Answer:
Decreased transcription of structural genes of try operon irrespective of presence or absence of tryptophan. The leader sequence has a tryptophan codon in its sequence 1 that does not allow the formation of attenuator structure when tryptophan levels are low.
Explanation:
The leader peptide has a tryptophan codon in sequence 1. When tryptophan levels are low, translation of sequence 1 pauses at the tryptophan codon and the sequences 2 and 3 pair with each other. This does not allow pairing of sequences 3 and 4 and the formation of the attenuator is inhibited. Therefore, tryptophan operon is expressed when tryptophan levels are low.
When the leader peptide sequence is replaced with the one from phenylalanine operon, expression of tryptophan operon will be reduced. The replaced sequence lacks a tryptophan codon and therefore, the translation would not pause when the tryptophan levels are low. This would allow the ribosome to quickly translate the sequence 2. Sequences 3 and 4 will pair to form attenuator and the gene expression will be reduced irrespective of low levels of tryptophan.
The question is incomplete as it does not have the options which are:
By binding to a plasma membrane receptor it initiates a cascade.
It relays a signal from the cytoplasm to the plasma membrane.
It activates relay proteins.
By binding to DNA it triggers the transcription of a specific gene.
It is a plasma membrane protein that binds signal molecules.
Answer:
By binding to DNA it triggers the transcription of a specific gene
Explanation:
The transcription factors are the protein molecules that bind with a specific sequence of the DNA. These transcription factors after binding to DNA initiates the process of transcription thus act in gene expression.
The transcription factors are involved in the long transduction pathway which has to act on the DNA sequence and produce the enzymes like involved in the synthesis of steroid hormones in the body.
Thus, the selected option is correct.
Answer:
Its A.
Explanation:
Correct on gradpoint my dooods!
Answer:
The answer would be A. Earthworms burrowing in the ground
Vitamin C depending on a stuffy nose, it can help by breathing and cold flu, but it’s nice to take daily vitamins