Answer and Explanation:
Eukaryotic and prokaryotic cells share the presence of:
- cytoplasm, in which their organelles are dispersed.
-the cell membrane, which covers the cell by shaping and regulating the passage of substances (in and out of it).
- ribosomes, are the place where proteins are synthesized.
In addition, both cells possess DNA although this is not the same in both. In the eukaryotic cell it is linear and is within the nucleus, while in the prokaryotic cell it is circular and does not have a true nucleus that protects it.
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:
How Giant Tube Worms Survive at Hydro thermal Vents. In a process called chemo-synthesis, symbiotic bacteria inside the tube worm use hydrogen sulfide spewed from the vents as an energy source for themselves and for the worms.
Explanation: