This document discusses relationships between living things in an ecosystem. It defines key terms like species, population, and community and explains how they interact. It also outlines the different ways living things obtain food, including producers, primary consumers, secondary consumers, tertiary consumers, and decomposers. Finally, it introduces the concept of food chains to show how food transfers from one organism to another.

1. RELATIONSHIPS BETWEEN LIVING THINGS
1. Ecosystems
When we think of nature we usually think of living things such as
plants and animals.
A SPECIES consists of a group of organisms which can successfully
reproduce among themselves. They
- have similar characteristics.
- appear and behave similarly.
POPULATION is a group of the same species in the same area.
Rarely in nature is a single population of organisms the only
population in a place.
A COMMUNITY consists of all the plants and animals interacting
with their environment.
2. Living things and food
Living things obtain food in differents ways.
 Producers, such as plants and algae, make their food.
 Primary consumers, such as zebras and fish, eat plants and
algae.
 Secondary consumers, such as lions and snakes, eat primary
consumers.
 Tertiary consumers, such as eagles and owls, are secondary
consumers which eat other secondary consumers.
 Decomposers, such as fungi and bacteria, eaat the remains of
other living things.

2. 3. Food chains
Food chains show how food transfers from one living thing to
another in an ecosystem. Look at the diagram.
ram.