Transcript Unit 9: Reproduction and Development

Unit 9: Reproduction and
Development
How are humans made?
A. Sexual Reproduction
________________________
offspring are a ____________ of parental genes
1. Advantages for Sexual Reproduction
- _________ allows for adaptation to new environments
- ______________
- _________________________
2. Meiosis and Gamete Formation
- __________________ - Reduction Division
- _________ - in humans this means the cell goes from
___ to ____ chromosomes
a) Definitions:
- _________ = process of cell division to make _______
cells and _____ cell (___________)
- ________= 2n  the cell has two sets of chromosomes
in humans the diploid number is 46
23 chromosomes from _______ and 23
chromosomes from ______
- _________________ = n  the cell has one set of
chromosomes
______________________ are haploid  they
only have 23 chromosomes
b) Process of Meiosis
- meiosis only happens in ________ = _____________
male gonad = ________ female gonad = _______
- meiosis produces sex cells (gametes) which have half the
number of chromosomes as compared to normal body
cells
- meiosis involves the cell dividing ________
1) DNA Replication
DNA in the nucleus copies - 46 chromosomes becomes 92
Cells – Chromosomes - DNA
2) Nucleus Disappears and Chromosomes Pair Together
- ________________________ = the processes by which
homologous chromosomes pair together and switch
genes
- _______________________ = similar chromosomes of
the same size and shape; they carry to same kind of
genes but may have different forms of the genes on
them
- Synapsis and Crossing over increase the _____________ in
offspring  it is one of the reason why you and your siblings
do not look exactly alike
- In crossing over, __________ of homologous chromosomes
switch chromosomes and rearrange genes
3) Cells and Chromosomes Separate (2x)
- Cell divides the chromosomes cell material twice
- Makes ___________________
- Each daughter cell has 23 chromosomes
Why would you make cells
with half the number of
chromosomes?
4) Meiosis in Males and Females
Males:
- make 4 sperm cells
- meiosis happens all the
time
Females:
- make ___ viable egg cell
and 3 polar bodies
- meiosis happens once a
month
3. Fertilization
- ________________________________
- combination of male and female gametes
- n + n = 2n  23 + 23 = 46 – combining chromosomes of
the parents
- formation of a _________ = single cell that will become the
baby
sperm
egg
zygote
4. Human Reproduction
a) Male Reproductive System
1) _________ - make and store sperm
- Produce the hormone ___________________
- Scrotum - saclike pouch which houses the testes
for proper sperm production the scrotum is __________
celsius below normal body temperature
- Seminiferous tubules - carries/stores sperm from the
testes
2) ___________ - temporary storage organ for sperm at the
beginning of the Vas Deferens
3) _______________ - tube which carries the sperm past 3
lubricating glands
- _____________ - removal or tie up of the Vas Deferens
Stops sperm from being released from the body
4) Cowpers gland, Seminal Vesicle, Prostate Gland –
- 3 lubricating glands
- prostate produces an alkaline fluid which neutralizes the
urine in the urethra
- ________________ kills many over 70 males
- treated with radiation and estrogen
5) _________ - tube through the penis
6) ________ - releases the semen inside the female
- ___________ - liquid loaded with sperm
- ____________ - the release of semen
b) Female Reproductive System
- functional from puberty until menopause
1) _____________ – produce ovum = egg cells
- Usually only one egg is released at a time
2) _____________________ - muscular contractions of the
oviduct and beating of its cilia draw ovum into the oviduct
- Normally fertilization and initial cleavage occurs in
fallopian tubes
3) _____________ - spongy bed in which the zygote will
become implanted and develop
- embryonic development occurs here
4) _________ - narrow neck of the uterus
- Cancer of the cervix is common  ____________
5) ____________ – birth canal and opening to the outside
of the body
- site where sperm are deposited
6) Menstrual Cycle
- hormone controlled process by which the ____________
and is released; it prepares the body for _____________
Stages:
1. ___________________ (10-14 days)
- production of ova occurs in tiny cavities in the ovary called
follicles
- enlarging follicle produces ___________ which causes the
uterus to get ready for embryo implantation (thickens its
lining)
2. ___________________ (1 day)
- follicle enlarges & ruptures ovary wall
- egg is __________ to the oviduct
3. ___________________ (10 -14 days)
- yellow tissue fills the follicle after ovulation
- called the corpus luteum "yellow body"
- secretes _____________ which readies the uterus for
pregnancy
4. ___________________ (3-5 days)
- periodic shedding of the thickened lining of the uterus which
_____________________________
5. Human Development
a) Fertilization
 sperm deposited in the vagina and swim up the uterus
to the Fallopian tubes.
_________________ the egg
_____________________
_____________________
b) Implantation
 as the fertilized egg travels down the Fallopian tubes it
goes through _________________
upon reaching the uterus the egg fastens itself to the
uterine lining and begins pregnancy
ectopic pregnancy
 __________  ________  _________
c) Differentiation – Cell Specialization - Growth
A – _________________
– site where mother and
fetus exchange nutrients,
wastes, O2, CO2
– blood __________ cross
between mother and fetus
B – _________________
– rope like tube that carries
the nutrients and wastes to
and from the fetus
C – ___________
D – __________________
– surrounded by the
chorion (membrane) helps
protect the fetus and keep it
stable
d) Fetal Nourishment
Substances in the mother’s blood pass to the fetus
_______________________
_________________________
Viruses
e) Birth
______________ = length of pregnancy – 40 weeks (9 mon.)
______________ = muscular contractions of the uterus
premature birth
__________________
f) Growth  Puberty  Growth/Maintain  Death