AP Biology – Animal Reproduction 1/12General Points
Two major modes:
Animals – Many reproductive cycles, patterns and options …
Example: parthogenesis
What if you rarely encounter a member of the opposite sex?
Human Reproductive System – Need to know all the structures and functions … Let’s label ‘em up first!
AP Biology – Animal Reproduction 2/12
Structure and FunctionTestes (male gonads) -Produce _____________
-Produce ___________________________
-Found in a sac called the ___________________
-Suspended outside of the body cavity for ___________________
-Testes wall made of fibrous connective tissue (Divides the testes into lobules (chambers))
-Inside chambers are long tubes (70 cm - called the _______________)
This is the actual site for ____________________________.
-Interstitial cells secretes androgen “_____________________”
_______________________________ –Sperm Development
Sperms cells are derived from undifferentiated cells called __________________________________ (sing. Spermatogonium), which lie just on the outside wall of a tubule and divide _______________________, always producing new _____________________________.
Some newly formed spermatogonia move away from the outer wall to increase in size and become primary _______________________________, which undergo ____________, a type of cell division.
Primary spermatocytes, with _________ chromosomes, divide to give 2 __________________ ______________________, each with _________ chromosomes.
Secondary spermatocytes divide to produce _____________________, also with _____ chromosomes.
Spermatids then differentiate into sperm (________________________)
Also present in the tubules are the ________________________, which support, nourish and regulate the spermatogenic cells.
AP Biology – Animal Reproduction 3/12 Epididymus -____________________________________
Seminal Vesicle -________________________________
Cowper’s Gland -Pea-sized organs that lie posterior to the prostate on either side of the urethra.
- ____________________________________
Prostate Gland -A single dough-nut shaped gland that surrounds the upper portion of the urethra just below the bladder.-Older men can have their prostate become enlarged and urination becomes quite painful. (surgically fixed)
-_____________________________________________
Urethra -__________________________________________________________________________
Ductus Vas Deferens -________________________________________________________________
Penis -_____________________________________________________________________________
Path of Sperm
1. Formed in the __________________________________
2. Mature and stored in the ____________________________________
3. Stored in the ________________________________
4. Enters the _______________________________ just prior to ejaculation
5. Accessory glands (prostate, Cowper’s gland, and seminal vesicle) and ______________________.
6. Semen and sperm exit through the penis.
Seminal Fluid
SOURCES: 1. _________________________
2. _____________________________
3. ______________________________
FUNCTION: Produce slightly basic pH
1. 7.5 preferred pH of sperm (Basic) to ________________________________
2. Provides _____________________________________ for sperm
3. Contains ______________________ – chemicals which cause the _____________
4. Aids in the ____________________________________ to the egg.
5. ______________________________
Sperm Parts
Head: 23 chromosomes
________ attached - type of ______________________________
-attached to nucleus
-contains _____________________________
AP Biology – Animal Reproduction 4/12-digests a ______________________________ so sperm can penetrate.
Middle Piece: Contains __________________________________
Tail: ______________________________________________
Function of Testosterone (Male Sex Hormone)
1. Essential for development of
______________________________.
2. Essential for the development of ______________________
-spermatogenic cells take up _____________________ which stimulate their activity.
3. Increased testosterone concentration at puberty causes ______________________________.
4. Secondary Sex Characteristics
-facial hair -larynx expands (voice changes)
-_________________ -Increase muscular strength
-pubic hair -______________________
-oil and sweat glands secrete(=Stinky) -sex drive
Hormonal Control of Testosterone
-Hypothalamus releases GnRH (____________________________________________)
-GnRH causes anterior pituitary to release 2 gonadotropic hormones:
FSH (___________________________________________)
-promotes spermatogenesis in the seminiferous tubules
LH (__________________________________)
-promotes production of testosterone in interstitial cells.
NEGATIVE FEEDBACK
Increased testosterone concentration in the blood causes the _____________________________ to make
_____________________________, therefore __________testosterone is produced. Decreased testosterone concentration
in the blood causes the __________________________ to make more LH and therefore more testosterone is produced.
Increased concentration of stored sperm causes an increase in production of_________________ and decreases
production of FSH, therefore production of sperm _________________. Decreased concentration of stored sperm causes
a _____________________________________ and more FSH, therefore ___________________________ is produced.
AP Biology – Animal Reproduction 5/12
Female Reproductive System
Ovaries -Produce _________________________
Uterus (Womb)-________________________________
Oviduct -conducts __________towards the _________
- also called the _________________ or
uterine tube
Fimbriae -finger-like projections of the _________
________________________________.
-along with cilia in the oviducts, they cause a
______________which sweeps the egg
______________________________
Cervix -narrow end of _____________________
-dilates _______________ to allow baby
to exit
Vagina -Receives penis during sexual intercourse and serves as a ______________________
Clitoris -female _______________________; homologous to the male penis
-provides sensitivity during intercourse
Labia major and Labia minor - _______________________________________________which surround and protect the
clitoris and the openings of the vagina and urethra.
Functions of Estrogen ( __________________)
1. Stimulates growth of _________________________________________
2. Egg maturation
3. Secondary Sex Characteristics
-armpit hair / pubic hair
-______________________________________________
-enlarged _________________________________ (wider hips)
-breast development (requires ____________________________as well)
Ovarian Cycles
Day 1 –13 Follicular Phase
1. Hypothalamus produces a GnRH to stimulate _________________________________
2. FSH and LH stimulates ______________________________________ from pituitary gland
3. Primary follicle (46 chromosomes) contains primary ___________________________ which divides.
(produces ___________________________________)
4. One oocyte gets most ______________________________________. (called a secondary
oocyte, which is inside the now secondary follicle)
4. Other oocyte called the _____________________________ disintegrates
AP Biology – Animal Reproduction 6/125. The secondary follicle grows into a ______________________ (vesicular) Follicle.
Day 14 Ovulation
6. Grafian Follicle ________________ (ovulation) LH is at its highest and triggers ovulation
Day 15 –28 Luteal Phase
7. The follicle has lost its oocyte (or “egg”) and forms into the _______________________
(_________________________________________________.)
-the corpus luteum _______________________________
-___________________________________________
If pregnancy (fertilization) does not occur: ________________________ breaks down (about 10 days). Cycle will repeat.
If pregnancy does occur: Corpus luteum remains for 3 – 6 months and continues to produce ___________________.
Uterine Cycle
Day 1 –5 Menstruation
1. Low levels of sex hormones (_______________________________ has just disintegrated)
2. _____________________________ (lining of Uterus) breaks down
3. Cells of the endometrium, blood vessels, and blood are ___________________ and exit the vagina.
4. A flow of blood (___________________________) passes out of the vagina during a period called
AP Biology – Animal Reproduction 7/12 ____________________________.
Day 6 – 13 Proliferative phase
1. Increase _________________by the ovarian follicle causes the ____________________ to rebuild.
2. Endometrium becomes thick and ___________________________
Day 14
________________________________ (release of the egg)
Day 15 –28 Secretory Phase
1. Increase level of progesterone by the _____________________
2. Endometrium doubles in thickness
3. Glands produce _______________________
4. Now prepared to receive embryo
If no pregnancy. The ________________________________________, decrease in progesterone production occurs and
the ___________________________________. Cycle continues.
Controls of Cycles by Hormones
Hypothalamus secretes GnRH (_______________
____________________________) and causes the
anterior pituitary to secrete ____ and __________
FSH causes ______________________________
__________________________. Maturing
follicles produce _______________.
Increase in estrogen concentration causes the
______________________________________
AP Biology – Animal Reproduction 8/12
Around day 12, the increased levels of estrogen
suddenly cause __________________________
on the anterior pituitary and stimulates the release
of FSH and ______________________________.
This surge of LH ________________________.
LH then triggers the remaining follicle cells to
differentiate into the corpus luteum which secretes
progesterone and some estrogen.
Estrogen promotes the _____________________________________________
Progesterone stimulates the endometrium to
_________________________________
These changes are to prepare for the possibility of
________________________________________
At the end of the cycle, if the egg has not been fertilized or implantation and pregnancy do not occur,
________________________________________________ stops releasing estrogen and progesterone.
Without these hormones, the _________________________________________________ breaks down and
_______________________________ starts.
Implantation
Fertilization (___________________________________________________________) occurs in the
______________________. The joining of the two cells forms an _________________
Implantation of the embryo occurs in the ____________________. Embryo embeds itself in the
___________________________ several days after fertilization. _______________________ has now begun.
AP Biology – Animal Reproduction 9/12
Implantation starts the production of the hormone ____________________________________________
_________________________which prevents the corpus luteum from degenerating.
It is found immediately in blood and a few days later in the urine. Ex. pregnancy test. (About one week later)
HCG prevents the breakdown of the ___________________________________. The Corpus Luteum produces
progesterone that keeps the __________________________________from breaking down.
FSH and LH is being produced which ___________________________________________________.
The ______________________ begins to develop from embryonic and maternal tissues after implantation.
Placenta
Contains both ________________________________________________________
Area where __________________________________________________________.
No exchange of ____________________________________
Diffusion of gases and wastes and nutrients occur over the ______________________
Placenta produces HCG, progesterone (prevents breakdown of the endometrium) and estrogen
(___________________________________________________________)
Oxytocin and Positve Feedback
Oxytocin used to __________________________. Oxytocin causes uterine contractions, which in turn stimulate the
release of more oxytocin. Positive feedback
Oxytocin also causes _______________________________________. Lobules containing milk contract forcing milk
into ducts which lead to the nipple.
AP Biology – Animal Reproduction 10/12
Contraception
AP Biology – Animal Reproduction 11/12
Cloning
Various techniques have been developed to _________
Stem Cells
Stem cells are __________________________________
AP Biology – Animal Reproduction 12/12
Whew … some really complicated things happening here! … and we didn’t even look at plants!!!
Understanding the uterine and ovarian cycles is probably the hardest part. Try to organize your thoughts into structures that are involved, hormones and what they do, timing of different events (and why), then focus on the interplay between all these items. Finally, draw a diagram which includes all these items with the correct timing. Good luck!
Structures Hormones Events
