Aqa Gcse Biology Paper 2 Study Guide Rated A+

Name the hormone that is released if blood sugar is too low. {Ans: Glucagon}Name 7 abiotic factors and how they might affect a community {Ans: 1. Light intensity - photosynthesis, breeding cycles linked to day length 2. Temperature - photosynthesis/plant growth, therefore animals which can survive 3. Moisture levels - both plants and animals need water to survuve 4. Soil pH and mineral content - distribution of plants, most struggle to grow where there is few mineral ions; low pH inhibits decay and therefore release of mineral ions 5. Wind intensity and direction - shape of trees and landscape, increases plant transpiration 6. Availability of oxygen - aquatic animals e.g. fish require high levels of dissolved oxygen 7. Availability of carbon dioxide - photosynthesis}What is Variation ? {Ans: inherited differences in Organisms caused by genetics or environmental factors}What theory did Charles Darwin come up with? {Ans: Evolution by Natural selection Variation in species phenotype caused by mutations. Organisms with the most suitable characteristics/better adapted for the environment would be more successful competitors and be more likely to survive. They are more likely to reproduce,passing on the genes for their beneficial characteristics to offspring. Overtime the beneficial