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Biology
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Explain through Darwin's Theory of evolution how species become better adapted to their environment.

Darwin's Theory suggests that all populations have variation between them, this variation is primarily caused by mutations in DNA. If an individual within a species gains...

CS
Answered by Caitlin S. Biology tutor
2615 Views

What happens during eutrophication?

The addition of nutrients such as nitrate means that nutrients no longer limit plant growth.Algae begins to bloom which blocks out sunlight. As a result, plants cannot photosynthesise (or photosynthesis i...

EC
Answered by Emily C. Biology tutor
2606 Views

Why does as an excess of nutrients such as nitrates lead to animal death in bodies of freshwater?

This is an unexpected result as usually nutrients are considered beneficial to organisms. Some organisms do benefit enourmously from the nutrients, but this leads to the deaths of other. The high concentr...

DA
Answered by Daniel A. Biology tutor
2866 Views

How is immunity developed after a primary infection by bacteria?

Phagocytosis - A phagocyte detects the bacteria has foreign antigens and so envelops it with its cytoplasm, packaging it into a phagosome via endocytosis. Lysosomes then fuse with the phagosome releasing ...

DV
Answered by Daniel V. Biology tutor
2401 Views

In some parts of Africa, where malaria commonly occurs, there are higher frequencies of the allele that causes sickle-cell anaemia.

Individuals with the recessive sickle-cell anaemia allele have a lower chance of developing severe malaria. Therefore, they are more likely to survive and reproduce than those without the allele. The alle...

LN
Answered by Laura N. Biology tutor
2337 Views

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