Cell Structure and function
Chapter 4
(in the Rizzo Class Sequence)
Chapter 7 in Prentice Hall
Section Outline
Section 7-1
•
7–1
Life Is Cellular
A.
The Discovery of the Cell
1. Early Microscopes
2. The Cell Theory
B. Exploring the Cell
C. Prokaryotes and Eukaryotes
1. Prokaryotes
2. Eukaryotes
Watch Out!!!!
• Keep a watchful eye out for
website links some can be used
to access labs, animations or
videos hosted online.
Anton van Leeuwenhoek,
Section Outline
1665 - 75 Anton van Leeuwenhoek,
• the person incorrectly given credit
for the invention of the microscope
• studies organisms living in pond
water .
• He calls them "Animalcules."
Section Outline
Robert Hooke
•
•
1665 - looks at cork under a
microscope.
Calls the chambers he see
"cells"
Section Outline
Schleiden and Schawann
1830 - German scientists
summarize the findings of
many scientists and
conclude that all living
organisms are made of
cells .
Section Outline
Rudolf Virchow
1855- Stated, ”All Cells come
from Pre-existing Cells”
Cell Theory
Section Outline
“All organisms are composed of cells”
1. The cell is the structural unit of
life - units smaller than cells are
not alive
2. The cell is the Functional unit of
life
3. Cells arise by division of
preexisting cells - spontaneous
generation does not exist
Section Outline
Cell Theory
3 facts
3 Exceptions
Bacterial Forms
Binary Fission
Prokaryotic and Eukaryotic Cells
Prokaryotic vs
Eukaryotic
Cell membrane
Cytoplasm
Prokaryotic Cell
Cell membrane
Cytoplasm
Nucleus
Eukaryotic Cell
Organelles
Prokaryotic and Eukaryotic Cells
Section 7-1
Cell membrane
Prokaryotes vs
Eukaryotes
Cytoplasm
Prokaryotic Cell
Cell membrane
Cytoplasm
Nucleus
Eukaryotic Cell
Organelles
Venn Diagrams
Prokaryotes
*simpler
**Normally single
celled Bacteria
***NO (lacks)
membrane
organelles
Eukaryotes
Cell membrane
Contain DNA
Cytoplasm
Ribosomes
*Complex
**Forms tissues
***Has Membrane
bound Organelles
EX. Nucleus
Endoplasmic reticulum
Golgi apparatus
Lysosomes
Vacuoles
Mitochondria
Cytoskeleton
Interest Grabber
Section 7-2
Division of Labor
• A cell is made up of many parts with different functions that
work together. Similarly, the parts of a computer work
together to carry out different functions.
• Working with a partner, answer the following questions.
• 1. What are some of the different parts of a computer?
– What are the functions of these computer parts?
• 2. How do the functions of these computer parts
correspond to the functions of certain cell parts?
Nucleus
• Nuclear Double membrane with pores
– Outer membrane continuous with ER
• Chromatin: Single stranded, balled up
chromosomes
• Chromosomes - protein and DNA
complexes
• Nucleolus - involved in the synthesis and
assembly of Ribosomes
Ribosomes
• The "factories" of the cell involved in protein synthesis
• May either be free or bound to
the ER
Endoplasmic Reticulum
an extensive membranous network
continuous with the outer nuclear
membrane
• Smooth ER: lacks Ribosomes and is
involved in membrane lipid synthesis
•
• Rough ER: has Ribosomes and is
involved in secreted protein synthesis
Intracellular circulation
Golgi Who?
apparatus, complex, bodies
• Flattened vesicles in stacks which
receive protein from ER
• Form secretory vesicles to
transport proteins to different parts
of the cell
– (vacuole, Lysosomes, etc) or for
secretion
Animal Vacuole
• major storage for food,
water enzymes and
waste
• Digestive - break down
of macromolecules
• Storage - ions, sugars,
amino acids, toxic waste
• Ex. Contractile vacuole,
food
Lysosomes
• found mostly in animal cells
• contain enzymes for use in the
hydrolysis (breakdown) of
macromolecules (digestion)
– Breaks down
• food
• damaged or Old cell organelles
– Suicide Bags??
– Sun BURN!!!!
– Ex. Peroxisome
Lysosomes
Peroxisome
• Eukaryotic organelle that
degrades fatty acids and amino
acids
• Also degrades the resulting
hydrogen peroxide
Mitochondria
• Found in ALL eukaryotic cells (yes, even
in plant cells)
• Site of aerobic respiration
– sugars + O2 - - > ATP + CO2 + H2O
• Contain DNA which codes for mitochondrial
proteins, Ribosomes, etc.
• Divide by a process similar to binary fission
when cell divides (asexual replication??)
• Enclosed in a double membrane system
Mitochondria
Check your answers:
Plant
Cell
Ribosome
(free)
Smooth endoplasmic
reticulum
Vacuole
Cytoplasm
Chloroplast
Ribosome
(attached)
Cell
Membrane
Nuclear
envelope
Cell wall
Nucleolus
Golgi apparatus
Nucleus
Mitochondrion
Rough endoplasmic reticulum
Plant Cell
Check your answers:
Animal Cell
Ribosome
(attached)
Nucleolus
Nucleus
Cell
Membrane
Nuclear
envelope
Mitochondrion
Smooth
endoplasmic
reticulum
Rough
endoplasmic
reticulum
Centrioles
Golgi apparatus
Vacuole
Ribosome
(free)
Centrosomes and Centrioles
1.
2.
3.
4.
Found only in Animal Cells
The centrosome, also called the
"microtubule organizing center", is an area
in the cell where microtubles are produced.
Within an animal cell centrosome there is a
pair of small organelles, the Centrioles,
each made up of a ring of nine groups of
microtubules.
There are three fused microtubules in each
group. The two Centrioles are arranged
such that one is perpendicular to the other.
Chloroplasts
1. Found only in plant cells
2. Site of photosynthesis
–
conversion of solar energy to chemical energy in
the form of ATP and sugars
3. Contain DNA which codes for chloroplast
proteins, Ribosomes, etc.
4. Divide when plant cell divides
5. Enclosed in a double membrane envelope
that does not envelope into the chloroplast
Chloroplasts
• Thylakoid is a third internal membrane
system
– contains membrane-bound photosynthetic
pigments
– site of photochemistry (the conversion of
light energy to ATP)
– site of O2 generation
• Stroma is soluble portion of chloroplast
– site of CO2 fixation
– site of sugar synthesis (carbon
metabolism)
– site of chloroplast protein synthesis????
Chloroplasts
Chloroplasts
The photosynthesis reactions can be
broken down into two components:
1. The light-dependent reactions (the
"light" reactions) - occur on the
thylakoid membranes
2. The light-independent reactions (the
"dark" reactions) - occur in the
stroma
Chloroplasts
Cytoskeleton
Microfilaments
– solid protein (actin) which is
assembled at one end and
disassembled at the other end
Intermediate filaments - rope-like
fibrous proteins
– provide structural reinforcement
– anchor organelles
– keep nucleus in place
Microtubules - hollow tubes
– maintains cell shape
– anchor organelles
– movement of organelles
– track for motor proteins
Cell Movements
1. internal, referred to as cytoplasmic
streaming AKA CYCLOSIS
Internal movements of organelles are
governed by actin filaments.
These filaments make an area in which
organelles such as chloroplasts can move.
2. external, referred to as motility. (Motile)
Determined by special organelles for
locomotion.
• Pseudpods
• Cilia, 1000s of hairs, being much
shorter
• Flagella, 1-12 hairs
They both have the characteristic 9 + 2
arrangement of microtubules.
Complete the Venn Diagram on
page 9 In Your “CELL PROTFOLIO”
packet.
Animal Cells
__________
Many more
__________
Plant Cells
1__________
2__________
3 __________
4 __________
5 __________
6 __________
7 __________
8 __________
9 __________
__________
__________
Large __________
Venn Diagrams
Animal Cells
Plant Cells
1 Cell membrane
2 Ribosomes
Cell Wall
3 Nucleus
Chloroplasts
4 Endoplasmic reticulum Large Water Vacuole
Many more
5 Golgi apparatus
Vacuoles
6 Lysosomes
Mitochondria
7 Vacuoles
8 Mitochondria
The cell appears
The cell appears
To have more straight
Irregular shaped 9 Cytoskeleton
Edged
“walls”
Centrioles
7–3 Cell
Boundaries
Section
Outline
A. Cell Membrane
B. Cell Walls
C. Diffusion Through Cell Boundaries
Measuring Concentration (ppm)
1. Passive Transport
a. Diffusion
b. Osmosis
Osmotic Pressure
c. Plasmolysis
d. Facilitated Diffusion
2. Active Transport
Molecular Transport
a. Endocytosis
Phagocytosis
Pinocytosis
b. Exocytosis
Section Outline
Cell Wall
Provides support and protection
Found in:
Fungi-chitin
Algae-composed of cellulose
Plants-composed of cellulose
Cellulose (plant starch) is probably the
single most abundant organic molecule in
the biosphere.
Tough carbohydrate fibers
It is the major structural material of plants
Wood = Paper
Corn Kernels
Lettuce (mostly cellulose)
Cell Membrane
• Regulates what enters and
leaves the cell
• Made up of proteins, lipids and
carbohydrate markers.
• Also known as :
– “The Gate Keeper”
– lipid bilayer or Bilipid Layer
– plasma membrane
– Selectively Permeable barrier
Lipid Bilayer to the Fluid
Mosaic
• A model used to conceptualize the cells plasma
membrane
• the membranes are described as a structurally
and functionally asymmetric lipid-bilayer studded
with embedded proteins
• Named so because the phosopholipids shift
position in the membrane almost effortlessly
(fluid),
• (A mosaic is an image made up of many small
images).
– Examples: lipid molecules, various proteins,
carbohydrates, and cholesterol
http://home.earthlink.net/~shalpine/anim/Life/memb.htm
Figure 7-12 The Structure of
the Cell Membrane
Section 7-3
Outside
of cell
Proteins
Carbohydrate
chains
Cell
membrane
Inside
of cell
(cytoplasm)
Protein
channel
Lipid bilayer
Lipid Bilayer to the Fluid
Mosaic
Lipid Bilayer to the Fluid
Mosaic
Concentration
Gradient
• The difference in concentration
between a region of high
concentration and a region of low
concentration
Measuring
Concentration (ppm)



Mass of the solute in a given
volume of solution.
12g/3L = 4g/L
Parts Per _?__
Concentration Gradient
• The graduated difference in
concentration of a solute per unit
distance through a solution.
• high concentration to low
concentration
• HCLC
Transport
• Is the absorption and
circulation within an
organism
Absorption
• The passage of materials
across the cell membrane
and into the cell
Circulation
• The movement of materials
within a cell and/or
throughout an organism
a) Intercellular circulation
*blood circulation
b) intracellular circulation
- within the cell (cyclosis)
Passive Transport
vs.
Active Transport
Passive Transport:
• Mvmt of materials Without
use of energy.
Active Transport
• Mvmt of materials using
of energy.
• With Concentration
Gradient
• HCLC
• Against Concentration
gradient
• LCHC
• Examples:
• Examples:
–
–
–
–
Diffusion
Osmosis
Facilitated Diffusion
Plasmolysis
– Endocytosis
• Phagocytosis
• Pinocytosis
– Exocytosis
• Re: Contractile Vacuole
Do Now
Using you
knowledge of
transport
complete the
concept web
Transport
Passive Transport
• A type of transport in
which materials move
across the cell
membrane without using
energy
• With the concentration
Gradient ( high concentration
to low concentration)
Passive transport
Diffusion
• The movement of particles
from an area of high
concentration to an area of
low concentration
Osmosis
• The diffusion of water across a
semipermeable membrane from
a region of high concentration
to a region of low concentration
• Example of Passive transport
Section 7-3
Osmosis
Osmosis
• Movie
Effects of Osmosis
on Cells
• Isotonic: concentration of solutes is
the same inside and outside the cell
• Hypertonic: Solution has a higher
solute concentration than the cell
• Hypotonic: Solution has a lower
solute concentration than the cell
Osmosis video site
http://www.ccr.buffalo.edu/etomica/app/modules/sites/Osmosis/Background1.html
Facilitated Diffusion
• Movie
Facilitated Diffusion
Glucose
molecules
High
Concentration
Cell
Membrane
Low
Concentration
Protein
channel
Plasmolysis
•Plasmolysis is the loss of water
from the cell by osmosis.
•This can be proven by inducing the
evacuation of water from the water
vacuole by changing the
environmental concentrations….
How? Plasmolysis video site
red blood cells video site
Plasmolysis
Plasmolysis video site
http://www.uic.edu/classes/bios/bios100/lectf03am/plasmolysis.jpg
Plasmolysis
Plasmolysis lab
Active Transport
• A type of transport requiring
energy to move materials
across the cell membrane
(low concentration to high concentration)
http://www.biology4kids.com/files/cell2_activetran.html
Active Transport
Figure 7-19 Active Transport
Section 7-3
Molecule to
be carried
Energy
Molecule
being carried
Active Transport
Sodium-Potassium Pump
Section 7-3
sodium Potassium pump demo site video
Section 7-3
Ultimate in Cell
Communication
Nerve Cells talking to each other
Phagocytosis (Click on me)
Phagocytosis Online
Phagocytosis (Movie)
Exocytosis
Video 4
Active Transport
• video segment.
“That's All Folks”