Lecture 1 Flashcards
The meaning of life
Sex and Reproduction are not the same thing!
Humans are the only animal (that we know of) that
has learned that sex leads to reproduction
has determined how to separate the two
Purpose of Reproduction
Generation of new individuals.
Continuation of the species.
Pass on chromosomes to new individuals
Chromosomes (genes)
carry the “blueprint” for making that individual
copies of all chromosomes are carried in every cell of the body (except gametes)
Purpose of Sexual Reproduction
Provide new combinations of versions of genes on chromosomes in offspring.
Mechanism of preservation of gene versions.
Diversity of individuals within the species.
Mechanism of natural selection = passing on of advantageous traits to offspring.
Difference between Sex, Reproduction and Development
Sex - The act of using biological structures and behavior to generate and carry male and female gametes to a site where they can join.
Reproduction – The joining of male and female gametes to form a zygote.
Development – The differentiation and growth of an individual from zygote to death. (we are not covering this aspect)
Male - Function
Make sperm
House sperm until ejaculation
Contribute important fluids and chemicals to semen
Transport sperm and associated fluids to female
Male Structures
Scrotum (2)
Testis
Seminiferous tubules
Epididymis
Vas (ductus) deferens (2)
Glands
Bulbourethral (Cowper’s) (2)
Seminal vesicles (2)
Prostate (1)
Ejaculatory duct
Penis (1)
Urethra
Important Tissues
Epithelium: surface tissue
protects
regulates passage of substances across surface
Smooth muscle: involuntary muscle
Connective tissue: support tissue
Gonads and Gametes
Gonads
Testes and Ovaries
Gametes
Sperm and Ova
Testes (2)
Function: produce sperm produce hormones steroid hormones (e.g. testosterone) inhibin
Testis
Seminiferous Tubules
where sperm are produced
Testis Interstitial
where androgens (e.g. testosterone) are produced
Epididymis
Where sperm mature and are stored in anticipation of ejaculation
Vas Deferens
Ejaculatory Duct
Glands secrete ingredients of semen
Bulbourethral Lubricating mucus Urine neutralizer Seminal Vesicles Lots of fluid Mucus and protein Fructose (sperm nutrient) Citric acid (Vit C) Prostaglandins Prostate Neutralizer for acids of vagina Clotting enzyme Antibiotic (prostate specific antigen) – prevent tract infections Zinc – stabilizes sperm
