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Genes Evolution
Revision for Year 8 Evolution test
Question | Answer |
---|---|
What does 'biodiversity' mean? | The variety of living things. |
Name an ecosystem that is really biodiverse. | Tropical rainforest. Coral reef. |
Name an ecosystem that has very low biodiversity. | Desert, Antartic. |
Why is a desert very low in biodiversity? | Because it is a very harsh environment and difficult for organisms to live in. |
What is the definition of an ecosystem. | The name given to the plants and animals that are found in a particular location and the area in which they live. |
What does interdependence mean? | The way that organisms depend on each other for basic needs like food and shelter. |
Why is it better for an ecosystem to be more biodiverse? | Having lots of different species means that there are plenty of resources for other populations, including humans. |
What is a species? | A group of organisms which have similar characteristics and can breed with each other to produce fertile offspring. |
What does 'variation' in a species mean. | Differences in characteristics. |
How does a reduction in biodiversity affect humans? | Humans rely on other organisms for many things including food, clothing, shelter, drugs. Any reduction in the number of living organisms will reduce resources for humans. |
What sort of human activities reduce biodiversity? | Destroying habitats. Poisoning rivers and land with pesticides.. Building cities and reducing animal habitats. Climate change. |
How are living things dependent on each other? | For food, shelter ...even for oxygen (plants produce this). |
What does 'evolution' mean? | The development of a species over time. |
What is 'natural selection'? | A process by which organisms with characteristics that are most suited to the environment survive and reproduce, passing on their genes. |
What is a 'vertebrate'? | An animal with a backbone. |
What does ' environment' mean? | The conditions around an organism caused by physical environmental factors. (E.g temperature). |
How do animals adapt to winter? | Hibernation, migration, grow thicker fur. |
What is a predator? | An animal that hunts kills and eats other animals. |
What is a carnivore? | An animal that feeds on other animals. |
What is a herbivore? | An animal that feeds only on plants. |
What is prey? | An animal that is hunted and killed by another for food. |
What will happen to the number of predators (e.g. cheetah) if their prey numbers reduce. | Their population numbers will reduce because there is not enough food for them. |
What will happen to the number of prey if the number of their predators increases? | The number of prey will reduce because more are being eaten. |
What does 'extinction' mean? | A species becomes extinct when there are no more individuals left anywhere in the world. |
How do we know that there were different species alive a long time ago? | From the fossil record. |
What are endangered species? | Species of plants and animals that only have a small population in the world. |
How can we help prevent extinction? | By storing genetic samples of organisms in a gene bank. |
What does 'competition' mean? | When two or more organisms struggle against each other to get the same resource. |
What do plants compete for? | Light, water, space and minerals. |
What do animals compete for? | Food, water, territory, shelter and mates. |
What does 'adaptation' mean? | The changes that plants and animals develop in order to survive. |
What are the features of a mammal? | Warm blooded, has hair, feeds its young milk. |