living things
living things have some common characteristics, they can move, grow, reproduce, react to stimuli and excrete, they also need air and food.
there is a wide variety of living things on Earth.
living things have special body features and behaviours that help them adapt to their habitats.
variations exist (exist/do not exist) within the same kind of living things.
we can use a bar chart to show the distribution of variations for easy analysis.
scientists classify living things according to their similarities, classification helps scientists study living things in an orderly way.
animals can be classified into vertebrates and invertebrates according to whether they have a backbone.
vertebrates can be classified into fish, amphibians, reptiles, birds and mammals.
plants can be classified into flowering plants and non-flowering plants according to whether they produce flowers.
the classification system is subject to change when there are new discoveries. that is why people say that scientific knowledge is changing continually.
a key helps us identify living things according to their characteristics.
living things that are in danger of extinction are called endangered species.
some living things become endangered because
their natural habitats are destoryed.
they are excessively hunted or over-exploited.
they have to compete with foreign species.
the environment is heavily polluted.
conservation of wildlife and their habitats is important because:
living things are interdependent for survival. the loss of any kind of living things can disturb the stable system in nature.
humans are dependent on other living things for supply of food, medicine, etc.
measure of conserving wildlife include carrying out studies about wildlife. protecting wildlife by laws, setting up and managing protected areas. reducing pollution and educating the public.
characteristic
habitat
variation
classification
flowering plant
invertebrate
key
non-flowering plant
vertebrate
conservation
endangered species
extinction
interdependence
pollution
wildlife
