Transcript Reptiles and Amphibians

A.
B.
C.
D.
E.
Usually a smooth moist skin
Aquatic eggs and gilled larvae
Metamorphosis takes over to convert gills to lungs.
Ectothermic – they are cold blooded.
MUST reproduce in
moist conditions.
F. Some have eliminated land
or water forms.
G. A few store the eggs on
parents’ moist bodies.
Apoda means without feet
A. 160 species occurring in tropical forests of South America, Africa, and SE
Asia
B. Small eyes; most adult forms totally blind
C. Special sensory tentacles on Snout
D. Fertilization is internal with males having a protrusible organ
E. Eggs of Oviparous species usually laid in very moist soil
F. Viviparity is common in this group
Means : “Having a tail”
A. 360 species of tailed amphibians
B. Most less than 15 cm, but some over
1.5 meters
C. In some forms, limbs are absent or
rudimentary
D. Carnivorous as larvae and adults
Three-toed Amphiuma
Amphiuma tridactylum
E. Some are wholly aquatic- most are metamorphic to various land
forms.
F. Eggs fertilized internally after female picks up sperm pack
(spermatophore) from male
G. Aquatic forms lay their eggs in water / terrestrial in very moist soil
H. Most complex life cycles seen in North America – Aquatic larvae
metamorphose to form juvenile land forms, which
metamorphose again into aquatic breeding adults.
HOWEVER - some skip the juvenile land stage and remain
aquatic.
(juvenile)
I. Vascular networks in skin serve to carry out respiration
J. Salamanders may have lungs, gills, both, or neither
K. There are aquatic forms that breathe primarily with lungs, and
terrestrial forms with no lungs at all.
L. Plethodonts live their entire life on land, but have no lungs. They
pump air in and out of their mouth where gas exchange takes
place in vascular tissues of the mouth ( buccal cavity breathing)
M.Paedomorphosis – means “child form” These Salamanders become
sexually mature without ever becoming adults. They are often
called Perrenibranchiate (permanently gilled). The best example
is the Necturus Mud Puppy.
N. Some metamorphose to adult
forms only in certain conditions
such as drought or when exposed
to certain chemicals. The best
example of this is the axolotl.
axolotl
A. 3,450 species ; evolved from Tetrapods
B. 21 Families: most common :
1. Ranidae – true frogs
2. Hyalidae – tree frogs
3. Bufonidae – toads
C. Males sing during breeding season , especially after rain
D. Hibernation at bottoms of ponds during winter
E. Endoskeleton bony with some cartilage
F. Most breathe using floor of mouth and skin
G. Fused caudal vertebrae called urostyle
H. Reproduction external through clasping called amplexus
I. Frogs lay eggs in clumps, toads in spiral strings.
J. Most have smooth moist skin – many with toxic
glands known as serous glands. All have mucous glands.
K. Double circulatory system with 3 chambered heart and spiral valve.
Dendrobates pumilio – The Strawberry Poison Dart Frog;
known as Mr. Blue Jeans to the Ticos of Costa Rica.
Spiral valve controls where
blood flows!
Frog and Toad breathing is
really strange!
Fowler’s Toad – Bufo woodhousii
One of Mississippi’s common toad species
A. Dominated the Mesozoic Era: The Age of Reptiles
B. Characterized by tough dry scaly skin rather than moist like
amphibians
C. Most important advancement
was the Amniotic Egg
D. All reptiles have copulatory
organs for internal fertilization
E. Reptiles have better developed
circulatory and respiratory systems
F. NO cutaneous (through skin) respiration like in amphibians
G. Urine semisolid and contains uric acid. More advanced!
H. All reptiles with legs have claws, unlike amphibians
I. Snakes have special sense of smell with Jacobsen’s organs.
A. Body encased in fused shell made of Keratin
B. Carapace is the dorsal shell which contains the fused
vertebrae
C. Plastron is the bottom or ventral shell
D. Have both middle and inner ears – poor hearing
E. Oviparous: ALL bury eggs in ground
F. Sex determined by incubation temps – high = females; low = males
G. Low metabolism – long life spans 0f 150 -200 years not unlikely
H. Alligator Snapper “lures” its prey with wormlike tongue extension
I. Turtles don’t have teeth; just sharp jaw bones.
Suborder Sauria - Lizards
A. Presence of kinetic (moveable) skulls for feeding
B. Lizards are greatly diverse: aquatic, terrestrial, arboreal,
burrowing, even aerial!
C. Geckos – toe pads let them walk upside down; no eyelids
D. Iguanas – New World lizards with throat fans, frills and crests
E. Skinks – long bodied; short limbed; sleek and fast.
F. Chameleons – arboreal with long tongue; body length or more
G. Glass Lizards – no feet or legs!
H. MOST have moveable eyelids; external ears
I. Color vision
J. Skin lacks glands, semisolid urine helps prevent water loss.
http://www.youtube.com/watch?v=JF-UMgdkph4
Galapagos Marine Iguana
A. Lack limbs; except for some pythons’ and boas’ vestigial legs
B. Cornea covered by a spectacle; which is shed with skin
C. Lack external and middle ears, but DO have inner ears
D. Most common types of movement
1. lateral undulation- s –shaped
pushing off ground surface
2. rectilinear– using belly muscles
3. sidewinding – used in desert to
minimize ground contact
4. concertina – used to move up
between walls, corners, etc.
1. Crocodilians have a four chambered heart, while
all other reptiles have a three chambered
heart.
2. High temps in alligators result in males being
born, while low temps result in females.
3. Females protect their young very adamantly.
4. Crocodiles are aggressive; alligators are not.
Test next time!