Chapter Summaries I
Living and Non-ling Things
There are seven characteristics of living things:
breathing or respiration,
Some non-living things may show one or two of these characteristics but living things show all seven characteristics.
Non-living things can be divided into two groups, those which were once part of a living thing and those which were never part of a living
Groups of Animals
The two main groups of animals are the
vertebrates and the
These can be divided into smaller sub groups.
Biologists have to think very carefully about the reasons for grouping animals
Movement and Feeding
Animals move for various reasons, including feeding and escaping from predators.
Nearly all animals belong to one of the following types:
Animals can move in one or more different
ways. The various types of movement are walking, running,
Movement on Land
Animals which move on land can walk, run,
leap, hop or
All vertebrates have a
skeleton made of bone inside their bodies. The skeleton is able to move because of its
Arthropods also have a
skeleton but it is on the outside of their bodies. It is made of
chitin, not of bone. Their
muscles are inside the hard skeleton.
Movement in the Air
Nearly all birds fly and many insects fly. The
bat is a flying mammal.
Flying animals have wings which are moved up and down by the action of muscles.
The bird's skeleton is adapted to help it fly. Its body is covered with
feathers which also help it to fly through the air.
Flying insects have muscles inside the skeleton which move their
wings. They have either one or two pairs of wings.
Some other animals are able to
glide through the air. The
'flying' fish and the 'flying' squirrel are really gliders. They do not have any wings to beat.
Movement in the Water
Fish are adapted for swimming
by having a streamlined shape and fins.
Most mammals which spend a lot of their time in water
have also developed a streamlined shape. They also have flippers to help them move through the water.
Many water insects
have one pair of legs shaped like paddles to push them through the water.
Other animals, such as
frogs, have webbed feet which act as paddles.
Recognizing and Choosing Food
Animals use one or more of their senses to find their food. These senses are
sensitivity to heat.
Some animals only eat one kind of food whereas others have a more varied diet.
Certain animals can eat a variety of food but prefer one type of food to others.
The diet of some animals will depend on the season.
How Animals Feed
Carnivores need to be able to catch and kill their prey before they can eat it. Different carnivores deal with this problem in different ways.
Carnivorous mammals, such as the cat and dog, have
teeth which are specially adapted to help them kill their prey and to tear meat.
Herbivores do not have to ‘catch’ their prey but they have a different problem. Vegetation is tough and needs a lot of chewing to break it down into small pieces.
Herbivores have mouthparts which are adapted to this.
Herbivorous mammals have large back
teeth with wide surfaces. The vegetation is chewed between the top and bottom teeth. The
ruminants chew their food twice.
Some omnivores are
filter feeders, feeding on plankton which is a mixture of microscopic plants and animals.
A few carnivores and herbivores
feed only on liquids.
They have mouthparts especially adapted to suck their liquid meals.
How Food is Digested
When food is taken into the body it is
ingested, digested and absorbed. The non-digestible food is eliminated.
absorbed food is moved to all parts of the body by the
blood. Among other things it provides
energy for the body's activities.
For a balanced diet humans must eat foods containing the following chemicals:
Energy is measured in
Kilocalories or Kilojoules.