The ecosystem requires a constant input of energy because energy cannot be stored. The enrgy always gets converted for supporting life in the ecosystem. Some amount of energy is also lost during this conversion. So if there is not a constant supply of energy, then the ecosystem will ultimately breakdown. In case of humans, the energy is received by consuming food. The energy of the food geets converted to the enrgy that helps a human being to complete his daily chores. So energy is being lost at every step. To regain this energy the humans have to eat food regularly. This way the humans need a constant supply of energy to survive. It is the same in the case of all living things in the ecosystem.
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.
