Biology B3

Adaptation and Variation A Species is a group of organisms that can breed together to produce fertile offspring. Species adapt to their environments- Animal and plant species survive in many different environments. They can do this because they have adapted to their environment. Adaptations make individuals of a species more likely to survive and go on to produce offspring this then makes it more likely that the whole species will continue to exist in its environment. Cacti have a rounded shape giving them a small surface area compared to their volume to reduce water loss. They've got a thick waxy layer called a cuticle to further reduce water loss. They store water in their thick stem which they can use when not a lot is around They have shallow but very extensive roots which ensures water is absorbed quickly over a large area. Fish have gills that extract oxygen from water for respiration. They have tail fins with a surface area to help propel them through the water. They use their other fins to keep them stable as they move. Fish have an organ called a swim bladder (or air bladder). They can adjust the amount of gas in their swim bladder to change their depth in the water without having to use any energy.