reproductive systemS lecture

reproductive systems

produce, store, nourish, and transport gametes

structures of reproductive systems

gonads

ducts

accessory glands

external genitalia

gonads

reproductive organs that produce gametes and hormones

ducts

receive and transport gametes

accessory glands

secrete fluids into ducts

gametes

contain one set of 23 chromosomes (1n) in their nucleus

sperm

ova

spermatozoa are

sperm

produced in male gonads (testes)

ova

production begins in female gonads (ovaries)

• immature form: oocyte

not fully mature until fertilized by sperm

Sperm are produced in

the testes

travel from

testes → epididymis → ductus deference → ejaculatory duct → urethra

accessory glands for males

seminal glands

prostate gland

bulbo-urethral glands

accessory glands in males secrete

products into ejaculatory ducts and urethra

external genitalia for males

scrotum

penis

spermatogenesis

production of sperm

spermatogenesis begins

at puberty and continues until late life (~70 yo)

spermatogenesis results from

series of cell divisions in SEMINIFEROUS TUBULES (in the testes)

spermatogenesis divisions

each division produces a daughter cell that is pushed toward the lumen of the tubule

spermatogenesis involves 3 processes

mitosis

meiosis

spermiogenesis

mitosis for spermatogenesis

stem cells (spermatogonium) [2n] to produce primary spermatocyte [2n]

meiosis for spermatogenesis

meiosis I then II to produce spermatids [1n]

spermiogenesis maturation

spermatids to sperm [1n]

anatomy of a sperm

head

neck

middle piece

tail (flagellum)