Answer:
B. Open Stomata
C. Transpiration
Explanation:
Even though plants take up a lot of water from their roots, they lose about 95% of it to the atmosphere in the process known as Transpiration.
Transpiration is done for several reasons: it cools the plant down, it enables plants to access the nutrients in the water as the water moves along the plant and it enables gaseous exchange.
The gaseous exchange happens because carbon dioxide comes in from the same holes on the leaf that the water leaves through to the atmosphere, the open stomata.
A prolonged period of photorespiration would affect a plant, giving a significant evolutionary advantage to plant species in dry climates.
<h3>What is the difference between photorespiration and respiration?</h3>
One of the basic differences between photorespiration and respiration concerns the effect of O2 on the two processes. Respiration saturates when O2 reaches approximately 2%, while photorespiration does not reach saturation in a pure O2 atmosphere.
<h3>Under what conditions does photorespiration occur?</h3>
Photorespiration is an expensive metabolic pathway that occurs when the Calvin Cycle enzyme rubisco acts on oxygen instead of carbon dioxide.
With this information, we can conclude that A prolonged period of photorespiration would affect a plant, giving a significant evolutionary advantage to plant species in dry climates.
Learn more about photorespiration in brainly.com/question/13433623
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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.