1. science
2. medicine
3. genetics

Cell Reproduction Intro
1) What do you know about
DNA, Genes and
Chromosomes?
2) What do you want to learn
about DNA, Genes and
Chromosomes?
1/29/14
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Find your new seats!
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Bellringer: Cell Reproduction Intro
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Chromosome Notes
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HW: Karyotype Worksheet due Tomorrow
Chromosomes!!!
Introduction to Chromosomes
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All of a cell’s DNA is called its “genome”
This genome contains all of the instructions for
cell/organism survival and function
A typical human cell has about 3 meters of
DNA
DNA is packaged into chromosomes
Chromosomes
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PROKARYOTIC
Chromosomes
are simple
circles/clumps of
DNA
Chromosomes
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EUKARYOITC
Chromosomes
are very complex
The whole
chromosome is
made of DNA
coiled around
proteins called
histones
Chromosomes
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Homologous Chromosomes:
The pairs of chromosomes that
exist in sexually reproducing
species
In each pair of h. chromosomes
one chromosome comes from
each parent
They are each called
autosomes, and are identical
(except X and Y, the sex
chromosomes)
Homologous Chromosomes
 Homologous
chromosomes
contain genes for
the same traits
 Gene: A section of
DNA that codes for
a specific trait
 Ex: Hair color
Homologous Chromosomes
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Before a cell divides,
the chromosomes
copy themselves
The two copies are
called chromatids
(or sister
chromatids), and are
attached to one
another by a
centromere
A
a
A
Aa
a
replication
Alleles are different forms of the same gene
1 chromosome
Karyotype
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A picture of all the chromosomes.
It is used to look for abnormalities
Revisit Goals
1)
2)
3)
Find 1-2 goals that you did not meet (or are off-track)
…Explain why you didn’t reach these goals
Find 1-2 goals that you did meet (or are on-track)
…Explain why you did reach these goals
Make at least 6 second semester goals on your goal sheet
(measurable)
2+ Academic
2+ Personal Improvement
2+ Work/Family/Relationships/Clubs
1/30/14
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Bellringer: Goals
HW: New Goals
Chromosome Notes (Chromosomal Disorders)
Go over karytype WS
Introduce Chromosomal Disorders Brochure
Straight to the Library tomorrow
Chromosome Number
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Number varies by species
The number of chromosomes in a SOMATIC CELL
(normal body cells) in an organism is known as the
DIPLOID/2N number
GAMETES (sex cells, sperm/eggs) contain only half
the number of chromosomes and are known as the
HAPLOID/N number
Complexity Rankings
Rank the below organisms from least to most complex
 Humans, Crabs, Potato, Camels, Squirrels, Chickens,
Fruit flies, Tomato

Explain the reason behind your rankings.
DIPLOID # OF CHROMOSOMES
BY SPECIES:
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CAMEL = 70
SQUIRREL = 40
CHICKEN = 78
KING CRAB = 208
FRUIT FLY = 8
TOMATO = 24
POTATO = 48
HUMAN = 46
Human Chromosome Number
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Human Haploid (N) Number: 23
Human Diploid (2N) Number: 46
A human must have all 46 chromosomes to
function “properly”
In most cases, humans missing even one
chromosome don’t survive development
Monosomy: missing a chromosome
Trisomy: having an extra chromosome

Nondisjunction: when homologous pairs or
sister chromatids fail to separate
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Down’s syndrome: (trisomy 21) 3 copies of the
21’st chromosome
Cri-du-chat:
deletion at the 5th
pair
Klinefelter:Extra X
chromosome
Goals:
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Review Goals and Make new ones…
1/31/14
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Bellringer: Goals
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Go Straight to LIBRARY
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Work on Karyotype Worksheet and
Brochure…
Bellringer
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Define the word “cycle”.
What is the cell cycle? If you don’t know, what
would you guess it includes?
Are all cell cycles the same?
2/3/14
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Objective: To introduce the cell cycle
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Bellringer: “Cycle”
Cell Cycle Notes
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Homework:
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Chromosome WS
Cell Division
Cell Division
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Cells divide in order to
repair or replace cells
that die
Also create new cells in
development of a
multicellular organism
that begins as a zygote
Cell Cycle
Cell Cycle: The life cycle of the cell,
from division to division of a cell
5 Stages of the Cell Cycle:
1.
G1: Growth phase of the cell
2.
S: DNA is copied
3.
G2: Prep for mitosis, and organelles
are copied
4.
M: Mitosis occurs, nucleus divides
5.
C: Cytokinesis, cell/cytoplasm divides
Interphase
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MOST OF A CELLS LIFE IS SPENT IN
INTERPHASE
What Triggers Cell Division?
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Size: If a cell grows so large that there is too
much volume for its surface area, it will divide
Growth factors: Chemicals released by cells
that encourage other cells to divide
Cell Division
There are 2 types of cell division
MITOSIS:
 Produces identical cells
 Occurs in body cells
 Makes diploid cells
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2 Types of Cell Division
MEIOSIS:
 Produces sex cells (gametes)
 Occurs in cells of the sex organs
 Makes haploid cells
Bellringer
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Define cell cycle
We know cellular division is part of the cell
cycle. Name one thing that you think happens
during cell division.
2/4/14
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Bellringer: Cell Cycle
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Turn in Chromosome Worksheet
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Onion Cell Pre-lab (due Friday)
Bellringer….
2/5/14
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Bellringer: ?????
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Computer Lab Activity
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These are the stages of mitosis. Put them in order,
and have a rational for why (you don’t need to write it,
but I will ask.)
B
A
D
C
E
2/6/14
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Bellringer: Stages of Mitosis
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MITOSIS NOTES
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Homework: Finish Pre-Lab
(I’ll explain later)
Stages of Mitosis
Stage 1:Prophase
 Chromosomes appear
 Nuclear envelope
breaks down
 Spindle fibers appear
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Spindle fibers are
protein ropes that help
pull chromosomes
apart
Late prophase – you can see the spindle fibers
Stages of Mitosis
Stage 2: Metaphase
 Meta means “middle”
 Spindle fibers line up
chromosomes on the
equator

They attach to the
centromeres
Metaphase
Stages of Mitosis
Stage 3: Anaphase
 Sister chromatids are
pulled apart by spindle
fibers
 Each chromatid (now a
chromosome) moves to
opposite poles
(centrioles)
Stages of Mitosis
Stage 4: Telophase
 Chromosomes uncoil on
separate sides of the
cell
 New nuclear envelope
appears
Cytokinesis: After Mitosis
Cytokinesis:
 Cell membrane grows in
to enclose both cells;
cytoplasm divides
 In plants, a new cell wall
must form
Mitosis
produces
two identical
daughter
cells which
are diploid
Mitosis in Onion Root
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These are the stages of mitosis. Put them in order,
and have a rational for why (you don’t need to write it,
but I will ask.)
B
A
D
C
E
Mitosis overview
Homework
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Somewhere on the pre-lab from yesterday, do
the following:
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Label each cell drawing 1-9 as interphase,
prophase, metaphase, anaphase, telophase, and
cytokinesis
You don’t have to use every phase
Bellringer
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Define Mitosis
Define chromosome
What kind of cells did we look at in the lab
from the last few days?
2/7/14
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Bellringer: Definitions
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Onion Lab
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Homework:
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Lab due Monday
Mitosis in Onion Root
Bellringer
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Define haploid and diploid
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Why do we want our sex cells (sperm and
eggs) to be haploid?
2/10/14
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Bellringer: No Bellringers This week….
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Agenda:
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Discuss week
Notes on meiosis
Sub all week..
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Tuesday: Work on Flipbook
Wednesday: No School (Lincoln)
Thursday: Cancer Article / Questions
Friday: Meiosis/Mitosis Worksheet &
Study Guide*
*I’m back Monday, exam is Tuesday
Meiosis
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Meiosis is a special kind of cell division that
produces our gametes (sex cells, sperm and
egg)
Occurs in testes and ovaries
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1 diploid cell(2n) →4 haploid cells (n)
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Fertilization creates a zygote and restores the
diploid condition
Egg (n) + sperm (n) →→ Zygote (2n)
Meiosis Overview
There are 2 cell divisions in Meiosis:
1.
Meiosis I: DNA replicates, and homologous
chromosomes are separated
1.
Same amount of DNA is started with
Meiosis II: Same steps as mitosis, but without
DNA being replicated beforehand
2.
•
Sister chromatids are separated
Meiosis
Crossing Over
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During Meiosis 1, Homologous pairs form their
sister chromatids
The two pairs of chromatids line up together in
what is called a tetrad.
When they do this, crossing-over occurs
 Homologs swap small pieces of genetic info
Independent Assortment
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Independent
assortment: mom’s
chromosomes don’t
always go to same side
nor do dad’s
Crossing over and
Independent
Assortment leads to
greater genetic diversity,
which is good for
populations!!!
Bellringer
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“If children have the ability to ignore all
odds and percentages, then maybe we can
all learn from them. When you think about it,
what other choice is there but to hope? We
have two options, medically and
emotionally: give up, or Fight Like Hell.”
What triggers cells to divide/start mitosis?
What could trigger them to stop?
What do you know about cancer? Do you know
Agenda
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Objective: To discuss cancer
Agenda:
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Bellringer/Discussion
Notes
Grade WS
Assign Mitosis Wheel and Practice
Homework:
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WS due Tomorrow
Wheel due Monday
What Stops Cell Division?
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Density-dependent inhibition: Cells stop
dividing when crowded
Cancer cells do not respond to normal cell cycle
regulation
Tumors
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Tumor cells are the result of uncontrolled cell
division (they are a big “lump” of cells)
 Benign tumors: non-harmful
 Malignant tumors: harmful
Cancer kills because a tumor makes some
essential part (lung, heart, etc…) stop working
right
Tumors
Malignant Tumors
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Cells divide without control and can invade
other tissues (metastasize).
Cancer cells can spread to other parts of the
body through the blood and lymph systems.
Cancer Types
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Carcinoma: begins in the skin or in tissues
that line or cover internal organs.
Sarcoma: begins in bone, cartilage, fat,
muscle, blood vessels, etc
Leukemia: starts in blood-forming tissue such
as the bone marrow
Lymphoma and myeloma: begin in the cells
of the immune system.
Central nervous system cancers: begin in
the tissues of the brain and spinal cord
Lung Cancer
Cancerous Lung
Healthy Lung
Skin Cancer
Detection
Treatments
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Chemotherapy
Radiation treatment
Surgical removal of tumors
Immunotherapy
Blood and marrow transplant
** There is NO cure for cancer **
Bellringer
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What components need to be in your psych
lab report?
What are the characteristics of a good
materials section?
What are the characteristics of a good
procedure?
What formatting applies?
Bellringer
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What would you guess is the most common
form of cancer?
What do you think is the most lethal spot for
cancer?
Agenda
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Objective: To talk a bit more about cancer,
and begin reviewing
Agenda:
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Bellringer/Discussion
Talk cancer rates
Grade Mitosis WS
Assign Practice WS and wheel
Homework:
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Wheel due Monday, WS due tomorrow
Common Forms of Cancer
Self Checks
All:
 CHECK YOURSELF!
 Colonoscopy once every 10 years after turning 40-50
Women:
 Monthly breast self-exam once you start menstruating
 Yearly gynecology visits for pelvic exam and pap smear
after the age of 21
Men:
 Monthly testicular exam at age 14
Bellringer
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Get out your study guide.
What areas are you most concerned about?
What areas are you least concerned about?
Comparing Mitosis and Meiosis
Determine whether the following characteristics apply to mitosis, meiosis, or both, by putting a check in
the appropriate column. Advice: be consistent in your answers!
Mitosis
Meiosis
1.no pairing of homologous chromosomes
1. ______ _______
2.two divisions
2. ______ _______
3.four daughter cells are produced
3. ______ _______
4.associated with growth and a-sexual reproduction4. ______ _______
5.associated with sexual reproduction
5. ______ _______
6.one division
6. ______ _______
7.two daughter cells are produced
7. ______ _______
8.involves duplication of chromosomes
8. ______ _______
9.chromosome number is maintained
9. ______ _______
10.crossing over between homologous chromosomes may occur
10.______ _______
Chromosome numbers
The three11.chromosome
figures describe chromosomes
of three different
number is reduced
to half organisms.11.______ _______
For each one 12.daughter cells are identical to parent cell
12.______ _______
What is the haploid number (N) of chromosomes? How many chromosome would you find in a regular body cell? How many in
an egg or13.daughter
in a sperm cell?
cells are not identical to parent cell
13.______ _______
14.produces gametes
14.______ _______
15.synapsis occurs in prophase
15.______ _______
A.
N (haploid): ______
Body cell:
______
.B.
C.
N (haploid): ______
Body cell:
______
N (haploid): ______
Body cell:
______