Answer:
Pleiotropy
Explanation:
Pleiotropy is a genetic condition in which a single gene conditions the expression of multiple phenotype. There are different types of pleiotropy depending on the underlining mechanism
- <em>gene pleiotropy</em>
- <em>developmental pleiotropy</em>
- <em>selectional pleiotropy</em>
- <em>antagonistic pleiotropy </em>
<em>Phenylketonuria is a disease characterized by increased level of amino acid phenylalanine in the blood. It caused by mutation to the gene responsible for breaking down phenylalanine in the blood. Elevated level of phenylalanine causes other issues such as mental problems, urine coloration and reduction in skin pigmentation. This is a clear case of pleiotropy.</em>
Answer:
Examples:
- Short-term adaptation: feedback inhibition
- Long-term adaptation: regulation of gene expression
Explanation:
Feedback inhibition is a mechanism where the product of a chemical reaction is utilized to modulate its own subsequent synthesis. In bacteria, feedback inhibition allows regulating different metabolic pathways in response to environmental conditions by modulating enzyme activity through enzyme reaction products. Moreover, bacteria may also respond to environmental inputs by long-term changes in gene expression. For example, bacteria contain transcription factors activated during stress, which are able to activate the transcription of particular genes into messenger RNAs (mRNAs) that would subsequently be used to generate particular enzymes by the process of translation. These transcription factors may bind to specific DNA motifs in order to promote transcriptional activity, thereby regulating the production of the corresponding enzyme.
C is the answer to your problem
Answer:
B. Proteins
Explanation:
Salivary amylase is an enzyme that starts the breakdown of starch in the mouth. Gastric glands of the stomach secrete gastric juice, which contains HCl to kill bacteria and denatures proteins, intrinsic factors, and the enzyme pepsin. The chief cells of gastric glands secrete pepsinogen (an inactive form of pepsin).
Pepsin begins the digestion of proteins in the stomach. It breaks down certain peptide bonds between amino acids and thereby, breaks down protein chain into smaller peptide fragments. Pepsin requires a very acidic environment of the stomach (pH 2) and becomes inactive at a higher pH.