Answer:
the brain stem
Explanation:
the structures of our brain stem, in conjunction with our spinal cord (not a part of our brain) is responsible for involuntary action. Not sure if it generate signals, but hey it's better than no answer.
Explanation:
Dinosaurs are living organisms that depends on the environment for survival. As the asteroid hits the Yucatan Peninsula area about 66 million years a couple of things can happen:
Frictional heating of the surface as the earth collided with the asteroid. This heating will cause surface temperature to rise globally and can induce the phenomenon of global warming. This can lead to release of water from reservoirs on the earth surface and hence flooding.
The impact can lead to increase in surface pressure beyond normal and that which life has adjusted to.
Debris in form of dust will be released into the atmosphere and a global air pollution will occur. Gases useful for life will be highly polluted by the vast amount of dusts and other particles discharged into the atmosphere.
Answer:
1. Higher
2.Contract
Explanation:
If an animal cell is kept in a hypertonic solution, water will move from higher water potential to lower that is from the intracellular fluid into the solution resulting in the contraction of the cell
Answer:
PFFT this might help? sorry if not mate
Explanation:
Cell cycle checkpoint controls play a major role in preventing the development of cancer [see Sherr, 1994, for a more detailed discussion]. Major checkpoints occur at the G1 to S phase transition and at the G2 to M phase transitions. Cancer is a genetic disease that arises from defects in growth-promoting oncogenes and growth-suppressing tumor suppressor genes. The p53 tumor suppressor protein plays a role in both the G1/S phase and G2/M phase checkpoints. The mechanism for this activity at the G1/S phase checkpoint is well understood, but its mechanism of action at the G2/M phase checkpoint remains to be elucidated. The p53 protein is thought to prevent chromosomal replication specifically during the cell cycle if DNA damage is present. In addition, p53 can induce a type of programmed cell death, or apoptosis, under certain circumstances. The general goal of p53 appears to be the prevention of cell propagation if mutations are present. The p53 protein acts as a transcription factor by binding to certain specific genes and regulating their expression. One of these, WAF1 or Cip1, is activated by p53 and is an essential downstream mediator of p53-dependent G1/S phase checkpoint control. The function of p53 can be suppressed by another gene, MDM2, which is overexpressed in certain tumorigenic mouse cells and binds to p53 protein, thus inhibiting its transcriptional activation function. Other cellular proteins have been found to bind to p53, but the significance of the associations is not completely understood in all cases. The large number of human cancers in which the p53 gene is altered makes this gene a good candidate for cancer screening approaches.
