1. Explain why neither cyclins nor kinases alone can cause a cell to progress through the cell cycle.
As cyclin accumulates, it activates their kinases that turn on the pathway to mitotic spindle formation, and so on.
2. How do controls of the cell cycle protect multi-cellular organisms from accumulating large numbers of damaged or defective cells?
The checkpoint control is responsible for multi-cellular organisms for not accumulating large numbers of damaged or defective cells. Checkpoint controls consist of proteins that detect mistakes and damage and quickly halt the cell cycle until repairs are made. When this occurs, the cell is said to be in cell-cycle <span>arrest.
</span>3. What is the difference between a cancerous tumor and metastasis?
Cancer is cause by mutations in the genes that encode these proteins can lead to uncontrolled growth. Cancer is when there is uncontrolled cell growth and reproduction. Metastasis is caused by tumors when they grow and interfere with the surrounding tissue or cells and break off and spread around the body. Cancerous tumors cause metastasis, and tumors are caused by mutations in genes that lead to uncontrolled growth.
4. What are the functions of tumor-suppressor genes and protoncogenes in noncancerous cells?
The genes that encode the checkpoint proteins are called tumor suppressors because they suppress the development of cells into tumors. If mutations inactivate these genes, the cell-cycle break is removed with or without a signal from the outside. Proto-oncogene’s are involved in promoting cell division, mutations can cause them to become oncogenes, or cancer genes which stimulate cells to leave G0 and divide whether or not it is a signal.
Answer:
They used radioactive labeling techniques to build two different types of phage.
Explanation:
In 1952, a set of experiments were carried out by American biochemists Alfred D. Hershey (1908-1997) and Martha Chase. They prepared two separate virus samples, one contained DNA labeled with a radioactive isotope and the other contained protein labeled with a different radioactive isotope. They grew the two types of viruses separately, infected bacteria with the two sets of phages and analyzed the bacteria for radioactivity. From the results obtained, Hershey and Chase concluded that the viral genetic material was DNA and not protein, reinforcing the observations previously made by Avery.
Blood group b would exclude a male from being a father
