OBJECTIVES 1/15/2015
WARMUP:
Please have a seat and take out your Hot Zone books.
Agenda:
1. Discuss Microbiology Quiz and Hot Zone (pt 1 quiz)
2. Discuss Karyotypes
3. Introduce Embryology
4. Hot Zone Reading Session (if time)
HWK:
Articles are due on Tuesday (be prepared for 3-4 open note quizzes)
Please work on the Review Sheet (this is on my teacher site)
Embryology Quest and Review Sheet due Tuesday
Locate your textbook- Due on Friday 1/23
OBJECTIVES 1/15/2015
WARMUP:
Please have a seat and take out your Final Review Sheet and Answers
(#10-19)
Agenda:
1. Discuss Microbiology Quiz
2. Discuss Karyotypes
3. Introduce Embryology
4. Final Review Session (time to get ahead on your hwk)
HWK:
Final Review Packet- due Tuesday
Embryology Quest and Embryo Review Sheet due Tuesday
Locate your textbook- Due on Friday 1/23
Karyotypes
MALES
FEMALES
How much DNA do we have?
23 pairs of
chromosomes
Klinfelters Syndrome
Males who have have
an XXY pattern.
Physical development: Don’t make
as much testosterone as other boys.
Tend to be taller, less muscular
body, less facial and body hair, and
broader hips), larger breasts,
weaker bones, and a lower energy
level and infertility .
1 of every 500 males has an extra X
chromosome, but many don’t have any
symptoms.
Trisomy 21, is a
condition in which
extra genetic material
causes delays in the
way a child develops,
both mentally and
physically. It affects
about 1 in every 800
babies born in the
United States.
Downs Syndrome
Physically- flat facial profile, an
upward slant to the eyes, small
ears, and a protruding tongue.
Age 30 1 in 1,000
Age 351 in 400
Age 40 1 in 100.
Girls with Turner
syndrome are born with
only 1 X or they are
missing part of one X
chromosome.
Turners Syndrome
Girls with Turner syndrome are
usually short in height (4 feet 7in.)
Heart & kidney problems, over
weight, learning disabilities,
webbed neck, drooping eyelids
and more…
affects about 1 in every 2,500 girls.
Overview of Sexual Reproduction
• Sexual Reproduction is the combination of
genetic information from 2 different organisms
• Increases diversity in a population
• Sex cells AKA germ cells or gametes
• Created By Meiosis
• Meiosis is made up of 2 nuclear divisions:
• Meiosis I – homologous chromosomes
separate
• Meiosis II – sister chromatids separate
What happens here??
What happens here??
Interphase
Prophase I
Metaphase
I
What type of cell am
I??
Anaphase I
Cytokinesi
Telophase
I
Images from: http://www.phschool.com/science/biology_place/biocoach/meiosis/teloi.html
Coming from
Meiosis I
Prophase II
Metaphase II
Telophase II
Anaphase II
Images from: http://www.phschool.com/science/biology_place/biocoach/meiosis/teloi.html
Cytokinesis
HUMAN GAMETES:
• The Human Gametes are…
• Sperm – male (23 chromosomes)
• Ovum (egg) – female (23 chromosomes)
• Gametes are made through a specialized form
of meiosis…
• Spermatogenesis – formation of sperm
• Oogenesis – formation of ova
• Gametes are made in the gonads…
• Testes in males
• Ovaries in females
MEIOSIS
n=2
sex cell
sperm
n=2
n=2
2n=4
haploid (n)
n=2
diploid (2n)
n=2
n=2
meiosis I
meiosis II
SPERM- 4 parts
1
1. Acrosome – holds powerful
enzymes that help sperm enter
egg cell
2. Nucleus – 23 chromosomes
3. Midpiece – holds mitochondria
(provides energy)
4. Tail – 1 flagellum, allows sperm
to ‘swim’
2
3
4
Spermatogenesis
 This
process begins in puberty, continues
until death
Female Anatomy
OVUM
 Large
cell with a nucleus =23
chromosomes
 Large cytoplasm containing:
 Yolk – will be the precursor for blood
and reproductive cells, in organisms
other than mammals the yolk provides
the nutrients for the developing embryo
 Organelles – most importantly the
mitochondria
 Cell membrane – Which contains the
rest of the cell
 Layer of jelly – surrounds the cell
membrane and protects the ovum
Female Reproductive Organ
 The
ovaries are composed of sac-like structures
 Their job is to produce the ovum (eggs)
 Fallopian
tubes extend
from the ovaries to the
uterus
 They provide the pathway
for ovum to reach the
uterus
 They are the site of
fertilization
 Uterus
receives,
retains, nourishes the
fertilized ova
The Process of Oogenesis
A
female is born with a total supply of ovum
(eggs)
 Ability to release eggs begins at puberty and ends
at menopause
The Process of Oogenesis
 Only
one primary oocyte goes through
meiosis at a time, this occurs once a month
 If an egg is not fertilized it dies
OBJECTIVES 1/16/2015
WARMUP:
..
Agenda:
1. Finish Embryology
2. Embryology Review Sheet
3. Hot Zone Reading Session with remaining time
HWK:
Articles are due on Tuesday (be prepared for 3-4 open note quizzes)
Please work on the Review Sheet (this is on my teacher site)
Embryology Quest and Review Sheet due Tuesday
Locate your textbook- Due on Friday 1/23
OBJECTIVES 1/15/2015
WARMUP:
WARMUP:
..
Agenda:
1. Finish Embryology
2. Embryology Review Sheet
3. Hot Zone Reading Session with remaining time
HWK:
Final Review Packet- due Tuesday
Embryology Quest and Embryo Review Sheet due Tuesday
Locate your textbook- Due on Friday 1/23
Steps From Fertilization to Birth
 Fertilization
 Zygote
 Cleavage
 Morula
 Blastula
 Implantation
 Gestation
 Gastrula
 Embryo
 Fetus
Fertilization
 Fertilization
or conception – ovum
and sperm combining
 Ovum has 48 hours from time released to
be fertilized
 If not fertilized they dissolve (menstruation occurs)
Fertilization
 At
the same time, when a man ejaculates…
 About 300 million sperm are deposited in the vagina
 Only about 300 thousand reach the top of the
uterus
 And only 300 make it to the top of the Fallopian
tube where fertilization takes place
 Sperm, have approximately 48 hours before they die
Fertilization
 Sperm
must burrow through layers of
protective cells when they reach the ovum
 Sperm
breaks
through layers
meeting and
fusing with the
membrane
surrounding the
ovum
The steps of fertilization
1.
2.
3.
4.
5.
6.
Sperm contacts jelly layer and the egg cell
recognizes the proteins on sperm cell
Acrosome breaks and releases enzymes that
break the jelly layer around the ovum
Sperm forms a tube that pushes to the cell
membrane
Tube fuses with cell membrane
Sperm nucleus moves into the egg, tail stays
behind
Fertilization – officially occurs when the 2 nuclei
fuse
FERTILIZATION
 Within
~20 seconds a reaction occurs to form
fertilization membrane – blocks additional sperm
from entering the cell
 Why
would the entry of multiple sperm be bad?
FERTILIZATION
A
new cell called the zygote has been formed
 Diploid
 Will enter mitosis
 Genetic material will be
copied millions of times
and it will divide over
and over again
OBJECTIVES 1/16/2015
WARMUP:
..
Agenda:
1. Finish Embryology
2. Embryology Review Sheet
3. Hot Zone Reading Session with remaining time
HWK:
Articles are due on Tuesday (be prepared for 3-4 open note quizzes)
Please work on the Review Sheet (this is on my teacher site)
Embryology Quest and Review Sheet due Tuesday
Locate your textbook- Due on Friday 1/23
OBJECTIVES 1/15/2015
WARMUP:
WARMUP:
..
Agenda:
1. Finish Embryology
2. Embryology Review Sheet
3. Hot Zone Reading Session with remaining time
HWK:
Final Review Packet- due Tuesday
Embryology Quest and Embryo Review Sheet due Tuesday
Locate your textbook- Due on Friday 1/23
Stem Cells
 Cells
with the potential to develop into many
different cell types in the body.
 Stem cells are unspecialized (they do not
have a job in the body).
 Stem cells can divide and renew for long
periods of time.
Cleavage
 Zygote
first divides after about 24
hours after fertilization = cleavage
 After 3 days a solid ball of cells form=the morula
 Cells in the morula divide into hundreds of cells and
form a ring around a fluid filled cavity= blastocyst
 The blastocyst embeds itself in the uterine lining implantation
Fertilized egg
Cleavage – cell cycle without growth
Solid ball of cells
Implantation (blastula implants in the
endometrium of the uterus)
Hollow ball of cells AKA: blastula
Gestation
 Pregnancy
or gestation
begins at implantation
 After implantation cells
begin to differentiate or
gradually change into
specific cell types
 The 9 month period of
pregnancy is divided into
three trimesters
Embryo Or Fetus?
 What’s
the difference between an
embryo and a fetus?
Embryo
Fetus
Less than 8 weeks old More than 8 weeks old
Organ systems forming All organ systems
Looks like a ball of cells present
Looks like a tiny
human
Gastrulation
 Gastrulation=
the period of time when cells
differentiate into three major germ layers:
 Endoderm– digestive tract, respiratory system,
liver, pancreas
 Mesoderm – muscles, tissues, bones
 Ectoderm – skin, brain, nervous system
 Results in a Gastrula= a hollow ball with 3 distinct
germ layers
Important Membranes of the Fetus
 Amnion-
forms the amniotic sac
 surrounds and protects
developing embryo
 Yolk sac – provides nutrition
& site of formation
of first blood & reproductive
cells
 Chorion- Surrounds all other
membranes
 Chorionic villi –forms the placenta
See figure 52-9
The Placenta
 The
placenta creates
an area of exchange
between the mother
and baby
 Blood of mother and
baby never mix
 Constant exchange of
nutrients, gases,
pathogens, drugs and
other substances
 Fetus is attached to the
placenta by the
umbilical chord
SPERMATOGENISIS:
DIFFERENTIATION
MEIOSIS II
MEIOSIS II
MEIOSIS I
MEIOSIS I
MITOSIS
MITOSIS
Spermatide
DIFFERENTIATION
Word Bank:
differentiation,
Spermatogonium
meiosis I,
2* Spermatocyte
mitosis,
Spermatogonium
meiosis II,
Sperm
sperm
spermatogonium
1* spermatocyte
spermatid,
OOGENISIS
2* spermatocyte
Polar
Body
1* Oocyte
ovum,
Polar Body
polar body,
Oogonium
oogonium,
2* oocyte
1* oocyte
oogonium
Otid
Ovum 2* oocyte
1* Spermatocyte
First Trimester
 Month
1
 Fertilization, Cleavage,
Implantation, Gastrulation
 HCG (hormone) is produced
 Month 2 & Month 3
 Nervous system is the first
organ system to form.
 Heart develops and begins
beating
 All other organ systems begin
to form.
 Placenta forms and the
umbilical cord connects
mother and embryo.
First Trimester
Second Trimester
 Month
4, 5 & 6
 Accessory organs form. (Nails,
eyelashes, eyebrows)
 Baby moves (can suck its
thumb, kick and punch)
 Doctors can tell if it is a boy or
girl
 Mother can feel baby moving
 Skin is covered by soft hair
 lungs begin to develop
21 wks
28 wks
Second Trimester
Third Trimester
 Months
 Organs
7, 8 and 9
continue to develop
 Starts to gain fat under
skin
 Size increases rapidly
 The immune system
develops
 Can sense light and
darkness and react to
36 wks
sounds
 Labor will be triggered by
the release of a hormone
called oxytocin
Labor
 Dilation
 Oxytocin
is released causing:
 Contractions to begin
 Cervix to dilate
 baby’s head pushed down
 amniotic sac bursts (water
breaks)
 Expulsion
 Cervix is fully dilated (10cm)
 Contractions occur every 1-2 min.
 The child is delivered
 Afterbirth
 The placenta (afterbirth) is
delivered
Premature Birth
A
baby can survive if born 23 weeks early (during 2nd
trimester)
 Increased risk of developmental and medical problems
 1 in 10 babies are premature
 Causes:
 Rupture of amniotic sac
 Certain infections
 Weak cervix (from previous pregnancy)
 Uterine abnormalities
 Previous premature delivery
 Substance abuse
 Malnutrition
Twins
 Monozygotic
twins
twins
 They are
 Non-identical twins
genetically identical  Occurs when two or more
 Occurs when the
eggs are released by the
fertilized egg splits
mother at a time and are
completely in half
fertilized by two different
during cleavage
sperm cells
Identical Twins
 Dizygotic
Fraternal Twins
1.
…
…
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