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.
Intrasexual selection
Intrasexual Selection is when
members of the same sex within a species contend emulously with each other in
order to acquire chances to mate with others such as the male against male
competition for females. This type of selection often involves posturing and
fighting. Species or individuals suitable for intrasexual selection will possess
developed better weapons than their competitors.
It is further evidence for the theory of plate tectonics.
Hope this helps! :)
A donor offspring is the donation of sperm