What system are we talking about? Context is needed... water cycle, cells, etc?
Answer:
d. FGF2 signaling, splanchnic mesoderm
Explanation:
Hemangioblasts are the cells that serve as common precursors for blood vessels and blood cells. The hemangioblasts develop from mesenchyme and can give rise to angioblasts (to serve as precursor cells for blood vessels) or pluripotent stem cells to serve as a precursor for blood cells.
The basic fibroblast growth factor (FGF2) is one of the three factors required for initiation of formation of blood vessels. The basic fibroblast growth factor (FGF2) is required for the development of hemangioblasts from the splanchnic mesoderm and their differentiation into angioblasts.
A person who has almost been hit by a falling branch their sympathetic nervous system will be responsible for the heartbeat that speeds up. This may also cause the person decreased motility as they are experiencing a fright. The sympathetic nervous system controls a persons flight or fight response in the body. The correct answer is B.
Known as the Influenza A virus subtype H5N1, or more commonly known as the Avian Flu/Bird Flu, H5N1 is enzootic (maintained within a population) globally in many bird populations. According to recent word from the World Health Organization, as well as the United Nations Food and Agriculture Organization, H5N1 pathogenicity is gradually continuing to rise in endemic areas. However farmed birds are held in check by vaccination, and thus far there is no evidence of sustained human-to-human transmission of the H5N1 virus. The number of worldwide outbreaks being reported are steadily decreasing.
The answer is B Animal cells do not have a cell wall and the shoe box represents the cell wall. Hope this helped!
