Answer:
The correct option is d) head.
Explanation:
Bicoid protein works as a transcription factor. It enters the nuclei of the embryos in early segmentation, where it activates the hunchback gene. In Drosophila, embryonic development begins at the time of fertilization. The sperm enters the mature oocyte through the micropile, a structure located in what will be the anterior region of the egg. Bicoid and hunchback mRNAs, protein products are critical for the formation of the head and thorax. Already in the early stages of oocyte development, certain mRNAs are located in specific regions of the oocyte: mRNA molecules encoding the Bicoid protein are preferentially located in the anterior region of the oocyte. Moderate levels of the bicoid protein are necessary to activate the formation of the thorax (i.e., the expression of the hunchback gene) but the formation of the head requires high concentrations of Bicoid, the promoters of a specific gap gene of the head must have sites of low affinity binding for Bicoid, so that this gene can be activated only in extremely high concentrations of Bicoid.
The lack of Bicoid protein affects the formation of the head and other structures in the anterior region of the oocyte.
Answer:
What grade for this is it
When two protein chains combine to form an active protein, the structural level is quaternary.
<h3>What is a quaternary structure?</h3>
The quaternary and tertiary structure of a protein is the tridimensional shape of the protein, which involves protein domains.
The quaternary protein structure refers to the different arrangements generated by different protein subunits.
The primary structure of a protein involves its amino acid sequence, whereas the second structure involves protein chains.
Learn more about quaternary structure here:
brainly.com/question/5286438
ATP consists of three phosphates, a base (adenine) and a sugar (ribose).