HSCI 100 Lecture Notes - Lecture 20: Erectile Tissue, Erectile Dysfunction, Glans Penis

• School: Simon Fraser University
• Department: Health Sciences
• Course: HSCI 100
• Professor: Nienke Van Houten

Document Summary

Can be mediated by mechanical stimulation through ans (parasympathetic) release nitric oxide (no) a gas. Also occurs in response to visual, auditory, olfactory mediated by the cerebral cortex. Erection takes place when smooth muscles of the arteries relax thanks to the action of cyclic guanosine monophosphate (cgmp) in cells. The erectile tissue fills with blood and veins get compressed and blood returns slowly, becomes engorged and erect. Erectile dysfunction occurs when the erectile tissue does not expand enough to compress the veins. Viagra blocks the phophodiesterase that breaks down cgmp and thus prolongs erections. Intensely sensitive tip of the penis usually covered by foreskin. Circumcision is the removal of all or part of the foreskin. Each body cells has 46 chromosomes within the nucleus and divide by mitosis only. Cells that have pairs of chromosomes are called diploid. Gametes have only 23 pairs of chromosomes in the nuclei as a result of meiosis. Egg and sperm: differentiated sperm cell products.