Transcript CLASS REPTILIA - District Five Schools of Spartanburg County

CLASS REPTILIA
CLASS REPTILIA
• All reptiles produce
amniotic eggs in which
the embryo is surrounded
by two protective
membranes. The yolk sac
provides food for the
embryo.
CLASS REPTILIA
• Reptiles conserve water by having a dry,
scaly watertight skin and by eliminating
their nitrogenous wastes as uric acid.
CLASS REPTILIA
• Lizards, turtles, snakes, and
tuataras have a heart with two
atria and one partially divided
ventricle. Crocodiles have a fourchambered heart, as mammals
do.
• Reptiles inflate their lungs by
expanding the ribs, drawing in air
by decreasing abdominal
pressure.
CLASS REPTILIA
• A reptile’s brain is about the
same size as the brain of an
amphibian, but it has a
much larger cerebrum.
• The Jacobson’s organ
detects chemicals picked up
by the tongue.
CLASS REPTILIA
• All living reptiles are
ectotherms.
Ectotherms warm their
bodies mainly by
absorbing heat from
their surroundings.
• Reptiles can keep their
body temperature
fairly constant by
moving into and out of
the sun.
CLASS REPTILIA
• Ectotherms require very little food, but
they cannot live in cold climates or be
active when temperatures are low.
CLASS REPTILIA
• Many reptiles lay shelled eggs. This is
called oviparity.
CLASS REPTILIA
• Some species transfer nutrients and
oxygen to the developing embryos through
a placenta. This strategy is called
viviparity.
CLASS REPTILIA
• Some species retain the eggs inside the
female’s body. This is called ovoviviparity.
CLASS REPTILIA
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Familiar living reptiles are classified into
four orders:
Chelonia
Crocodilia
Squamata
Rhynchocephalia
CLASS REPTILIA
• All turtles (order Chelonia) have a shell
composed of bony plates. The vertebrae
and ribs are fused to the interior surface of
the shell. Turtles are mainly aquatic, while
tortoises are terrestrial. All species lay
eggs.
CLASS REPTILIA
• Crocodilians (order Crocodilia) are large
aquatic or semiaquatic carnivores. This
group includes crocodiles, alligators,
caimans, and the gavial. They eat
whatever they want to eat.
CLASS REPTILIA
• Lizards and snakes belong to the largest
order of reptiles (order Squamata). Most
lizards are small, agile, and feed on
insects.
CLASS REPTILIA
• Lizards can detach their tail (autotomy) in
order to confuse a predator.
CLASS REPTILIA
• Some snakes kill their prey by constriction,
suffocating it with their coiled body. Some
species kill by injecting venom. Snakes
can swallow objects larger than their head
because they have a very flexible skull.
CLASS REPTILIA
• Rhynchocephalia
(RING-koe-suh-FAYlee-uh) is an ancient
order that contains the
tuataras.
• Today tuataras inhabit
only a few small
islands of New
Zealand.
CLASS REPTILIA
• The word tuatara
means “spiny crest” in
the Maori language.
Tuataras resemble
large lizards and grow
to about 60 cm (24 in.)
in length.
• They eat insects,
worms, and other
small animals.
• I like turtles.