Transcript Chapter 7 A View of the Cell

December 6, 2010
Beginning with van
Leeuwenhoek Create a
time line with the names
of those instrumental in
discoveries connected
with the microscope and
the cell theory
Describe the cell theory.
Notes on 7.1/ 7.2
Problem Solving lab 7.1
NOTEBOOK
Check on 6
A
B
C
D
1600 1700 1800
A. Hooke – cork cells
B. Leeuwenhock – single lens, saw red blood
cells and bacteria
C. Schleiden – plants
D. Schwann – animal cells
Cell Theory
1. All organisms composed of 1 or more cells
2. The cell is the basic unit of organization of
organisms
3. All cells come from preexisting cells (cell
divides to form 2 identical cells)
Chapter 7
Cells
Muscle Cell
December 7, 2010
Bola Spider
No Web
Catches with a spider silk
thread with a sticky glob
on the end (bola)
Generates the same scent
as the female moth to
attract the male moth
600% elastic
Sticky irreproducible
adhesive
Catches up to 8 moths/nite
7.1 The Discovery of Cells
History of
Cell Theory
Cells
basic units of
living
organisms
Compound Light
Microscope
Series of
Lenses
Adjustable
Up to 1500x
magnification
van Leeuwenhoek – 1 lens
Object set on
top of screw
and adjusted
to bring into
view
Made most
discoveries
Robert Hooke – 1635-1703
Discovered and
named the first
Cell
Found in Cork
Named for
monastery cells
Theodor Schwann – 1810-1882
German
Discovered
animals made
of cells
Father of
cytology
Discovered
Schwann Cells
Developed the
Cell Theory
Matthias Jakob Schleiden
1804-1881
Discovered all
Plants made
of Cells
Together with
Schwann
developed the
Cell Theory
Cell Theory
1. All organisms composed of 1
or more cells
2. The cell is the basic unit of
organization of organisms
3. All cells come from
preexisting cells (cell divides to
form 2 identical cells)
Different Parts of the Microscope
Revolving
nosepiece
Eyepiece
Clip
Body tube
Coarse
adjustment
Fine adjustment
Condenser
Arm
Iris diaphragm
Stage
Objective
Mirror
Condenser
control knob
Base
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Electron Microscopes
1940’s – uses a beam of electrons instead
of natural light to magnify structures up
to 500,000x
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Scanning Electron Microscopes (SEM) scans surface of cells to learn 3D shape
Transmission Electron Microscope (TEM) study the structures contained in the cell
Scanning Tunneling Microscope (STM) –
uses flow of electrons to investigate atoms
on the surface of the molecule
Electron
Micro
scope
2 Basic Cell Types
1. Prokaryotes – Cells that do not have an internal
membrane bound structure – unicellular like
bacteria
2. Eukaryotes – cells containing membrane bound
structures multicellular like algae, yeast
Organelles – small membrane bound structures
allows various chemical reactions to occur
simultaneously
Brown, Virchov – decided main structure that was
responsible for cell division
Nucleus – central membrane bound organelle that
manages cellular functions
Prokaryotes
Nucleoid region
contains the DNA
•Cell membrane &
cell wall
• Contain ribosomes
(no membrane) to
make proteins in
their cytoplasm
http://sps.k12.ar.us/massengale/biology
Eukaryotic Cell
Contain 3 basic
cell structures:
Nucleus
Cell Membrane
Cytoplasm with
organelles
http://sps.k12.ar.us/massengale/biology
Two Main Types of Eukaryotic Cells
December 7, 2010
Draw and Label a
Prokaryote & Eukaryote
Cell
?? What is the function of
the plasma membrane?
Notes 7.2
PS Lab 7.2
December 13, 2010
Cell Function Worksheet – Due Wed
?? For Plant and Animal Cell Lab
Animal Cells – muscles, bone, cerebellum
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1. Are these cells alive (once living)?
2. Describe the shape of each cell.
3. Is there a cell wall?
Elodea Cell – plant
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1. Is the Elodea Cell alive (once living)?
2. Describe the color and shape of chloroplasts
3. Is a cell wall present?
7.2 Plasma Membrane boundary between the cell
and its environment
Homeostasis
– process of
maintaining
the cells
environment
Selective Permeability
– Process by which
the plasma
membrane allows
some molecules in
to the cell while
keeping others out
(selective – H2O,
Calcium, sodium,
glucose)
Structure of Plasma Membrane
Phospholipids – lipids with a
phosphate group attached to
them
Plasma membrane has a
glycerol backbone, 2 fatty
acid chains and a phosphate
group
Fluid Mosaic model
Model of the plasma membrane
where molecules are free to
move sideways within a lipid bilayer
Polar head outside attracts
water but is selectively
permeable
Other Components
Cholesterol – helps stabilize the
phospholipids, keeps them from
sticking together
Transport Proteins – proteins that
along the plasma membrane
creating a selectively permeable
membrane that regulates which
molecules enter and leave a cell
Fluid Mosaic Model
December 14, 2010
?? Of the day:
Describe the Fluid Mosaic Model of Cell
or Plasma Membrane – make sure to
draw a picture
Diffusion Pre-Lab with Notes
I will collect grade for Microscope Lab
Progress Reports – please have signed
and return for 10 pts
Cell Membrane
Diffusion Lab
Every cell is covered by a membrane that
controls what can enter and leave the cell. The
cell membrane or plasma membrane is
selectively permeable. It allows some
substances to enter and keeps some
substances out. This is important for all life
processes. A diagram of cell membrane
structure is below.
Diffusion Lab (cont)
The cell membrane is made up of lipids and
proteins. Small non-polar molecules can go
right through the membrane by osmosis
but ions or larger molecules need assistance
by either diffusion and/or by transport
proteins.
7.3 Eukaryotic Cell Structure
Contains Organelles:
Very small size
Can only be observed
under a microscope
Have specific functions
Found throughout
cytoplasm
Plasma Membrane Surrounding the Cell
Cell membrane
Lies immediately
against the cell wall
in plant cells
Made of protein and
phospholipids
Selectively permeable
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Cell or Plasma Membrane
Cell membrane
Living layer
Controls the
movement of
materials into and
out of the cell
Selectively
permeable
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Plant Cell - Cell Wall
Dead layer
Large empty spaces
present between
cellulose fibers
Freely permeable
Made of cellulose
which forms very
thin fibers
Strong and rigid
Found in plant cells
http://sps.k12.ar.us/massengale/biology
Plant Cell
Cell wall
Protect and support
the enclosed
substances
(protoplasm)
Resist entry of
excess water into
the cell
Give shape to the cell
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Control Organelle-Nucleus
Nucleus
Controls the normal
activities of the cell
Bounded by a
nuclear membrane
Contains chromosomes
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More on the Nucleus
Nucleus
Each cell has fixed
number of
chromosomes that
carry genes
Genes control cell
characteristics
http://sps.k12.ar.us/massengale/biology
Nucleolus
Cell may have 1
to 3 nucleoli
Inside nucleus
Disappears when
cell divides
Makes ribosomes
that make
proteins
http://sps.k12.ar.us/massengale/biology
Cytoplasm of a Cell
Cytoplasm
Jelly-like substance
enclosed by cell
membrane
Provides a medium for
chemical reactions to
take place
Contains organelles to
carry out specific
jobs
http://sps.k12.ar.us/massengale/biology
Smooth & Rough Endoplasmic
Reticulum –assembly and
transport of proteins
Smooth ER lacks
ribosomes &
makes proteins
USED In the cell
Rough ER has
ribosomes on its
surface & makes
proteins to
EXPORT
http://sps.k12.ar.us/massengale/biology
Golgi Apparatus
Stacks of flattened
sacs
Have a shipping side
& a receiving side
Receive & modify
proteins made by ER
Transport vesicles
with modified
proteins pinch off
the ends
Transport
vesicle
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Lysosome
Contain digestive
enzymes
Break down food
and worn out cell
parts for cells
Programmed for
cell death (lyse &
release enzymes to
break down &
recycle cell parts)
http://sps.k12.ar.us/massengale/biology
Cell Organelles
Vacuole
Plants have a large
central vacuole
Animals several small
vacuoles
Storage
Contains cell sap
Sugars, proteins,
minerals, wastes, &
pigments
http://sps.k12.ar.us/massengale/biology
Plant Cell Organelles
Chloroplast
Contain the green
pigment chlorophyll
Traps sunlight to
make sugars (food)
Process called
photosynthesis
http://sps.k12.ar.us/massengale/biology
Cell Powerhouse
Mitochondrion
( mitochondria )
Rod shape
Site of Cellular
respiration
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In Animal Cells:
Mitochondria
Active cells like
muscles have more
mitochondria
Burn sugars to
produce energy ATP
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Different kinds of plant
cells
Onion Epidermal Cells
Guard Cells
root hair
Root Hair Cell
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vacuole
cytoplasm
nucleus
mitochondrion
glycogen
granule
cell
membrane
http://sps.k12.ar.us/massengale/biology
Animal cell
No cell wall or
chloroplast
Stores glycogen
in the
cytoplasm for
food energy
Different kinds of animal
cells
white blood cell
Amoeba
red blood cell
muscle cell
cheek cells
http://sps.k12.ar.us/massengale/biology
sperm
nerve cell
Paramecium
Similarities between plant
cells and animal cells
Both have a cell membrane
surrounding the cytoplasm
Both have a nucleus
Both contain mitochondria
http://sps.k12.ar.us/massengale/biology
Differences between plant
cells and animal cells
Animal cells
Plant cells
Relatively
smaller in size
Relatively
larger in size
Irregular shape
Regular shape
No cell wall
Cell wall present
http://sps.k12.ar.us/massengale/biology
Differences between Plant
Cells and Animal Cells
Animal cells
Plant cells
Vacuole small or
absent
Large central
vacuole
Glycogen as food
storage
Starch as food
storage
Nucleus at the
center
Nucleus near cell
wall
http://sps.k12.ar.us/massengale/biology
Structure and Support
Cytoskeleton –
Support structure,
Rods and filaments
Constantly changing
Microtubules –
Thin hollow cylinders
Made of proteins
Microfilaments Thin, solid protein fibers
Movement of the Cell
Flagella – long
projections that
propel the cell
with whip like
motions
Cilia – hair like
projections that
wave
http://www.surrey.ac.uk
Cell Analogy Model – 100 pts
Title/Communication:/10pts
Creativity/Originality/Neatness/10
pts
Use of Color and in 3D/10 pts
Communication of ideas with
Appropriate Analogies
/ 5 pts ea
Total of 12/60 pts
Total/100 pts