tongue attached at front of mouth; 2 sets of teeth to hold prey
2. External Nares (nostrils)
at the top of the frogs head; allows frog to breathe while partially submerged under water
3. Forelimbs
for balance; shorter than hind limbs
4. Digit
grasping
5. Eyes
Nictitating membrane: Third eyelid: Keeps eyeball moist and protects eye under water
6. Tympanic membranes
External eardrums; senses vibrations for hearing; transmits sounds to internal ear
7. Dorsal side
“backside”; darker for camouflage
8. Skin
Respiration and protection (camouflage), Mucus Glands: Secretes lubricant that keeps skin moist; Secretes foul tasting or poisonous substance for protection
9. Hind limbs –
used for jumping and swimming; feet are webbed; up to 6x longer than forelimbs
10. Ventral side
“belly” side of frog; lighter in color for camouflage