Answer:
cell wall
Explanation:
the cell wall helps fighting any bacteria that tries to infect the cell itself.
The nutrients in the soil will increase resulting in healthier crops.
Answer:
Certain fossils, called index fossils, help geologists match rock layers. To be useful as an index fossil, a fossil must be widely distributed and represent a type of organism that existed for a brief time period. Index fossils are useful because they tell the relative ages of the rock layers in which they occur.
Answer: 1. Cyclin-dependent kinases.
2. The activation process is in two steps: binding of cyclin to cdk and then phosphorylation of cdk cyclin.
3. They are activated when cdks sends signals to cell that is pass already into the next stage of the cell cycle.
4. They are inactivated by the combination of P21 and Thr-14/Tyr-15 phosphorylation after uv induced DNA damage.
5. Changes are seen in target protein level when cdks level rises.
6. The targets are protein that promotes cell divisions.
Explanation:
