Scientists cannot provide accurate information on environmental conditions
Answer:
The hair is made up of 95% keratin, a fibrous, helicoidal protein (shaped like a helix) that forms part of the skin and all its appendages (body hair, nails, etc.). Keratin is synthesized by keratinocytes and is insoluble in water, thus ensuring impermeability and protection for the hair.
Explanation:
Rachel Carson played a key role in the birth of environmentalism in the 20th century.
She became increasingly aware of the harmful facts of insecticide DDT on the environment. This compelled her to write her most famous work Silent Spring and defending herself against attacks from commercial interests.
The book also played an influential part in persuading governments to ban or heavily restrict the use of DDT and similar chemicals that persist in the environment.
Sertoli cells are stimulated by <u>FSH</u>, while leydig cells are stimulated by<u> LH.</u>
<h3>Sertoli and Leydig Cells:</h3>
The creation of T is stimulated by LH in Leydig cells, while the production of regulatory molecules and the nutrients required for maintaining spermatogenesis are stimulated by FSH in Sertoli cells in concert with T. As a result, Sertoli cells indirectly control spermatogenesis via T and FSH.
The growth and maintenance of the male reproductive system and spermatogenesis depend on LH-stimulated Leydig cell androgen synthesis. The interstitial cells of Leydig, which are concentrated heavily in the testis of newborn boys and adult males following puberty, release testosterone. Interstitial cells are another name for Leydig cells. The interstitial spaces outside of seminiferous tubules are where they can be found.
Learn more about Sertoli and Leydig cells here:
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