Transcription factors are necessary for an initiation of transcription at a regulated gene but not sufficient.
Transcription is the first step of gene expression in which DNA molecule is copied (transcribed) into RNA (mRNA) by RNA polymerase. The process of transcription is divided into three phases:
1. Initiation
• RNA polymerase with transcriptional factors bind to gene promoter Transcription factors can enhance the interaction between RNA polymerase and a DNA sequence- promoter, encouraging the expression of the gene. Such transcription factors are called activators. Otherwise, when the gene expression is inhibited, factors are called repressors and they bind to sequence –operator.
• RNA polymerase unwinds DNA double helix (transcription bubble is formed)
2. Elongation
• RNA polymerases adds nucleotides complementary to DNA
3. Termination
• RNA polymerase gets to stop codon (transcribes a sequence of DNA known as a terminator)
• Formed complementary RNA strand is released from DNA-RNA complex
Answer:
The correct option is <u>B. Lipids</u>
Explanation:
Lipids can be described as molecules which dissolve in non-polar solvents and cannot dissolve in water. The biological function of a lipid molecule is to store energy as well as to structure the shape of cell membranes. Lipids are also used in a cell for signalling.
Lipids are made up of carbon, hydrogen and oxygen. Some lipids might have phosphorus in them like the phospholipids which make up the cell membrane.
Answer:
D
Explanation:
Bone marrow contains stems cells which then turn into immature blood cells and they mature there. kinda like a school for young blood cells. they also make white blood cells and platelets.
<span>The correct answer is the source of segregation.
Source of segregation of a complex acoustic signal into separate auditory events. Some sounds which come from different sources, they can be localized by the human brain to where the sound is coming from.
Based on loud of the sound it will be easy for a person to detect where the sound is coming from.</span>
I got two, but I could be wrong.
