300 BC by Greek philosophers
Answer:
) Presence of specific glycoproteins on the cell membrane
Explanation:
When specif glycoproteins(antigens) or antibody are present on a cell membrane of Red blood cell,they can be used to identify the blood type.Antigens are substances capable of triggering an immune response in a cells.
In addition,they function in transport of molecules across the RBC. They help in the maintenance of the RBC,and aiding the arrest of cells capable of causing diseases to the body.
Therefore,they are good determinants of blood types,based on this two types of antigens present in a blood type.
These two antigens used for classification of blood types are the 1-the ABO antigens 2,the Rhesus antigens.
Essentially,when a WBC produces an antibody ,which is a molecule that defends the body,If this is not compatible,the antibody will recognize it as a foreign body and attack it.Thus such blood types are not compatible. Thus the antibody-antigen reaction are good for knowing and classify blood types.
Antigen can also be glycoprotein,carbohydrate or glycolipids.
Generally blood types are inherited from both parents.Therefore the antigen present on the RBC are combination of the alleles from each parent.
Answer:
How is the endocrine system related to the nervous system in terms of its regulatory activity?
For one, the endocrine system uses chemical signaling (hormones, produced by glands) while the nervous system uses electrical signaling (neural impulses). The signal transmission of the nervous system is fast because neurons are interconnected, but the functions are more short-lived.
Explanation:
Answer:
Hilum.
Explanation:
Hilum may be defined as the type of the depression or the fissure and may present in kidney known as kidney hilum, present on spleen and the lungs. This is also known as hilus.
The hilum marks the entry and exit of the nerves and the blood vessels. The lung hilum is a triangular like depression through which the blood vessels, capillaries and the nerves enter and leave in the lungs and connects the other organ of the body.
Thus, the correct answer is option (d).