Answer: 2. Each subunit represents a separate polypeptide chain, while one polypeptide chain may contain several domains.
Explanation: Each subunit constitutes of one polypeptide chain. A polypeptide chain has one particular gene coding for it. thus it simply implies that a protein must have one gene for each subunit.
Many proteins is made up of different protein domains. A particular domain may appear in a variety of different proteins.
domains are stable on there own, they can be exchanged via genetic engineering between one protein and another.
During mitosis the cell splits and becomes two
Answer:
The Z lines and H- zone shortens during the muscle contraction.
Explanation:
Sarcomere is the area between the two Z lines. The Z- lines are present in the centre of I - band and H - zone is present in the A - band. The actin filaments which are thin filaments present in I- band and contracts, slide over the myosin filament during contraction.
The I - band, H- zones are became shortens as they are thin than the A- band. It is anisotropic band having thick myosin filaments. They are not flexible and remain in its constant shape during the muscle contraction.
After the muscle contraction, the A- band and the H- zone comes to their original shape. In other words, the sarcomere shortens and comes back during muscle contraction, and relaxation.
<span>The nervous system that controls the voluntary functon of the limbs and the sense organs is called the Autonomic nervous system. The Autonomic nervous system is make up of both, the Parasympathetic nervous system and the Sympathetic nervous system.</span>