Biology Answers

what is the importance of coupled reactions?

Distinguish between proto-oncogens and tumor-suppressor genes; give one example of each. In

which class of genes does a loss-of-function mutation predispose cancer? A gain-of-function

mutation? Explain your answer.

How can one reconcile the following statements : “Cancer is a genetic disease” and “Most

cancers are sporadic (not inherited)”.

Describe the role of cyclins, cyclin-dependent protein kinases, and protein degradation in the

progression of cells through the cell cycle

Is the formation of large blebs from the cell membrane a characteristic of cell undergoing

apoptosis?

Short summary of a normal cell that leads to cancer cells

3. Why during the PCR is there a temperature change for certain times and what is the function of these cycles of different temperatures? explain.

• During the PCR, the temperature change for certain times is designed in order to carry out the exponential amplification of the small DNA fragment by chain polymerization.

• Cycles are rendered in a basic three step process which is repeated 25-40 times:

• 1st step: separates the DNA double strand for a period of 15-40 seconds at a temperature of 95º C -97º C.

• 2nd step: designed primers react with the single stranded DNA thus sticking complementary to other bases in a period of 0.5-2min. at a temperature of 40º C- 65º C.

• 3rd step: dNTPs are placed between the primers synthesizing complementary sequence to template DNA strands for a period of 1-2 min. at a temperature of 72º C.

What are the peculiar features of respiratory system of agnathans? 

Sexual reproduction,on the other hand, permits ________ of traits to arise from the contributions of multiple different ancestor