Answer:
400
Explanation:
Because if you pull one black marble out of four and there are 100 black marbles then there is 300 others, so in total it would be 400 marbles.
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The answer is the first one
Answer:by being produced in the testes outside the body
Explanation: spermatogenesis is the production of male gamates,the sperm.this process occurs in the seminiferous tubules in the testes.epithelial cells produces the primary spermatocyte which divides to give a secondary spermatocyte.
The secondary spermatocyte divides to form spermatids,which differentiates to form the spermatozoons.
Testis is housed in the scrotal sac.
Sperm production is sensitive to temperature. Too high temperature can cause formation of abnormal cells . As a result the scrotal sac is located outside the body
Answer: The nervous system of human body is responsible for thermoregulation.
Explanation:
Thermoregulation is the process whereby an organism maintain its internal temperature despite changes in External temperature. The nervous system of human body is responsible for thermo regulation. The nervous system consist of nerves cells and fibres which send nerves impulses to the body parts. It comprises of central nervous system and peripheral nervous system. The centsl nervous system consist of brain and spinal cord while the peripheral nervous system consist of nerves. A part of the brain (central nervous system)called hypothalamus controls thermo regulation. When it senses a change in internal temperature of the body, its send signals to the organs, muscles, glands and nervous system , they respond differently so as to restore the body temperature to its normal one.
These ions bind to troponin, which forms a complex with tropomyosin. The process is called <span>Excitation-Contraction Coupling 3.</span>
It includes series of events, beginning with the production of an electrical impulse (action potential)<span> and ending with </span>contraction<span> of </span>muscles <span>in the </span>heart.