You have been dispatched to a residence where a woman lacerated her arm after falling while holding a drinking glass. She inform
s you that when she was first cut, blood spurted from the wound, and then within a second or two, it subsided to a mere trickle. She asks why this would happen. Which one of the following is the correct response? A) "Blood has the ability to clot within a second or two of injury."
B) "Blood vessels tend to constrict quickly once they are injured."
C) "Red blood cells will quickly repair the injury to the blood vessel."
D) "The skin around the injured blood vessels quickly swells and stops bleeding."
According to the details given in the example, because she cut a blood vessel, the blood vessel, using the muscles along the walls of the vessel, constricted as quickly as possible once it was cut to be able to stop the bleeding. So the answer is option B.
In oxygenic photosynthesis, the first electron donor is water, creating oxygen as a waste product. In anoxygenic photosynthesis various electron donors are used. Cytochrome b6f and ATP synthase work together to create ATP. This process is called photophosphorylation, which occurs in two different ways.
