The pituitary gland secretes follicle stimulating hormone, which acts on the follicles and stimulates them to produce progesterone.
Well, there are four main blood types with two variations of each (so 8 in all):
A+
A-
B+
B-
AB+
AB-
O+
O-
Now, A blood has the presence of the A antigen in it, and so it can't mix with B blood (most of the time).
B blood has the B antigen.
AB has BOTH antigens in it
O has no antigen whatsoever.
So if AB has both antigens, wouldn't it be able to receive antigens from A and/or antigens from B? And same with O, which has no antigens, which has no effect on whatever type of blood it's introduced in (which is why O is considered "the universal donor").
Now, the difference between + & - is simple, and has almost no impact on a person. If a person has +, they have Rh in their blood (it's another type of antigen), and if a person has -, the Rh factor isn't there. So if a person has positive, they have Rh, so more Rh blood can be added to it, and so can blood without the presence of Rh.
Hope this helps!
Depression is the most common mental health diagnosis
Provide sperm to fertilize the eggs in the female reproductive system.
<span>For the first step, you must isolate the cells from the media. The cells contain the DNA so you keep the cells and pellet.
The next step would be a cell lysis which causes the cells to open and the DNA to come out. At this point you would keep the supernatant, as the pellet is the cell membrane and other parts of the cell.
The chelex is to bind to transition metal ions. This would cause and DNases in the cell to become inactive because the metal ion is their cofactor. The pellet in this case would contain the chelex and the DNA would still be in the supernatant.</span>