Cells- The smallest units
of Life
Breast Cancer Cell
Make a list of 5 different cell types
that can be found in your body and
explain what their function is
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Skin Cells- protection
Nerve Cells- impulse transmission
Muscle Cells- movement
Antibodies- disease prevention
Red Blood Cells- oxygen transport
SWBAT identify the components of
the cell theory and identify some basic
organelles found in most cells
• Cancer cell being attacked by
immune system cells
Cell- basic units of structure and function in living things
History
1600’s
Anon Van Leeuwenhoek- Dutch Biologist- built first simple
microscope
-discovered: bacteria, protists, sperm cells, blood cells to
name a few
Robert Hooke- English Scientist, first to study cells (cork)
1800’s
Robert Brown- Scottish, discovered the nucleus
What can we
actually see?
CELL THEORY- Based on historical
data
1 All living things are
composed of cells
2 Cells are the basic
structure and function of
living things
3 Cells come from other cells
Eukaryotic Organisms have 3
basic structures in common
1 Nucleus 2 Cell Membrane 3 Cytoplasm
Nucleus- information center and directs all activities in the cell
where DNA is found
How do Prokaryotes and Eukaryotes differ in terms
of the nucleus?
Nuclear Envelope- surround the nucleus
Nuclear Pores- holes in envelope, allows for movement
Nucleolus- ribosome’s are made here
Chromosomes (Chromatin)- long strands of DNA that
contain genetic info for reproduction
Prokaryote vs. Eukaryote
Sketch a Prokaryote Cell and Label in your notes
Cell Membrane- surrounds the cell and regulates
what enters and exits the cell
adds support and some limited protection
Made of phospholipids, Cholesterol- helps
maintain structure, Proteins and Carbohydrates
Phospholipids have a charge of 0 and are
polar - one end +
Create a lipid-bi-layer
Heads face out, tails in
Sketch in notes
Cytoplasm- jelly-like fluid that the organelles are found in
Cytoskeleton- structural element that make up the cytoplasm
made of 2 main parts
Microtubules- hollow tubes of protein
Organelles can move around the inside of the cell on
these
Form centrioles in animal cells
Help move chromosomes around during cell division
Some single celled animals they form cilia and flagella
Microfilaments- smaller than microtubules
Help with support and organelle movement
What are 3 structures that Eukaryotic cells
have in common and what is their function
in the cell?
SWBAT identify the organelles of the
cell (plant/animal)and their functions
1 Mitochondria- where cellular respiration takes
place
-found in both plant and animal cells
-powerhouse of the cell
2 Ribosomes- where proteins are assembled
-made of RNA and proteins in the nucleolus
-smallest of the organelles
-can be attached or free
-translate mRNA into polypeptide chains
-made of 2 subunits
-both plant and animals
contain ribosomes
3 Endoplasmic Reticulum
Smooth- synthesize lipids, detoxify drugs(liver), stores Ca,
stores enzymes, and transports
Rough- has ribosomes attached to it, modifies proteins from
protein synthesis
4 Golgi Appratus- flattened stack of membranes that modifies,
collects, packages and distributes molecules
-makes lysosomes
-last stop for a molecule before it leaves the cell
-both plant and animals have these
Can you tell the difference
between ER and Golgi?
5 Lysosomes-suicide sacs, destroy foreign material and recycle
cell parts
-found in animals and plants? (hotly debated)
-Tay Sachs Disease- no lysosomes, can’t metabolize fats,
builds up in brain (100% fatal)
http://highered.mcgraw-hill.com/olc/dl/120067/bio01.swf
Animation
6 Chloroplast- site where photosynthesis takes
place
-found in plants, some protists and some bacteria
7 Cell Wall
-protects and supports most cells
-only found in plants
-very porous
-made of polysaccharide - cellulose
-has pectin- sticky (polysaccharide), helps hold cells together,
breaks down to a monosaccharide as fruit over-ripens
-wood bearing plants have lignin- makes cellulose rigid
8 Vacuoles- storage sites for water, salts, proteins, and
carbohydrates
-found in animals and plants but are different sizes
9 Plastids- organelles of storage
Chloroplasts- stores chlorophyll
Chromoplasts- store pigments other than
chlorophyll
Leukoplast(Amyloplast)- storage of
starches
Starch grains in a
potato tuber
Explain through a sketch how you
can tell a plant cell from an animal
cell if you were looking through a
microscope.
• Chloroplast
• Cell Wall
• Large Vacuole
SWBAT recognize and understand
the 3 different passive transport
processes
Cell Movements
-cells are surrounded by liquid which makes movement
of molecules easier
Plasma (Cell) Membrane Types (depends on what
is trying to get
1Permeablethrough
2Semi/Selectively Permeable
3 Impermeable
Passive Transport- movement of molecules
without the use of energy
1 Diffusion- movement
of molecules from areas
of high concentration to
areas of low
concentration until
equilibrium is reached
http://highered.mcgrawhill.com/sites/0072495855/student_view0/chapter2/animation__how_diffusion_works.html
2 Osmosis- movement of water from areas of
high concentrations to low concentrations
through a semi-permeable membrane until
equalibrium is reached.
- both work on concentration gradients
- phospholipid membrane is permeable to water
- Penicillin- disrupts bacterial cell wall structure
and kills by osmotic pressure
http://highered.mcgrawhill.com/sites/0072495855/student_view0/chapter2/animation__how_osmosis_works.html
3 Facilitated Diffusion- molecules are moved
across a membrane by a carrier protein, from
high conc. to low conc.
- must have a conc. gradient
- ex: moving glucose into red blood cells
Animation facilitated diffusion
Hydrostatic Pressure- known as osmotic pressure, is the
pressure of water placed on walls and membranes
How do Single Celled Organisms compensate for
osmotic pressure
1 minimize contact with fresh water
2 have a cell wall (plants/bacteria) to resist expansion
(balloons)
3 have a contractile vacuole- type of active transport
which moves water out
Sketch a series of diagrams showing the
difference between the 3 passive
transport processes discussed last class
SWBAT recognize and understand
the different kinds of active transport
Active Transport- processes that require energy and
generally move materials against a conc. gradient
1 Molecular Pumps- use energy to pull molecules
across a membrane
Ex: Contractile Vacuole
Ex: Sodium Potassium
http://www.brookscole.com/chemistry_d/templates/student_resources/shared_resources/animations
/ion_pump/ionpump.html
2 Endocytosis- bringing large materials into the cell by
folding the cell membrane
A Pinocytosis- taking in large amounts of liquid
B Phagocytosis- taking in large amounts of
solids
3 Exocytosis- removing large amounts of material from
the cell
summary
http://highered.mcgraw-hill.com/olc/dl/120068/bio02.swf
Explain the differences between the
different kinds of Active Transport
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Molecular Pumps
Endocytosis
Pinocytosis
Phagocytosis
Exocytosis
SWBAT understand the levels of
organization in living organisms and
recognize some specialized cell types in
the human body
Cell Specialization
-all cells have a specialized
function within an organism
Specialized CellsPancreas- contain large
amounts of organelles involved with
protein synthesis (ER, RIbosomes,
Golgi) make enzymes that go
to your stomach for digestion
Lungs- lined with cells that have
cilia- hair-like projection that helps
clean the air
also can secrete mucus
which can be coughed up at your
convenience
Red Blood Cells- specialized for
oxygen transport
White Blood Cells- fight against
disease (lysosmes)
Levels of Organization in Multicellular
organisms
Cells
Tissues
Organs
Organ System
Organism
Tissues- cells are organized into tissues and they
perform a particular function
4 tissue types
1 Muscle- contains muscle & nerve cells
2 Epithelial- linings for body cavities, ducts,
tubes- single layer (skin)
3 Nerve- many different types of nerve cells
(brain, spinal cord)
4 Connective Tissue- bone, blood,
cartilage, tendons, ligaments
Organs- groups of tissue working together to
perform a special function
-each muscle is an organ
-muscle- contains muscle, nerve and
connective tissue
-all needed to make the muscle function
properly
Neuromuscular Junction
Organ Systems- groups of organs working together to
perform specialized functions
10 organ systems in the human body
can you name them?
Division of labor- everything has a job, they all work
together for proper functioning, if something isn’t doing its
job the structure won’t work as a whole.
Improper functioning
Organism- Made up of organ systems
List the levels of organization and
use a human system as an example
Cheek Cells
Epithilial Tissues
Stomach Organs
Digestive System Organ System
Human Organism
SWBAT recognize the different
phase of mitosis and the cell cycle
Cell Growth and Cell Division
Why can cells only get so big?
- when cells get too big they become inefficient
- this means that their ability to move food, water, oxygen and metabolic waste
becomes slower
- cells must maintain an acceptable surface area to volume ratio
- when growth occurs the volume grows faster than the SA and the ratio
decreases
- when the SA and Vol. difference decreases the cell must die or divide
How can a cell grow larger but avoid the inefficiencies of increased size?
1 Avoidance- avoid the problem and stay small (bacteria, yeast)
2 Geometric Solutions
A Elongate or flatten out (bacillus bacteria, red blood cells)
B Fold your cell membranes (amoeba, intestinal cells)
C Hollow out center of cell (vacuole use in plants)
3 Increase Rate of Supply
A Move to areas of high or low nutrient concentration (Protists
(flagella)
B Get bulk nutrients- food vacuoles (Amoeba, Paramecium)
C Improve Transportation Intracellularly- (Cyclosis in leaves)
-move nutrients away from membranes quickly
4 Improve efficiency to reduce demand
A Division of Labor (Intracellulary) (organelles in eukaryotic cells)
B Division of Labor (Intercellulary) (cell specialization, cells join
together)
Cyclosis- cytoplasmic streaming
Ameoba Feeding
Rates of Cell Growth
- different cells will grow at different rates
- cell growth is at its maximum under ideal conditions, know difference between
real and ideal conditions
E. coli- under ideal conditions can double itself approximatly every thirty minutes
- ideal conditions usually only happen in spurts
http://www.dnai.org/text/mediashowcase/index2.html?id=591
Bacterial Cell Division
- some cells divide rarely if at all - nervous system, heart (cardiac muscle)
- some cells divide rapidly- skin, digestive system
Expt: Growing cells in a petri dish
-cells were cultured in a petri dish until a thin layer covered the bottom and
then the growth stopped. Why?
Anchorage Dependence- cells attach themselves to keep from being separated
from their normal surroundings and from dividing inappropriately.
Density Dependent Inhibition- cells will divide to form a single layer and stop
dividing when they touch each other
cell division slows as density increases
analogous to cutting yourself
Growth Factor- proteins that stimulate cell division
Most cells stop dividing when they run out of growth factor
Chromosome Organization
Chromosome- (colored-body) contain the genetic information of an organism
Chromatin - makes up chromosomes- just visible before the start of CD
DNA- makes up the chromatin
Histones- proteins DNA are coiled around
Nucleosomes- tightly coiled histones
smallest
Histone
Nucleosome
Chromatin
largest
chromosome
Chromosome Structure
Chromatids- identical forms
across from each other
Centromere- central structure that
joins the chromatids
The Cell Cycle- follows the life of the cell
- includes: cell growth, preparation for division, cytokinesis
- all cells move through it at different rates
- one turn covers birth to division/death
Cell Cycle includes the following: Interphase, G1, S, G2, Mitosis
G2- growth needed for cell division
Gap 1
cell growth and
development
Interphase- includes G1, G2, and S phases
S- DNA synthesis (replication)
The Cell Cycle- follows the life of the cell
- includes: cell growth, preparation for division, cytokinesis
- all cells move through it at different rates
-one turn covers birth to division/death
-CANCER- uncontrolled cell growth
Cell Cycle Animation
http://www.cancerquest.org/index.cfm?page=58
Mitosis- cellular division (nuclear)
Cytokinesis- splitting of cell into 2
daughter cells
Phases of Mitosis
Prophase- longest phase
- cells spend 50 to 60%
of time here
- chromosomes start to appear
centrioles separate and move to
opposite sides of the nucleus
- spindle fiber forms
- chromosomes attatch to the
spindle
- nucleolus dissappears and
nucleus breaks apart
Prophase Animation
http://www.phschool.com/science/biology_place/biocoach/mitosisisg/prophase.htm
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Plant Prophase
http://www.phschool.com/science/biology_place/biocoach/mitosisisg/prophase.htm
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Animal Prophase
Metaphase
- shortest phase
- chromosomes line up on the
equator
- centromeres attach to the
spindles
Metaphase Animation
http://www.phschool.com/science/biology_place/biocoach/mitosisisg/meta.html
Anaphase
- centromeres split
- sister chromatids split and move
towards the poles
- cytokinesis starts here- in late
anaphase (the cell starts to split)
Anaphase Animation
http://www.phschool.com/science/biology_place/biocoach/mitosisisg/anaphase.htm
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Telophase
-final phase
- chromosomes began to uncoil
- nucleus begans to reform around chromatin
- spindle breaks up
- nucleolus becomes visible in both cells
- cytokinesis continues, plants do not go through
cytokinesis they form a CELL PLATE
- mitosis is complete, cytokinesis is not
- PLANTS ONLY- Cell Plate forms
Telophase animation
http://www.phschool.com/science/biology_place/biocoach/mitosisisg/telo.html
Mitosis Summary
http://www.sumanasinc.com/webcontent/animations/content/mitosis.html
Interactive
http://www.cellsalive.com/mitosis.htm