Are the densities of the planets roughly proportional to their diameters? Use evidence to support your claim.

The male gamete cell is produced in the process called spermatogenesis. The process of spermatogenesis can be broken up into several stages: spermatocytogenesis, spermatidogenesis I and II, spermiogenesis, spermiation.

•the seminiferous tubules- the first stage (spermatocytogenesis) refers to mitotic division of a diploid spermatogonium which produce two diploid intermediate cells called primary spermatocytes. Primary spermatocyte undergoes meiosis I to produce two haploid secondary spermatocytes (adluminal compartment of the seminiferous tubules ). In the phase of spermatidogenesis, haploid spermatids are formed from secondary spermatocytes (meiosis II). During spermiogenesis, the spermatids begin to form a tail and mature under the influence of the testosterone (become motile).  

•Lumen-the mature spermatozoa (haploid male gamete) are released from the protective Sertoli cells of the testes into the lumen of the seminiferous tubule in a process called spermiation.

•the epididymis- The sperm migrate from of the lumen to the epididymis.

•vas deferens-muscular tube

•ampulla-place where the secretions from the seminal vesicle are added

•ejaculatory ducts

•  the urethra.