Answer:
Owls eat shrews. If there are fewer shrews, then the owls have less to eat. With less to eat, they end up breeding less and/or starving more. So a crash in the shrew population will cause a reduction in the owl population.
Explanation:
If a keystone species is removed the whole ecosystem will collapse because it relies on that one species.
Pesticides may end up in water sources (such as rivers and the sea), as a consequence they end up in the food chain. Not only this, human water systems could be affected, resulting in humans ingesting these pesticides.
Pesticide presence increases as you go up the food chain because more food will be consumed (e.g: The larger fish may eat several small fish who are contaminated with the pesticide).
Example:
Algae (absorbs pesticide)—> small fish —> Larger fish —> Human
Hope that helped <3
A, decomposition. soil is used for the three others
Explanation:
Bones provide support for our bodies and help form our shape. Although they're very light, bones are strong enough to support our entire weight.
Bones also protect the organs in our bodies. The skull protects the brain and forms the shape of the face. The spinal cord, a pathway for messages between the brain and the body, is protected by the backbone, or spinal column. The ribs form a cage that shelters the heart and lungs, and the pelvis helps protect the bladder, part of the intestines, and in women, the reproductive organs.
Bones are made up of a framework of a protein called , with a mineral called calcium phosphate that makes the framework hard and strong. Bones store calcium and release some into the bloodstream when it's needed by other parts of the body. The amounts of certain vitamins and minerals that you eat, especially vitamin D and calcium, directly affect how much calcium is stored in the bones.