7D Variation and Classification_2017-04-05 10-21-1464.PPTX

Variation and Classification_2017

1. Biology Variation and Classification

2. Variation and Classification Contents Spotting variation What causes variation? Summary activities The classification system

3. What are the differences between these organisms? Spot the differences

4. There are lots of differences between these organisms. For example: some have leaves; some lay eggs; some eat plants. These organisms are different because they are all from different species . Spot the differences

5. There are also differences between organisms of the same species . For example, these people are all from the same species but how many differences between them can you spot? Spot the differences – same species

6. Even though people are all from the same species, there are many ways in which they are different from each other. Some of them are male, some are female, some are tall, some are short. The differences that occur both between different species and within the same species are called variation . What is variation?

7. Contents Spotting variation What causes variation? Summary activities The classification system Variation and Classification

8. Variation is caused by two factors: Some features are cause by inherited factors . These are features that are passed on from parents . For example, natural hair colour is an inherited feature. 2. Some features are caused by environmental factors . These are features that are affected by the surroundings . For example, someone can be born with brown hair which then gets lighter in the Sun or might be dyed a different colour. What causes variation?

9. Environmental or inherited?

10. Sometimes it is not easy to determine whether a feature is inherited or environmental. Scientists have now decided that only four characteristics are truly inherited and not affected by the environment at all. Can you guess what they are? Environmental or inherited? natural eye colour natural hair colour blood group some inherited diseases

11. Some features are caused by a mixture of inheritance and the environment, for example, nose shape . Someone might have a nose that looks just like their mum’s. How can the environment affect skin colour ? What about other features? But if they were in an accident, they might break their nose and put a kink in it. So their initial nose shape was probably inherited but over time it is likely to have been affected by the environment.

12. Contents Spotting variation What causes variation? Summary activities The classification system Variation and Classification

13. There is a lot of variation between organisms, but some organisms also have many features in common. How many features common to both cows and dolphins can you think of? Common features Compare a cow and a dolphin , you might think they do not have many things in common but you will be surprised.

14. Common features

15. Cows and dolphins have several features in common. Grouping organisms based on their common features is called classification . What is classification?

16. Sort these organisms into four groups based on their similarities . Classification – grouping organisms

17. One way that a scientist might have grouped these organisms is to put them into the following four groups: These groups come from the scientific system for classifying organisms. Classification – grouping organisms Plants Birds Mammals Reptiles

18. The classification system begins with very big groups that include a lot of organisms and then moves down to smaller groups made up of fewer organisms. The biggest groups are called the kingdoms . All living things are classified into five different kingdoms. The classification system plants protoctista animals monera fungi living things

19. The five kingdoms

20. Which kingdom?

21. Classifying animals How can different types of animals be classified?

22. Animal classification Invertebrates Vertebrates Animals Invertebrates are animals that do not have a backbone. They have soft inner bodies which are held in shape by a flexible covering of outer cells or by a hard covering called an exoskeleton . Vertebrates are animals that have a backbone . They have a firm body because of the muscles that connect to their skeleton. The animal kingdom is divided into two groups:

23. Animal classification

24. Vertebrate classification

25. Features of vertebrates

26. Invertebrate classification

27. More about arthropods Arthropods are divided into four subgroups: myriapods – They have many feet and long bodies of many segments, e.g. millipedes, centipedes. arachnids – They have eight legs, no wings and their bodies are in two segments, e.g. spider, mite. insects – They have six legs, and many have two pairs of wings, e.g. dragonfly, moth, ladybird, wasp. Crustacea – They have gills, more than six legs and two pairs of antennae, e.g. crab, barnacle, lobster, shrimp.

28. Animal classification – activity

29. Which classification group?

30. Plant classification

31. Contents Spotting variation What causes variation? Summary activities The classification system Variation and Classification

32. Plenery: