What Is an Animal?
Chapter 9 Section 1

Composed of…
◦ Cells: basic unit of structure and
function of living things
◦ Tissue: group of similar cells that
perform a specific function
◦ Tissues combine to form organs, more
complex job
◦ Organs combine to form systems
Structure of Animals
Obtaining
food and
oxygen
Keepings conditions
stable
Movement
Reproduction
Functions of Animals
 Food
provides animals with raw
materials for growth and energy
 Most animals take food into a
cavity inside their bodies
◦It is then digested/broken
down
 To release energy from food, the
body’s cells need oxygen
Food and Oxygen

a structure or behavior that allows
animals to perform basic functions in their
environments
Adaptations

Some animals move around their
entire life
◦ Humans, frogs, dogs (swim, walk, hop)

Some animals move for part of their
lives
◦ Oysters, barnacles

Why do animals move?
◦ Obtaining Food
◦ Reproducing
Movement
 Sexual
Reproduction
◦ New organisms develops from the
joining of two sex cells (male
sperm cell and female egg cell)
◦ Combination of both parents
characteristics
 What is the joining of an egg cell
and a sperm cell called?
Fertilization
Reproduction

Asexual Reproduction
◦ Process by which a single organism
produces a new organism identical to
itself
 Sea Anemones
 Single-celled organisms such as the
archaea, bacteria, and protists
Reproduction Continued
1.5 million species
 Biologists have classified animals into
about 35 major groups called phylum
 Evidence suggests that all animals
arose from single-celled ancestors
 When classifying, biologists consider
◦ How it looks
◦ How it develops
◦ The content of its DNA

Classification of Animals

Vertebrates
◦ animals with a backbone

Invertebrates
◦ animals without a backbone
◦ 97%
Vertebrate vs. Invertebrate