1. Reproduction Asexual- Fission- Budding- Fragmentation-
Separation of the original parent into 2 or more
Budding-
New individual splits off from a larger original
Fragmentation-
Breaking of body into several pieces
Advantages of asexual Reproduction:
Very efficient- lots in a short period of time
Perpetuates a successful genotype
Disadvantages:
You know!!!
Loss of variation!!!

2. Sexual Reproduction Bring on the variation! External Fertilization-
Eggs are shed by Female, then fertilized by the male.
AQUATIC
Occurs almost exclusively in a(n) _______________ habitat.
Internal Fertilization-
Sperm is deposited in or near the female reproductive
tract, fertilization then occurs within the female body.
Invertebrate vs Vertebrate:
Invertebrate-
Range from very complex
…to very simple systems without any distinct gonads.
Examples:
Insects have a “spermatheca”
Earthworms are hermaphroditic, but still “copulate”.

3. Sexual Reproduction in Vertebrates:
Some have a common opening for
digestive,
excretory,
and reproductive “products”
Called a cloaca
There is a complex interplay of hormones and
organ responses which regulate reproduction:
Estrous cycles occur in non-primate mammals
If pregnancy does not occur, endometrium gets reabsorbed
Involves pronounced behavioral changes and tends to
follow seasonal and climatic cues.
(cats in heat)
Egg & Sperm production in Humans is quite complex:
Menstrual cycles occur in humans and most primates.

4. The Human Male Testes~ male gonads
Seminiferous tubules~ sperm formation
Leydig cells~ hormone (tesosterone) production
Also called “INTERSTITIAL CELLS”
Scrotum~ outside body temp.
Epididymis~ sperm storage
Vas deferens~ sperm propulsion
Seminal vesicles~ provides 60% of semen fluid. Contains amino acids, fructose, and prostaglandins.
Prostate gland~ anticoagulant; nutrients, alkaline
Bulbourethral glands~ also contains acid neutralizers
Penis/urethra~ semen delivery

5. The Human Female
Ovaries~ female gonads
Follicle~ egg capsule
Corpus luteum~ hormone secretion
Oviduct~ fertilization
Uterus/endometrium~ womb/lining
Cervix/vagina~ sperm receptacle

6. Spermatogenesis Puberty until death! Seminiferous tubules~ location
Primordial germ cell (2N)~ differentiate into….
Spermatogonium (2N)~ sperm precursor
Repeated mitosis into….
Primary spermatocyte (2N)
1st meiotic division
Secondary spermatocyte (1N)
2nd meiotic division
Spermatids (1N)
Sperm cells (1N)
Weblink!

7. Oogenesis Oogonia cells multiply and begin meiosis
Stops in prophase 1 of meiosis = primary oocyte (2n) until puberty
Puberty onward – FSH stimulates follicle to grow and egg cell to complete meiosis I and begin meiosis II = secondary oocyte (n)
Secondary oocyte (n) now in Metaphase II, is released at ovulation, upon sperm entry meiosis II is completed
Weblink!

8. The Menstrual / Ovarian Cycle: Hold on tight!
Menstruation
(endometrium sheds)
GnRH from
Hypothalamus
Corpus Luteum atrophies (if egg not fertilized)
Low
Estrogen/Progesterone
Low LH
Signals pituitary to
Secrete small amounts
of FSH and LH
Stops
Inhibits FSH & LH production
in the pituitary (stops more eggs)
Estrogen also causes
The endometrium to
Thicken.
Signals to Ovary to
stimulate growth of
a follicle.
Corpus Luteum secretes
Progesterone
More estrogen….
More….
MORE….!!
Remains of follicle called
A Corpus Luteum
Follicle secretes Estrogen
which causes increased LH & FSH production
As follicle grows more & more
Estrogen gets produced
LH surge from
Pituitary.
OVULATION!!
NOTE: IF egg is fertilized, embryo secretes
HCG (Human Chorionic Gonadotropin) which
Maintains progesterone/estrogen secretions
From corpus luteum so endometrium is still maintained….
Egg
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