chapter 28 reproductive system part 1

epididymis, vas deferens, ejaculatory ducts, urethra

seminal vesicles, prostate, bulbourethral glands

dartos- smooth muscle tissue, cremaster (skeletal)- descend as an extension of internal oblique muscle through spermatic cord to surround testes

keeps temp 2-3 degrees below core temp

contractions of cremaster muscle moves tested closer to body, contractions of dartos muscle causes scrotum to become tight which reduces heat loss

tunica vaginalis- serous membrane that partially covers testes, tunica albuginea- white fibrous capsule composed of dense irregular CT

lobules- Extends inward, forming septa that divided testis into series of internal compartments, seminiferous tubules- tightly coiled tubules where sperm are produced

spermatogonia, primary spermatocytes, secondary spermatocytes, spermatids, sperm cells

lumen/diploid

support and protect spermatogenic cells, nourish spermatocytes, spermatids, and sperm, phagocytize excess spermatids cytoplasm as development proceeds, produce fluid for sperm transport, regulate effects of testosterone

in spaces between seminiferous tubules and secrete testosterone

process by which seminiferous tubules produce sperm

prophase 1

primary spermatocyte

secondary spermatocyte

secondary spermatocyte start meiosis ll and the products are spermatids

final step of spermatogenesis

starts with maturation of spermatids and the product is spermatozoa

acrosome- vesicle filled with enzymes that help a sperm to penetrate a secondary oocyte to bring about fertilization, nucleus- contains 23 highly condensed chromosomes, middle piece- contains many mitochondria which provide the energy ATP for locomotion, mitochondria- powerhouse of the cell, tail- composed of 4 parts

seminiferous tubules, straight tubules, rete testes, efferent ducts, ductus epididymis, vas deferens, ejaculatory duct, urethra

GnRH- stimulates gonadotrophs in anterior pituitary to increase secretion of two gonadotropins, LH- stimulates the leydig cells in the testes to release testosterone into the bloodstream, FSH- stimulates the Sertoli cells in the testes which support and nourish developing sperm cells, inhibin-a hormone that inhibits FSH

site of sperm maturation, helps to propel sperm into ductus deferens during sexual arousal, store sperm which remain viable here for several months

conveys sperm from epididymis towards prostatic urethra by peristaltic contractions of its muscular tissue

eject sperm and seminal vesicle secretions just before release of semen from urethra

vas deferens, seminal vesicle duct

produce a fluid that makes up a good portion of the semen

alkaline

a milky and slightly acidic fluid that contains citric acid and proteolytic enzymes

25%

secrete alkaline fluid into urethra

seminiferous tubules, seminal vesicles, prostate, bulbourethral glands