The wind is just strong enough to move the sand grains which were sorted by size by the wind. Heavier grains were left in place where as smaller grains were carried away. These grains kept moving till they were concentrated in one place usually up a hill. The grains climb the flat slope on the windward side and then fall off the steep side. The dunes may migrate slowly as this process continues, the grains at the upwind side climb the dune with the help of the wind and then fall down the downwind side.<span>
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1. Regulation of glucose blood levels is an example of negative feedback mechanism.
Negative feedback mechanism is a control mechanism involved in homeostasis maintain, in this case maintenance of glucose blood levels in normal range.
Negative feedback mechanism contains sensory system that detects the changes, control system that responds to change and activates mechanisms of effector system that reverse the changes in order to restore conditions to their normal levels.
• Pancreatic cells-sensors
• Insulin-control system
• Body cells- effector cells
2. Blood glucose levels change throughout the day because of the food consumption, but in healthy individuals levels of glucose are successfully regulated via the mechanism of hormones such as insulin and glucagon in a process called glucose blood regulation.
This tight regulation of pancreatic hormones is referred to as glucose homeostasis. Insulin lowers blood sugar and glucagon raises it.
3. If the beta cells are destroyed by an autoimmune disease (immune system attacks its own cells), there would be no insulin release, and consequently, the glucose blood levels would be increased.
Diabetes type I is a metabolic disorder caused by the destruction of insulin-producing pancreatic beta cells.
Mammals do; I'm in my science class
For the second one it’s B or C, I dunno if phototropism is a real word cuz all the rest are vital.
A: Population
If a group of one certain species are living in the same area they are a population. The same goes for humans, we are the same species and when we live in the same area we say we are part of a population. That’s why you would hear things like “the population of massachusetts is 2million” or whatever it is.
