mitosis how do your cells divide? ch. 6 and ch. 7
TRANSCRIPT
A few words before we start…..
Haploid: (n) 1 set of unpaired chromosomes
Diploid: (2n)2 haploid sets of chromosomes(1 pair)
DNA Structure Ch. 9
Made up of nucleotidesThere are 3 parts to each
nucleotide–Deoxyribose sugar–Phosphate group–One of 4 Nitrogen bases
Nitrogen Bases
There are four possible nitrogen bases:
Adenine (A) Thymine (T)
Cytosine (C) Guanine (G)
A
G
T
C
Nitrogen Base Pairing
These bases always pair together in DNA:
Adenine (A) Thymine (T)
Cytosine (C) Guanine (G)
A
G
T
C
DNA Replication
Making a new strand of DNA is actually quite easy.
Replication occurs in 3 easy steps…
1. DNA Unzips
An enzyme unzips the molecule
The enzymes breaks the hydrogen bonds that hold the nitrogen bases together.
A
G
G
T T
C
C
Left StrandOriginal DNA
Right StrandOriginal DNANew Right
DNA Strand
DNA Replication Base Pairing
A
G
G
T
C
T
C
C
Left StrandOriginal DNA
Right StrandOriginal DNANew Right
DNA Strand
DNA Replication Base Pairing
Left StrandOriginal DNA
Right StrandOriginal DNANew Right
DNA Strand
A
G
G
T
C
C
T
C
C
DNA Replication Base Pairing
Left StrandOriginal DNA
Right StrandOriginal DNANew Right
DNA Strand
A
G
G
T
C
C
T
C
C
A
New LeftDNA Strand
DNA Replication Base Pairing
Left StrandOriginal DNA
Right StrandOriginal DNANew Right
DNA StrandNew LeftDNA Strand
A
G
G
T
C
C
T
C
C
A
G
DNA Replication Base Pairing
Left StrandOriginal DNA
Right StrandOriginal DNANew Right
DNA StrandNew LeftDNA Strand
A
G
G
T
C
C
T
C
C
A
G
G
DNA Replication Base Pairing
Now that DNA has replicated, we are ready to begin Mitosis (nucleusof the cell divides)
T
C
C
A
G
G
T
C
C
A
G
G
Parent CellDNA condenses into chromosomes
Chromosomes align on the equator
Chromosomes separate
DNA uncoils
Prophase
Metaphase
Anaphase
Telophase
MITOSIS
Cytokinesis
Cleavage (indention in cell membrane) or cell plate formation occurs.
Cell divides.
Animal Cell Plant Cell
Overview of the Cell Cycle
InterphaseC ell G row th
an d R ep lica tion
M itosisN u c lear D ivis ion
CytokinesisC ytop lasm D ivis ion
Cell Cycle
PMAT
It’s all about the chromosomes!– There are 46 in human body
cells– The number of chromosomes
remain constant during Mitosis
Which Cells Go Through Mitosis?
Growth
Repair
Work
Cells which help the body in:The cells are called autosomes
What happens if cell division gets out of control?
CANCERThe body doesn’t respond
normally to the body’s control mechanisms
p. 127, 138-139
Mitosis Review
1. Is the beginning parent cell diploid or haploid
(2n or n)?
2. Are the daughter cells diploid or haploid (2n or n)?
More Mitosis Review
3. How many daughter cells are produced?
4. Are the resulting daughter cells different from the parent cell?
More Mitosis Review
5. Are the resulting daughter cells different from each other?
6. How many chromosomes are in a human parent cell?
7. How many chromosomes are in a human daughter cell?