Reproductive System Flashcards
Mitosis vs Meiosis
Mitosis:
- Creates identical diploid daughter cells of parent cell.
Meiosis:
- Chromosomes do not duplicate before daughter cells divide.
- Half of total chrom. go to each daughter cell (haploid).
- At random which chrom. go to which daughter cell.
Spermatogenesis: What is it? What is the process?
- Production of male sex cells.
Process:
1. Primary spermatocyte divides by meiosis into secondary spermatocytes.
2. Secondary spermatocytes divide by mitosis into four spermatids.
3. Spermatids grow tails & physical changes making them spermatozoa (half are X, half are Y).
4. When fully developed, they detach & carried to epididymis for storage then ejaculation.
Oogenesis: What is it? What is the process?
- Production of female sex cells.
Process:
1. Primary oocyte divides by meiosis into large secondary oocyte & small “polar body”
(Each has the haploid chrom. #)
2. Secondary oocyte & polar body divide by mitosis into an ovum and three polar bodies.
3. Three polar bodies will not develop, ovum will.
Spermatozoa structure (4)
- Acrosome: contains digestive enzymes to help reach & penetrate ovum.
- Head: contains nucleus of cell.
- Neck “midpiece”: large concentration of mitochondria in a spiral form.
- Tail: muscle like contractile fibrils. Produces whiplike movement (locomotion) to propel forward.
Components of male reproductive system (2)
- Penis
- Testes
Testes structure and function
Function:
- Produce sperm and hormones.
Structure:
- Outside abdomen in inguinal region.
- Housed in skin sac; scrotum.
Penis function
- Erection: parasympathetic reflex trig by sexual stim.
- Involves olfactory cues & behavioral changes.
- Arteries dilate, increase blood flow to penis. - Ejaculation: reflex impulse of semen.
- Semen moves from accessory repro glands into pelvic portion of urethra.
- Rhythmic contractions of urethra pump semen out & into female repro tract.
Penis structure (6)
- Roots: bands of connective tissue (crura) that attach penis to the brim of the pelvis.
- Body: two bundles of erectile tissue (corpus cavernosum urethrae & corpus cavernosum penis).
- Glans: distal end; numerus sensory nerves.
- Prepuce: sheath of skin that encloses the penis when flaccid.
- Os penis: bone in the penis; urethra run thru groove on ventral side.
- Bulb of glans: enlargement towards rear of the glans. Engorges w/blood, “ties” w/muscle contractions, & subsides 15-20min.
Components of female reproductive system (7)
- Ligaments
- Ovaries
- Oviducts
- Uterus
- Cervix
- Vagina
- Vulva
Ligaments (3) of female repro system
- Broad lig: sheets of peritoneum.
- Suspends ovaries, oviducts, & uterus.
- Contains blood vessels & nerves. - Suspensory lig of the ovary. Ovarian end of broad lig attached to body wall in area of last rib.
- Round lig of the uterus. Fibrous tissue & smooth muscle in lateral fold of the broad lig on each side.
Ovaries function and structure
Structure:
- In dorsal abdomen near kidneys.
- Appearance varies by species.
Function:
- Site of oogenesis.
- Production of estrogens & progestins.
- Ovarian cycle, ovulation, corpus luteum.
Ovarian cycle events (5) and what it’s influenced by (2)
- Influence: Follicle stim hormone & luteinizing hormone (granulosa cell produces these).
Events:
1. Primordial follicle (primary): this is an immature oocyte surrounded by single layer of follicular cells.
2. Follicular activation (growth is triggered). - Follicular cell thicken & mult. into layers: granulosa cells. Follicle grows as granulosa cells mult.
3. Granulosa cells produce increasing amounts of estrogens as follicle becomes larger.
4. Fluid-filled spaces form between granulosa cells. Spaces gradually merge into one large fluid-filled space: the antrum.
5. Mature follicle: production of estrogens peaks.
Ovulation
(sort of a cont off of ovarian cycle)
A mature follicle ruptures with the release of reproductive cell into the oviduct. Now called ovum.
- The rupture causes the release of fluid from the antrum along with ovum.
- Empty follicle fills w/blood: corpus hemorrhagicum.
Corpus Luteum formation and function
Formation:
- Granulosa cells mult. in the corpus hemorrhagicum and form a solid (corpus luteum).
- Influenced by LH continuous stim.
Function:
- Produces progestins. Necessary to maintain a pregnancy!
- Endocrine signal to ovary causes corpus L to be maintained if ovum implants in uterus.
Oviducts
AKA “fallopian tube” & “uterine tubes”
- Muscle contractions & cilia movements guide ovum toward the uterus.
- Usual site of fertilization (NOT in the uterus).
