Answer:
Crossing over is termed as a process by which genetic materials are exchanged by non-sister chromatids during meiosis. Crossing over results in the new combination of information in genetic for, the cell for a specific trait. It ensures that organisms are identical from one generation to another.
Explanation:
Atmosphere of the early earth + lighting = paleolightning
Answer:
The atomic number of phosphorus is 15. It has zero charge because it has 15 electrons.
<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.
Answer:
Yes, the species of a lizard can be identified using dichotomous keys.
Explanation:
A dichotomous key is an identification tool used by the biologists especially taxonomists to identify and classify the organisms.
The dichotomous keys are based on the characteristic feature of an organism for which two which contains two contrasting feature. The dichotomous keys are the most common tools used to classify an organism.
A species of lizard can be identified using these keys by selecting the key characteristic feature shown by the species which could be quantitative like weight, height or it could be qualitative like colour. By comparing these characteristics, it becomes easy to identify the species.
