Answer: c. Transition Reaction
Explanation:
During the transition reaction, Acetyl-CoA is formed and connects the first stage of glycolysis with the Krebs Cycle (Citric Acid Cycle). In the presence of oxygen, pyruvate enters the mitochondria and is oxidized to form a compound of 2 carbon, acetate, with energy and CO2 release. During this process, the acetate binds to a coenzyme(coenzyme A (CoA)) - forming the acetyl-coenzyme A.
The 3 steps:
1. pyruvate is oxidized and forms acetate with liberation of CO2;
2. the energy released in the oxidation of pyruvate is stored in the reduction reaction of NAD+ to NADH + H+
3. The acetate molecule combines with coenzyme A to form acetyl-coenzyme A.
When the fertilized egg implants somewhere outside the uterus is called ectopic pregnancy
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Albert, a student researcher, varies the amount of food given to rats in an experiment to measure the effect on their learning behavior. In albert's study, the amount of food given is the independent variable.
An independent variable is under the control of the experimenter. Independent variable does not depend on the other variables involved in the experiment. Since the amount of food is varied, it is not depending on other variables like size of mice, weight, etc.
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.
Digestion occurs in the stomach and the duodenum through the action of three main enzymes: pepsin, secreted by the stomach, and trypsin and chymotrypsin, secreted by the pancreas.During carbohydrate digestion the bonds between glucose molecules are broken by salivary and pancreatic amylase.The digestion of certain fats begins in the mouth, where short-chain lipids break down into diglycerides because of lingual lipase. The fat present in the small intestine stimulates the release of lipase from the pancreas, and bile from the liver enables the breakdown of fats into fatty acids.DNA and RNA are broken down into mononucleotides by the nucleases deoxyribonuclease and ribonuclease (DNase and RNase) that are released by the pancreas.
