Animal classification, vertebrate and invertebrate animals

1. Animals classification
• Animals can be classified according to their
characteristics, such as whether or not they have
a backbone (vertebrates= have, invertebrates=
don’t have)
• Some animals hatch from eggs and others have
live births.
• Trait: a characteristic passed on to a living thing
from its parents.

2. Vertebrate: an animal with a backbone.
Kinds of vertebrates:
Fish: they live in the water, have fins and
scales, lay eggs and breathe through gills.
Amphibians: live in land or water, lay eggs,
have a moisty skin and breathe through gills,
lungs or skin.
Reptiles: lay eggs, are cold-blodded,
have dry, scaly skin.
Birds: have feathers, a beak, 2 legs and
lay eggs.
Mammals: breathe through lungs, have
hair or fur, give bird to young and give
them milk.

3. Invertebrate: animals without backbones.
Kinds of invertebrates:
Sea jellies: have soft bodies and are
made mostly of water.
Worms: have long, soft bodies and no
legs..
Mollusk: many of them have hard shells
and eyes.
Arthropods: are the largest group. It is an
animal that has a hard covering outside the
body (exoskeleton). Insects, spiders and crabs
are arthopods.

4. Offspring are like their parents
Mammals and plants inherit certain
characteristics from their parents. Other
characteristics are acquired.
• Animal behaviors can be inherited or learned.
Inherit: means to receive from a
parent. This characteristic is also
called a trait. Ex: color, shape of
the body.
Instinct: they are inherited
behaviors. Ex: puppies are born
knowing how to suck milk.

5. Animals life cycles
• Some insects and amphibians change form
as they develop into adults. This process is
called metamorphosis.
• Mammals do not change very much as
they become adults.

6. • Larva: is the second stage in the life cycle of some
insects. A butterfly larva is called a caterpillar.
• Pupa: is the stage in an insect’s lify cycle between
larva and adult. A butterfly pupa is protected
inside a hard covering called a chrysalis.

7. • Metamorphosis: is the process in which some
insects and amphibians change form as they
develop into adults.

8. • Unlike amphibians and insects, young mammals
do not change very much as they become adults.
They look like their parents when they are born.