Messenger RNA (mRNA) molecules carry the coding sequences for protein synthesis and are called transcripts; ribosomal RNA (rRNA) molecules form the core of a cell's ribosomes (the structures in which protein synthesis takes place); and transfer RNA (tRNA) molecules carry amino acids to the ribosomes during protein.
Answer:
Because they don't have fertilizer.
Explanation:
Well, if this was a long time ago, then farmers did not have fertilizer. So, there are bacteria on the roots of plants that convert nitrogen into a usable form. It's very important for growing, and when farmers harvest the crop, not much of the nitrogen is returned to the land, so it is not as fertile. Fertilizer is largely consisted of nitrogen, so that is why farmers use fertilizers today. But "a long time ago," farmers did not have fertilizer.
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.
1
state the problem
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hypothess (prediction)
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design the experiment
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record and analyze the date
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<span>conclusion (what did you learn)</span>
