The Rh factor identifies the presence of the rhesus protein in blood. The Rh factor can be represented by a + or – sign. It is important to know the Rh factor because just like how the antigens on the blood must be compatible, the rhesus protein in blood must also be compatible. If a person has Rh+ blood they can receive blood. If a person has Rh- blood they can receiveblood.

After fertilization, which type of cellular division is responsible for the growth and development of a complex, multicellular organism?

Several bird species feed in a certain species of tree. each bird species feeds in a different part of the tree. which statement is true of these bird species? a. they have adapted to different niches due to competition b. they have a carnivorous relationship with the tree species. c. they have adapted to different niches due to predation d. they have a symbiotic relationship with the tree species.

How is the carbon cycle related to global warming ?