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Unit 18: Biology Part 1 Page 28 of 60
differently, snakes are basically lay eggs, and they generally
legless lizards, from a biological abandon the eggs shortly after
perspective. laying them.
Reptiles in this group are The somewhat unusual body
characterized by having scales or structure of snakes leads to some
shields on their body and by having unusual characteristics. As was
a lower jawbone that can be mentioned above, snakes have
moved independently from the very flexible jaws. This helps make
braincase. up for the fact that they cannot use
This allows snakes and lizards to limbs to grasp prey, like most
open their mouths very wide, a animals do. Also, because their
trait that is especially noticeable bodies are so long and narrow, if a
when snakes, which also have a snake has two of a certain organ,
very flexible jaw, are eating such as the kidney, they are found
relatively large food, as you can one in front of the other as
see below: opposed to side by side.
Only a small minority of snakes
have venom. Of those that do,
venom is usually used to
immobilize and begin to digest
prey, rather than as a means of
self-defense. Nevertheless, snake
bites can be both painful and
dangerous, so it is always best to
steer clear of snakes (as well as
most other animals) in the wild.
This snake is able to eat an egg Snakes without venom usually kill
whole by moving its very flexible prey by constricting, or wrapping
jaw. their bodies around the prey and
Besides the obvious lack of legs, squeezing tightly.
snakes are distinguished from Lizards can generally be
lizard by the lack of external ears. characterized by having four legs,
Snakes are all carnivorous, movable eyelids, and external ears.
meaning they eat meat of other Some lizards do not have legs, or
animals. Snakes frequently eat have legs that are so small they
rodents, insects, eggs, and even are basically useless. These
other snakes. Almost all snakes reptiles can still be distinguished
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