1. TRIVIA
I LIKE TO TWIRL MY BODY, BUT KEEP MY HEAD UP HIGH. AFTER I GO IN, EVERYTHING BECOMES TIGHT. WHAT AM I?

2. Frogs, toads, salamanders, newts, caecilians
CLASS
AMPHIBIA
Frogs, toads, salamanders, newts, caecilians

3. General Traits
A. Amphibia means “double life”.
B. Live part of life in/near water.
C. Live on all continents except Antarctica

4. External Structures
Skin
1. Glands keep skin moist
2. May be poisonous to deter predators
3. Chromatophores-
help change colors
for camouflage.

5. A. Adapted for support against gravity.
Skeleton & Locomotion
A. Adapted for support against gravity.
B. Some adapted for jumping
C. Salamanders & newts:
legs out to side of body-
makes it harder to run fast.

6. Digestion/Nutrition
Young amphibians- herbivores
Adult amphibians- carnivores
Land- detect prey by sight
Water- detect prey by smell

7. E. Use tongue to capture prey in a flip & grab mechanism.
Tongue is sticky to ensure capture of prey.

8. 1. Left atrium- brings O2 rich blood from lungs and skin
Circulation-
A. 3 chambered heart
1. Left atrium- brings O2 rich blood from lungs and skin
2. Right atrium- brings O2 poor blood from body
3. Both atria dump into 1 ventricle which has 3 narrow chambers that keep blood somewhat separate.
4. Carotid artery takes O2 rich blood to brain
5. Pulmocutaneous artery takes O2 poor blood to lungs & skin
6. Aortic arches carry mixture of blood to rest of body.
Frog Heart circulation

9. Lt atrium Ventricle Rt atrium Carotid artery Aortic Arch
Pulmocutaneous artery
Rt atrium
Lt atrium
Ventricle

10. A. Young- external gills that dissolve during metamorphosis.
Gas Exchange-
A. Young- external gills that dissolve during metamorphosis.
B. Adults-
1. Subcutaneous- thru skin
2. Simple sac-like spongy lungs
3. Must live in/near water to help breathe
External gills

11. Nervous/Sensory-
A. Brain
1. Cerebrum- olfaction (smell), color change, visceral function
2. Cerebellum- sense information sent to different parts of brain
3. Medulla oblongata- motor coordination, regulation of heartbeat & respiration
B. Skin- receptors for temperature & pain

13. C. Chemoreceptors in skin, nostrils, tongue, & mouth detect mates & food.
D. Lateral line system present in young.
Vision:
1. Sight feeders
2. Eyes on top of head- see while submerged.
3. Rods & cones in eyes- suggest they can see some color.
4. Nictitating membrane- 3rd eyelid that protects & cleans eye.

14. Tympanic membrane
Flat hearing organ behind eyes
Picks up air vibrations, sends to
Middle ear, inner ear, then brain

15. Temperature Regulation
A. Ectothermic- depend on external sources of heat to control body temp.
B. Methods to maintain temp.:
1. Nocturnal
2. Live near water
3. Burrow in mud

16. Excretion
A. Kidney
B. Wastes passed thru ureter to bladder to cloaca
C. Cloaca is common area for passage of liquid waste, solid waste, & gametes.

17. Water conservation very important a. Nocturnal
b. Live near water
c. Tuck limbs under body to reduce surface area being exposed to sun
d. May form cocoon of shedded skin
e. Flatten body on moist surface to absorb water.

18. Reproduction & Development
A. Fertilization- external
B. Development of egg- external
C. No covering for eggs, so must be laid in water to keep them moist
D. Breeding done in spring & summer during rainy season.

19. Vocalizations 1. Attract mate 2. Establish territories
3. Warn of danger
4. Calls are species specific
5. Females reciprocate call to tell whether they are ready for mating
6. Males have vocal sacs to amplify sound.

20. Bullfrog
bullfrog
Carpenter frog
carpenter frog

21. Grey tree frog
grey tree frog
Spring peeper
spring peeper

22. Northern Leopard Frog
leopard frog
Wood frog
wood frog

23. F. Males generally take care of eggs
F. Males generally take care of eggs. Keep them cleaned, moistened (land), protect from predators, remove dead/ infected eggs.

24. 1. Eggs- millions enclosed in
Metamorphosis
1. Eggs- millions enclosed in
jelly-like substance. Makes them harder to eat.
Salamander eggs

25. Larvae- tadpoles External gills No limbs Tail
Yolk sac- food for developing tadpole
herbivores

26. Adult a. Has lungs b. 2 front legs c. 2 powerful hind legs (frogs)
d. No tail
e. carnivores

27. ORDERS OF
AMPHIBIANS

28. Order Caudata Ex: salamanders, newts Have tail throughout life
2 pairs unspecialized legs
Found in moist areas, under logs, leaf litter
Reproduction- internal fertilization
a. Male deposits sperm cap.
b. Female picks it up & holds it in a sac called spermatheca
c. Lay eggs in strings or lumps
d. Aquatic larva look similar to
adults

29. Order Gymnophiona Ex: caecilians No legs Worm-like with segments
Live in tropical regions & feed on worms
Blind- skin covers eye
Reproduction- internal fertilization
Larva are retained in females where they scrape oviduct lining with fetal teeth.
Born as miniature adults

30. Order Anura 1. Ex: frogs, toads 2. No tails
3. Strong hind limbs, webbed feet, some have claws
4. Live in moist environments- some in desert
5. Reproduction- external fertilization
Toads- dry, warty skin & more inland
Frogs- moist, smoother skin & more close to water,

31. Amphibians in Peril Frogs and salamanders are disappearing fast!
Factors that decrease their populations:
Clear cutting forests dry out their moist environments.
Mining, drilling, agricultural & industrial operations, & urban sprawl destroy habitat.
Acid rain (below pH 5) from air pollution kills eggs & tadpoles.
UV radiation from destruction of ozone layer kills eggs & tadpoles.
All forms of pollution may cause mutation of eggs/tadpoles. See next slide….

34. Maxillary teeth
Vomerine teeth
Eustachian tube openings (to the tympanic membrane)
Vocal sac openings
Lower jaw
Right lobe of liver
Gall bladder (makes & stores bile)
Bile duct (passes bile from gall bladder to stomach)
Duodenum (1st part of small intestine)
Mesentary (connective tissue)
Ileum (last part of small intestine)
Large intestine
Urinary bladder
Cloaca
Urogenital opening into cloaca
Cloacal opening
Internal nares (nostrils)
Esophagus
Glottis (opening to lungs)
Tongue
Median lobe of liver
Left lobe of liver
Stomach
Pancreas
Pylorus (end of stomach)
Spleen
Coelom (internal body cavity)

36. DAILY QUIZ #2 Frogs have a ____ chambered heart.
a. 2 b. 3 c. 4
Frogs and toads belong to Order…
Anura b. Caudata
c. Reptilia
Subcutaneous respiration occurs through
a. Skin b. Lungs c. kidneys

37. The structure labeled below is the
Amphibians are
a. Endothermic b. ectothermic
The structure labeled below is the
Nictitating membrane
Tympanic membrane
Vomerine membrane