Levels of Organization
2
Organ System
1
Organism
Cell
6 Organelle
3 Organ
Tissue
5
4
PAGE 3
What are the differences between
plant & animal cells?
circular shape
square shape
large vacuole
centriole
chloroplasts
cell wall
small vacuole
PAGE 3
Biotic
soil
earthworm
vs
Abiotic
maple tree
sunlight
mushroom
oxygen
human
PAGE 4
How do little elephants grow up to be
BIG elephants?
A. Living Organisms have a
Life Cycle
1. Begins with the
organism’s formation
2. Followed by growth
& development
3. Ends in death
PAGE 4
B. Cells also have life cycles.
C. The cell cycle is a series
of events that takes place
from one cell division to
the next.
PAGE 4
1.
2.
It takes different cells
different amounts of time to
complete a cell cycle
Some cells constantly repeat
the cycle
a. example: Red blood cells
Skin cells
PAGE 4
Cell
growth
DNA
(chromosomes)
are duplicated
Cell prepares
for division
Cell Division
Responsible for:
1.Growth
2.Repair
3.Replacement
4.Reproduction
PAGE 5
1. Mitosis
a. Part of a larger cell cycle
b. Occurs in the nucleus of eukaryotic
cells
c. Responsible for growth and repair,
replacement.
d. Replaces the entire lining of the
small intestine
1)Liver cells only
divide for
repairing
2) Nerve cells do not
divide
3) New cells arise by
division of existing
cells; Resulting cell
is capable to divide
again
Mitosis Notes
Cell division occurs in a series of stages
or phases
PAGE 6
Preparation for mitosis:
 Interphase
 genetic
not a part of mitosis
material is
(doubled)duplicated.
Nucleus
PAGE 6
CELL
MEMBRANE
Cytoplasm
Animal Cell
PAGE 6
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
1. Prophase
 Mitosis
begins
 nuclear envelope disappears
 chromosome pairs appear and
spindle fibers form between the
poles
Prophase
Centrioles
PAGE 6
Spindle fibers
Animal Cell
Plant Cell
Spindle fibers
Centrioles
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
2. Metaphase
 Chromosome
pairs line up in the
middle of the cell
 Chromosomes attach to the spindle
fibers
PAGE 6
Metaphase
Centrioles
PAGE 6
Spindle fibers
Animal Cell
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
3. Anaphase
 Chromosomes
separate & are pulled
to opposite ends of the cell
Anaphase
Centrioles
PAGE 6
Spindle fibers
Animal Cell
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
4. Telophase
nuclear
envelope forms again
chromosomes begin to separate
begin to see two cells
mitosis ends
Telophase
Nuclei
Chromatin
Nuclei
Animal Cell
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
Cytokinesis
moves inward
(
cell) to create
cells each cell has its own
with
nuclei
Cytokinesis
(animal cell)
Cytokinesis:Pinching In
ANIMAL CELLS
Cytokinesis
cell
forms
in the middle
of the cell
(
cell)
each cell has its own
with
nuclei
Cytokinesis
(plant cell)
Cytokinesis: Cell plate
ANIMAL CELLS
Pink Mice Are Totally Cute
http://www.cellsalive.com/mitosis.htm
http://www.biology.arizona.edu/cell_bio/tuto
rials/cell_cycle/MitosisFlash.html
Mitosis in Plants
Animal Mitosis -- Review
Interphase
Prophase
Metaphase
Anaphase
Telophase
Interphase
Plant Mitosis -- Review
Interphase
Metaphase
Telophase
Prophase
Anaphase
Interphase
2. Meiosis
 a.
Cell divides twice to become a
gamete (sex cell)
 b.
Will not divide any further until
fertilization.
E. There are two types of reproduction
among living organisms.
PAGE 8
1. Asexual Reproduction – a new
organism is produced from one
organism.
a. The new organism has
hereditary material
identical to the parent.
PAGE 8
Name of organism
Type of Asexual
Reproduction
potato
budding
Strawberry plant
runners
Hydra
budding
Sea star, planaria,
sponges
regeneration
PAGE 8
F. Sexual Reproduction
1. Two sex cells join to form a
zygote, which will develop into a
new organism that is not
identical to the parents.
a. There are two types of sex
cells.
Page 9
1. Sperm are made
in the male
reproductive
organs, called the
testes.
Sperm
2. Eggs are made in
the female
reproductive
organs called the
ovaries.
Page 9
Eggs
3. Sperm + Egg
zygote
This is called fertilization.
+
haploid +
23
+
Page 9
haploid =
23
=
diploid
46
Cells
Body
Diploid
46 chromosomes
Page 10
Sex
Haploid
23 chromosomes
Meiosis allows the creation of unique
individuals through sexual reproduction.
2. Meiosis – produces
four haploid sex
cells from one
diploid cell, this
makes sure that
offspring will have
the same number of
chromosomes as the
parent organisms.
Page 10
3.What is the difference between
diploid & haploid?
a. diploid – cell whose similar
chromosomes occur in pairs (2n)
b. haploid – cell that has half (n)
the number of chromosomes as body
cells.
Page 10
Draw this table in your notes on the bottom of page 10.
46 Chromosomes
(diploid)
23 Chromosomes
(haploid)
Heart Cell
Muscle Cell
Stomach Cell Liver Cell Egg Cell Skin Cell Sperm Cell
Page 10
Let’s Practice!
Organism Diploid Number
Haploid Number
Mouse
40
20
Chicken
78
39
Tomato
24
12
Housefly
12
6
Human
46
23
Page 11
What is DNA?
Deoxyribonucleic Acid
 Contains the genetic information: located
in the nucleus
Twisted ladder
 Shape of it is a double helix: looks like a
spiral staircase
 DNA is made up of many repeating units
called nucleotides
Phosphate group
5 carbon sugar
Nitrogenous Base
DNA Structure – Watson and Crick (1953)
Rosalind Franklin
X-Ray photo of DNA
(1952)
(Deoxyribonucleic
Acid)
What is a nucleotide?
1.
2.
3.
Sugar (5 carbon)
Phosphate group
Nitrogenous base (there are four
bases)  Cytosine C



T
Adenine A
Guanine G
Thymine
Each base has a compliment. That
means that it normally bonds with
another base.
For example:
A always bonds with T
C always bonds with G
Phosphate group
A
T
5 carbon sugar
Hydrogen bond
T
A
C
G
G
C
Nitrogenous base
nucleotide
Let’s Practice
T- A
C- G
G- C
A- T
A- T
T- A
T- A
G- C
C- G
C- G
Original Strand
Complimentary Strand
C- G
G- C
T- A
C- G
T- A
A- T
A- T
T- A
G- C
G- C
C- G
T- A
Chromosome Number
Transcription Translation
DNA
RNA
Protein Trait
RNA processing
Making Proteins
Step 1: DNA replication
 Step 2: RNA synthesis (Using a piece of
DNA to make RNA, called transcription)
 Step 3: Amino acids form proteins (called
translation)

DNA
RNA
Protein
RNA
 Is single-stranded
 Contains the sugar ribose
 Has the base U (uracil) instead of T (thymine)
 There are 3 types:
mRNA – messenger RNA
rRNA – ribosomal RNA
tRNA – transfer RNA
Making a protein
from the plans in
the DNA is a two
step process.
Transcription:
A messenger
RNA copy of the
gene is made.
Translation:
The mRNA is
sent to a
ribosome where
a protein is
made.