Chapter 2- Reproduction

Front 1

S phase

Back 1

replicate genome (create chromatids)

Front 2

G1 & G2 phase

Back 2

gap phases, growth phases

Front 3

Mitosis

Back 3

2N=>2N, occurs in all dividing cells; 10% of cell cycle
Interphase – replication of genetic material resulting in sister chromatids
Prophase – chromosomes condense; spindles form, centrioles move
Metaphase – chromosomes align at plate
Anaphase – sister chromatids separate; shortest phase (late or early telophase – cytokinesis, separation of cytoplasm)
Telophase – new nuclear membranes form (cleavage furrow forms); spindles disappear, nucleolus reappears
* sequence = S, G2, P, M, A, T, G1
* Plants lack centrioles and divide by cell plate not cleavage furrow, divide by formation of a cell plate

Front 4

Meiosis

Back 4

occurs in sex cells, homologous chromosomes pair at meta plate (tetrads), crossing over can occur, 2N=>N
First Meiotic Division produces 2 daughter cells w/ N chromosomes w/ sister chrom
Prophase – chromatids of homologous chromosomes exchange genetic material (crossing over)
Metaphase – tetrads align at plate (synapsis); each pair attaches to a separate spindle
Anaphase – homologous pairs pulled to opposite poles (disjunction) / distribution to the two daughter cells is random w/ respect to parental origin
Telophase – nuclear membrane forms around each nucleus
Second division is very similar to mitosis. Note that only one becomes functional gamete in females

Front 5

chiasmata

Back 5

X-shaped region b/w diff. chromatids of homologous chromosomes

Front 6

kinetichore

Back 6

specialized group of proteins and DNA on a chromatid to which several spindle microtubles are attached; found within the centromere of each chromosome

Front 7

Synapsis

Back 7

pairing of homologous of chromosomes during meiosis I

Front 8

inversion

Back 8

chromosomal segment turned 180o

Front 9

Translocation

Back 9

2 nonhomologous chromosomes interchange genes (attachment of all or part of one chromosome to another)
***Mitochondria is an exception to the universality of the genetic code

Front 10

Nondisjunction

Back 10

failure of homologous chromosomes to separate during Meiosis I or sister chromatids to separate during Meiosis II; result in trisomy or monosomy; ex Down syndrome

Front 11

Turner syndrome

Back 11

sterile female lacking X chromosome

Front 12

Klinefelter Syndrome

Back 12

44 autosomes + XXY

Front 13

Asexual Reproduction

Back 13

production of offspring w/o fertilization
Binary Fission – prokaryotes; DNA replicates, wall grows inward along midwall; ex paramecia, amoebae, algae, bacteria
Budding – develops as outgrowth, forms smaller cell; ex hydra & yeast
Regeneration – regrowth of lost body part; ex starfish and hydra
Parthenogenesis – unfertilized egg to adult egg; ex bees and ants

Front 14

Gonads

Back 14

male = testes, female = ovaries

Front 15

Leydig cells

Back 15

in the testes, secrete testosterone

Front 16

Spermatogenesis

Back 16

sperm production in seminiferous tubules; head = nucleus & tail = flagellum

Front 17

acrosome

Back 17

membrane-bound structure at the anterior end of sperm cells; contains hyaluronidase (hydrolytic enzyme that causes the breakdown of protective surfaces of the egg)

Front 18

capacitation

Back 18

functional maturation of the spermatozoa while in the female, allows for egg penetration

Front 19

prostatic fluid

Back 19

helps neutralize the acidic vaginal secretions to enhance sperms’ ability to swim; also neutralizes seminal fluid (too acidic from metabolic waste of sperm)

Front 20

Oogenesis

Back 20

oocytes produced in ovaries

Front 21

Male Reproductive

Back 21

path of sperm SEVEnUP (seminiferous tub, epididymis, vas deferens, ejaculatory duct, urethra, penis)

Front 22

Female Reproductive

Back 22

fallopian tube opens to uterus (narrow end called cervix), cervix connects with vaginal canal

Front 23

The Menstrual Cycle

Back 23

divided into follicular, ovulation, luteal, menstruation
Follicular – FSH promotes development of follicle which secretes estrogen
Ovulation- peak in estrogen=> LH surge=> ovulation (midway through cycle) => mature follicle bursts releasing ovum
Luteal – LH induces follicle to develop into corpus luteum which secretes estrogen and progesterone (LH and FSH inhibited)
Menstruation – If fertilized placenta produces (Human chorionic gonadotropin) hCG (estrogen + proges levels remain high) // If NOT fertilized, corpus luteum atrophies to corpus albicans (drop in estrogen + prog) and menstrual flow begins

Front 24

Estrogen

Back 24

thicken endometrium

Front 25

Progesterone

Back 25

development and maintenance of endometrial wall

Front 26

Gametophyte generation

Back 26

haploid & produce haploid gametes thru mitosis; sexually reproduce; ex mosses

Front 27

Sporophyte generation

Back 27

diploid but produces haploid spore by meiosis; ex ferns and angiosperms

Front 28

Angiosperms

Back 28

flowering plants; flower is reproductive structure
Stamen – male organ; composed of stalk-like filament & sac-like anther (produces haploid spores that develop into pollen)
Pistil – female organ; composed of stigma (catches pollen), style, and ovary
Sepals – green leaves cover and protect flower bud during early development
Fertilization – 1 sperm nucleus + 1 egg nucleus => zygote => embryo 1 sperm nucleus + 2 polar nuclei => 3n endosperm
Seed formation – Epicotyl (precursor of leaves), Cotyledons (seed leaves), Hypocotyl (develops into lower stem and root), Endosperm (feeds embryo), Seed Coat (develops from outer covering of ovule)