The Reproductive System. Functions of the Reproductive System. Survival of the species NOT survival of the individual Unique aspects of reproduction: Not fully functional until after puberty All other body systems are functional at birth Functional stem cells act to produce gametes
Chromosomes isolated during metaphase
Note: each one of these has an exact copy that is on the other side of the cell, but THIS picture shows the “homologous pairs”
Each chromosome you see in the karyotype is only at HALF of this chromatid
Meiosis actually occurs in 2 stages: meiosis I and Meiosis II.
Meiosis I is essentially mitosis (the two daughter cells have 26 PAIRS of chromosomes) since the division involved DNA replication prior to division.
Meiosis II is the classic “meiosis” since the daughter cells further divide their DNA without replicating it.
External homologous structures
Spermatozoa development follows a pathway from the seminiferous tubule – rete testes - epididymis. If not ejaculated, the spermatozoa will remain in the epididymis and be digested (8-10 weeks). If sexually active, spermatozoa will finally mature in the epididymis.
Pay attention to paired vs. unpaired glands that lie along the spermatozoa ejaculatory pathway.
The prostate gland enlarges with age. It is a normal process. Prostate cancer is the second leading cause of death in males. Patient morbidity is not necessarily from the prostate cancer, but the metastasis of the carcinoma that usually enters the spinal cord & brain.
The “dorsal artery/vein” is in reference to “dorsal” on a 4-legged animal rather than the patient being “erect” in anatomical position.
During erection, the parasympathetic nervous system “opens” the gates of the deep arteries within the corpora spongiosum penis in order to allow blood to enter the capillary bed.
Notes: the labia majora have hair & sebaceous glands & are homologous to the male scrotum. The labia minora are hairless & have sebaceous glands.
Pregnant man (due to incomplete