true It is a single instance that includes growth,cell wall synthesis and cell expansion
The
Thymocyte progenitors enter the subcapsular region of the thymus as
double-negative cd3- t cells where the double negative refers to lack of
cluster determinants CD4 and CD8. Double-negative cd3- t cells exist as small population
that is 1%-5% of lymphocytes in the lymphoid organs and peripheral blood of
humans and normal rodents.
The plasma membrane of the sea urchin egg has receptor molecules that are specific for binding acrosomal proteins .
<h3>What is plasma membrane ?</h3>
Plasma membrane is the outermost covering of the body which selectively permits the entry and exit of different type of materials .
Thus ,it is also called as selectively permeable membrane.it also separates the inner and outer environment of the cell .
It also helps in the diffusion process .
<h3>What are sea urchins ?</h3>
Sea urchins belongs to the animalia kingdom , Echinodermata Phylum, and Echinoidea class . they are small marine animals .Sea urchins are spiny , globular .
Learn more about sea urchins here :
brainly.com/question/23213828
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