<span>Viruses are regarded as being on the borderline of living and non-living because it exhibits characteristics of both living and non-living organisms. Inside a host, the virus can act as a living organism using the host's cellular system while outside the host, the virus crystallizes that makes them incapable of conducting metabolic activities. </span>
Both adenine and thymine are a base pair.
Answer:
True.
Explanation:
The immunoglobulins, MHC ( major histocompatibity complex) and TCR (T cell receptor) plays an important role in the immune system. They protect the individual from the harmful antigens.
The evolution of immune system has done the duplication process. The genes gets duplicated and evolved to perform the specific function. The Immunoglobulin, TCR, and MHC gene evolve by the process of duplication. These genes mainly acts against the specific pathogen and shows the selection according to the primordial antigen receptors.
Thus, the answer is true.
Answer:
they are Na+, K+ and Ca2+ ion channels.
Explanation:
Ionotropic acetylcholine receptors are also called nicotinic acetylcholine receptors because beside acetylcholine (Ch) they respond to nicotine. These receptors are primary receptors in muscle for motor nerve-muscle communication that controls muscle contraction.
Two molecules of ACh are required for receptor to open. Since the receptors are linked to ion channels, the channels open. Opening of the channel allows positively charged ions to move across it: sodium enters the cell and potassium exits.