- Adaptation and Variation
- Species is a group of organisms that can breed together to produce fertile offspring.
- Cacti have a smaller surface area compared to volume to reduce water loss. They have a thick waxy layer and leaves reduced to spines to further reduce water loss. They store water in their thick stem which they survive on and have shallow but extensive roots.
- Fish have gills that take oxygen from the water for respiration. They have tail fins with a larger surface area to propel them through the water and other fins to keep them stable with streamlined bodies so they go through the water with very little water resistance. Fish have a swim bladder that they can adjust the amount of gas in to change their depth in water without using any energy.
- Individuals of the same species will look slightly different.
- The differences are called variation. Some is genetic so it can be passed on with a cause of this being when genes change.
- Genetic changes are known as mutations. They can be caused by outside factors like radiation or by mistakes when genes are copied during cell division.
- If mutations occur in body cell, they have little or no effect. if they occur during the formation of sex cells, the mutation will be passed on to all of the cells of the offspring causing new characteristics which might be harmful or could help them survive.