I believe it's 1. Duplication of DNA has already happens.
Answer:
True
Explanation:
B cells are B lymphocytes and are one of the types of white blood cells. Their main role is in the acquired immune system in which they help in the humoral immune response of the body by the secretion of antibodies. The maturation of the B cells occurs in the bone marrow in mammals. But in birds, these cells mature in an organ named bursa of Fabricius which is a lymphoid organ in birds. These B cells were first isolated form the bursa of Fabricius of the birds.
Answer:
The production of such proteins in these fish is an example of adaptation.
Explanation:
Smooth muscles are the type of muscle that contracts and relax to control the movement of the contents.
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What are Smooth muscles?
Because it lacks sarcomeres and as a result, striations, smooth muscle is an involuntary non-striated muscle (bands or stripes). Its two subgroups are single-unit smooth muscle and multi-unit smooth muscle. A syncytium is the collective contraction of the sheet or bundle of smooth muscle cells that make up a single-unit muscle.
Smooth muscle makes up the walls of hollow organs including the stomach, intestines, bladder, and uterus as well as the blood and lymphatic vessels, as well as the tracts of the respiratory, urinary, and reproductive systems. The ciliary muscle, a type of smooth muscle present in the eyes, changes the shape of the lens by dilation and contraction of the iris.
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Answer:
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