Answer:
The two main things happen during Prophase of Mitosis are given below.
1) In prophase stage of mitosis, condensation of chromosomes occurs which is necessary for the formation of daughter cells.
2) Breakdown of nuclei occurs and moves to the opposite poles.
If this phase is not take place during mitosis, the cell will not divide into daughter cells
Which abiotic factor most likely controls where the plants live in this environment ?
Oxygen levels for aquatic animals
Oxygen from the air and oxygen produced by aquatic plants dissolves in water. Without this, aquatic animals would suffocate and die. Healthy lakes and rivers have high levels of oxygen, and polluted waters often have low levels of oxygen. This pollution means that only certain species can survive there such as sludgeworms. These are bioindicator species because their presence or absence informs us about the condition of the habitat.
Carbon dioxide levels for plants
Carbon dioxide is a reactant in photosynthesis which means plants need it to survive. Areas with higher levels of carbon dioxide are more likely to have healthy plants growing. Farmers often release carbon dioxide within their greenhouses to maximise their crop yield. Woodlands often have higher carbon dioxide levels than open grassland, so many plants living in open areas have evolved mechanisms to overcome a shortage of carbon dioxide.
The problems that will receive priority are the physiological needs such as air, food and water.
Maslow's hierarchy of needs is a theory in psychology which organizes people's needs according to their priorities. It is represented as a pyramid with five steps which include: physiological(at the base), safety, belongingness, esteem and self actualization.
The physiological needs at the base of the pyramid are the first priorities.
<span>Cells control cell division in order to maintain normal cell function. If something happens to the control of the cell division, the healthy cells will divide uncontrollably. These new cells are cancer cells. </span>
The mutations in three genes are responsible for development of cancers:
1. Mutation in proto-oncogenes. Proto-oncogenes normally signal cells to grow and differentiate. Proto-oncogenes can become oncogenes due to mutations which result in the uncontrollable division of the cells.
2. Mutation in tumor suppressor genes. In normal cells, tumor suppressor genes suppress genes essential for cell cycle and that way they prevent uncontrollable cell division. However, after a mutation in these genes, suppression is lost and the cell may progress to cancer.
3. Mutation in stability genes. In normal cells, they have no role either in cell death or growth, but they control mutation rate. Mutation in stability genes results in situation where all genes, including proto-oncogenes and tumor suppression genes, are more frequently mutated.
