Answer: A protein domain is a region of the protein's polypeptide chain that is self-stabilizing and that folds
independently from the rest. Each domain forms a compact folded three-dimensional structure. Many proteins consist of several domains.
One domain may appear in a variety of different proteins. Molecular evolution uses domains as building blocks and these may be recombined in different arrangements to create proteins with different functions.
In general, domains vary in length from between about 50 amino acids up to 250 amino acids in length.
The shortest domains, such as zinc fingers, are stabilized by metal ions or disulfide bridges. Domains often form functional units, such as the calcium binding EF-hand domain of calmodulin.
Because they are independently stable, domains can be "swapped" by genetic engineering between one protein and another to make chimeric proteins.
Change in the external Environment may resulted in the changing in the population of beetles.
Normal polarity
Explanation:
Earth's magnetic field used to be twice as strong 1.5 billion years ago as it is today and Earth's temperature other than what the geologists see from the 'normal' pattern. It has been noticed that some volcanic rocks were magnetized in opposite direction to the direction of the local Earth's field. It is clear that the Earth has experienced the normal polarity 1.5 years ago but at that time, the Earth's polarity was poorly understood.
The highest point the medium rises to and a trough is the lowest point the medium sinks to.
Answer;
A) Blood pressure decreases greatly; blood flow to the heart is inadequate, and blood pressure decreases.
Explanation;
-With negative feedback, the output reduces the original effect of the stimulus. While in a positive feedback system, the output enhances the original stimulus.
-Negative feedback is the most commonly used feedback loop in the body. Negative feedback is used to negate or counteract a stimulus without completely eradicating it.
-One key difference between the two feedback is that positive feedback loops are used to eradicate a stimulus. Another key difference is that responses through positive feedback become more amplified over time. So once a stimulus activates a positive feedback loop it is not turned off until the stimulus is completely removed.