| A | B |
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| What is biological variation? | The differences between living things of the same species. |
| Give examples of different species. | Humans, Dogs, Cats. |
| Which is greater, variation between species or within species? | Variation between species. |
| What are the two types of variation? | Continuous and discontinuous variation |
| Give examples of continuous variation. | Height, weight, foot size. |
| Give examples of discontinuous variation. | Sex, eye colour, blood group. |
| What is continuous variation? | A characteristic of any species with a range of values that changes gradually. |
| What is discontinuous variation? | A characteristic of any species with only a limited number of categories. |
| What curve do you get when you measure continuous variation? | Bell shaped curve |
| What is inherited variation? | Variation in a human characteristic that occurs as a result of inheritance from the parents. |
| Give examples of inherited characteristics. | Eye colour, hair colour, skin colour, lobed or lobeless ears. |
| What is environmental variation? | The characteristics of species that are affected by factors such as climate, diet, accidents, culture and lifestyle. |
| Give examples of environmental variation. | Your language, race and religion. Your weight. Flower colour in hydrangeas - these plants produce blue flowers in acidic soil and pink flowers in alkaline soil. |
| What is natural selection? | Species gradually evolve by a process of natural selection. The individuals in any population with the inherited features best suited to the environment in which they live are most likely to survive and reproduce. When they do, they pass on the genetic information for these features to their offspring. |
| What is artificial selection? | Artificial selection, involves breeding animals to select out specific characteristics. |
| What is another name for artificial selection? | Selective breeding. |
| Give some example of artificial selection. | Cows that produce a lot of milk, hens that lay big eggs of a particular colour, cattle that produce lots of meat, tomato plants that produce lots of tomatoes, crops that are resistant to certain plant diseases. |
| What are the two causes of variation within a species? | Inherited and environmental variation. |
| How much of their inherited features do children get from each parent? | Half from each parent. |
| How does the child get formed from both parents at the time of fertlilisation? | Each egg cell nucleus and each sperm cell nucleus contains half of the genetic information needed for an individual. During fertilisation, the nucleus from the sperm cell joins with the nucleus in the egg cell, and a new nucleus is formed with all the genetic information needed for an individual. |
