Answer:
The distribution of water on the Earth's surface is extremely uneven. Only 3% of water on the surface is fresh; the remaining 97% resides in the ocean. Of freshwater, 69% resides in glaciers, 30% underground, and less than 1% is located in lakes, rivers, and swamps.
Explanation:
Answer:
forest ecosystem is whereby the organism live together and interact with each other and their environment. The biodiversity in this ecosystem is reducing due to the following factors:
1. deforestation: if most of the trees in the forest are been cut down without replacement it will affect the animal living there. especially herbivores, they feed on this plant and use it as a hideout.
2. bush burning: if the bush is burnt it may lead the animals to ran away for there safety and some may die of hunger, and some trees and plants may also become weak and die therefore reducing food for other animals.
3. Climate change: Climate change is one of the reasons. As deforestation may lead to climate change and many other factors, Without transpiration and evaporation cloud won't be form and there will be no rain which may lead to draught and finally animal will die and others will migrate.
possible solution to this
1. Avoid deforestation, and bush and plant more trees.
2. the government can also make laws concerning deforestation, bush burning, burning of fosil fuels and tires to avoid climate change.
Answer:
If you apply too much pressure, you can cause redness and abrasions.
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.
Answer:
B. A small fraction of the energy is transferred to higher trophic levels, majority stays in the lower trophic levels
Explanation:
Energy transfer between trophic levels is insufficient. When an organism is eaten by another organism, not all of the biomass of prey forms the biomass of the predator. Majority of the energy is released into environment during cellular respiration. Some of the matter also remains undigested and is not used by the predator. Thus, only 10% of energy available at one level is transferred to the next level. So when we keep on moving up in a food chain, energy available keeps on decreasing.