Sexual Reproduction

Question 1

Sexual Reproduction

Answer 1

2 haploid gametes come together and form a diploid zygote
Males: Spermatozoa
Females: do not make gamete cells, make a gamete nucleus (potential gamete every 28 days)

Question 2

Reproductive Organs

Answer 2

Males: testes make gametes
Females: ovary make potential gamete nuclei

Question 3

Reproductive Steroids

Answer 3

Male: testosterone and dihydrotestosterone
Female: Estrogen, progesterone

Question 4

Male Spermatogenesis

Answer 4

Negative feedback (constant) 
Cells: spermatogenic cells, accessory cells; leydig (converts cholesterol into T) sertol (converts T into dHT) 
spermatogenesis takes place in the seminiferous tubules in the testes `\

Question 5

Ejaculatory Duct

Answer 5

Seminal vesicle, prostate gland, bulbouretheral gland
all together provide nutrients, sugar, enzymes, ions, etc.
goes into the urethra and the urinary tract
through nerve reflex ejaculation releases 100- 300 x 10^6

Question 6

Female Reproduction

Answer 6

oogenesis
make ovum nucleus
unequal cytokinesis in which most of the cytoplasm ends up on single daughter cell
process takes place in follicles of the ovary (oogenic cells)
Accessory Cells: theca cells to convert cholesterol into T; Granulosa cells convert T into E (enzyme aromatase)

Question 7

Follicle Development

Answer 7

In ovary: many follicles (primary oocytes) start maturing but only one of them wins
Primary oocyte is covered by granulosa cels and defined membrane around it (zona pellucida) around the granulosa cells are theca cells
Combination of E, LH and FsH has proliferation of cells
built up of fluid pushes out the primary oocyte (secondary oocyte comes out of ovary) inside corpus luteum is left in ovary (estrogen and progesterone inside)

Question 8

Corticol Reaction

Answer 8

Granules move up into the membrane and after change the structure to prevent polyspermy
Secondary oocyte goes through meiotic division and the polar body which gets kicked out
Ovum nucleus and spermatozoa nucleus break down and the DNA recombines and new nucleus is formed (get zygote 46/2C)

Question 9

hCG

Answer 9

Basis for pregnancy test and basis for morning sickness
extra when there are twins
only around during first trimester
maintains the corpus luteum

Question 10

Twins

Answer 10

Fraternal: two distinct fertilization (2 zygotes); more than one oocyte is use, genetically like siblings
Identical Twins: one fertilization (1 zygote); cells during cleavage separate; most split after the 2 cell stage

Question 11

Placenta

Answer 11

Extremely important for hormone production

hCG keeps corpus luteum in tact (creates E+P and creates prolactin which helps with the production of mammary glands)