To prevent blood flowing back after each heartbeat. They ensure that the blood flows only in one direction (back to the heart).
Answer;
-Because of Homeostatic imbalance as we age our body organs become less efficient, and our internal conditions become less and less stable. This event has a risk for illness and produce changes we associate with aging.
Explanation;
-Homeostasis is the body's ability to maintain a relatively stable internal environment even though the outside world is constantly changing. It involves both positive feedback Loops and the negative Feedback loops.
-Aging is a general example of disease as a result of homeostatic imbalance. As an organism ages, weakening of feedback loops gradually results in an unstable internal environment. This lack of homeostasis increases the risk for illness and is responsible for the physical changes associated with aging.
Rose is an example of a producer.
I am pretty sure that it is D
With decomposition, the final deposition of particles(sediments) usually occurs at the mouth of a stream. Then a process called horizontal sorting occurs where the sediments that were once carried down are arranged from big to small. Decomposition in streams takes time so the speed of the water and wind should not affect it nor should gravity or the direction. Streams cannot change direction either unless human involement occurs
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