Answer:
d. regulatory; operator; regulatory
Explanation:
In prokaryotes, the regulation of gene expression is done at the transcription level by operons. Examples are the lac operon and the trp operon. To initiate transcription, RNA polymerase and a DNA segment are required for binding called a promoter.
DNA segments that are close to the promoter serve as binding sites for regulatory, activating or repressing proteins. They are called operons.
The Operon is a regulatory sequence close to prokaryotic DNA that lies between the structural genes and the promoter. It is responsible for controlling the transcription of structural genes. When the repressor, encoded by the regulatory gene, binds to the operator, the promoter is blocked which prevents transcription.
The Promoter is located next to an operator and is the site in the DNA molecule that binds to RNA polymerase (which is a regulatory protein) to initiate transcription.
Answer:
A. Buffers absorb excess hydrogen and hydroxide ions to prevent increases or decrease in pH. An example is the bicarbonate system in human body.
Explanation:
In nature, buffer is a known to be a solution capable of maintaining the pH of an ionic solution i.e. resist alteration to the acidic or basic content, by neutralizing excess hydrogen ions (H+) or hydroxyll ions (OH-) added to it.
Buffers, with the aid of their weak acid/conjugate base or weak base/conjugate acid, absorb/react with excess hydrogen and hydroxide ions to prevent increases or decrease in pH. An example of buffer in humans is the bicarbonate buffer system in that maintains stable pH in the human blood.
Answer:
A scientific hypothesis must meet two criteria:
Explanation:
A scientific hypothesis must be testable. A scientific hypothesis must be falsifiable. hope this helps you :) god loves you :)
It's B because during day when temperature of air is increased water retains most of the heat to keep the temperature of atmosphere at tolarable limit. During night when sun sets ocean transfer its heat to atmosphere as heat always transfer from region of high temperature to region of low temperature. In this way temperature of air is stabilized.
Hope it makes sense to you