The Male Reproductive System:

Male gametes, or sperm, are made through ​ (a)   . This process, called ​ (b)   , takes place in the ​ (c)   . The testes in a sexually active male make more than 200 million sperm cells ​ (d)   .

The testes, also called ​ (a)   , are the organs that produce ​ (b)   in males. The testes also produce the male sex hormone ​ (c)   , which is responsible for such male characteristics as ​ (d)   and low voice.

Once a human male is sexually mature, ​ (a)   begins and continues for the duration of the male’s life. Inside the testes, the original ​ (b)   (2n)cells that begin meiosis are called ​ (c)   . Diploid cells have ​ (d)   of chromosomes. They are found in tissue called ​ (e)   highly coiled tubes inside the testes , which is where the sperm is produced.

Once they begin ​ (a)   (which reduces the number of chromosomes to half), they create four ​ (b)   sperm cells that are stored until they are needed. Haploid cells have only ​ (c)   set of chromosomes.