Answer:
The lactose present prevents the production of lactase
Explanation:
This question is describing a set of genes in bacteria called LAC OPERON. Lac operon controls the production of lactase, which is the enzyme that digests lactose. However, this gene can be regulated at the transcription level i.e caused to be transcribed or not depending on certain factors.
According to the question, lac operon, which regulates the production of enzymes will be transcribed and subsequently translated i.e. turned on when there is a substrate (lactose) that the produced enzyme will work on. However, when there is no need of the lactase enzyme or there is absence of lactose (substrate), the lac operon gene is turned off.
Note that, the statement that "The presence of lactose prevents the production of lactase" is not correct.
Answer:
The correct answer is "excretes; hypotonic; absorbs, hypertonic".
Explanation:
Cell's homeostasis is only conserved in an isotonic solution, since cells that are in an hypertonic solution (high salt concentration) tend to loss water, and in hypotonic solution (low salt concentration) tend to absorb water. Brine shrimp lives in waters that are both, hypertonic and hypotonic and has adapted to overcome this issue by excreting and absorbing salt across its gills. In very high salt concentrations, a brine shrimp "excretes" salt across its gills and maintains an internal salt concentration that is "hypotonic" relative to the water where it lives. In lower salt concentrations, a brine shrimp "absorbs" salt water across its gills and maintains an internal salt concentration that is "hypertonic" relative to the water where it lives.
Answer:
The correct answer will be option-A
Explanation:
Emotional memory refers to the memories of experiences which evokes or triggers the emotional reaction in higher organisms.
Emotional memory after evoking the emotional reactions remembers the past experiences based on which the person feels if the present event is pleasant or unpleasant.
The pounding of the heart is caused by the shock or the stress conditions observed with the fast beating of the heart. In the given question, When the heart pounds after seeing the rattlesnake will be considered response caused by the emotional memory as the rattlesnake is dangerous to humans based on the past experiences which evoke the emotional response.
Thus, option-A is the correct answer.