Transcript Cells - Model High School

Cells
I. Basic History
_______
Every
living thing,
from the tiniest
bacterium to the
largest whale,
are made of one or more cells!
Before the seventeenth century,
CELLS existed.
no one knew that _______
I. Basic History
small to be
cells are too _______
seen with the _____________.
unaided eye
Not discovered until after the
invention of the ____________
microscope in
the early 17th century.
Most
II. Important Scientists
A
Dutch drapery storeowner
________________________,
Anton von Leeuwenhoek became
the _______
FIRST person to _________
OBSERVE
and __________
DESCRIBE
MICROSCOPIC
ORGANISMS and
LIVING
CELLS.
II. Important Scientists
1665:
the English scientist
Robert
Hooke used a
_______________
microscope to examine a
thin slice of ______
cork and described it as
consisting of “a great many little
boxes”. It was after his observation
that Hooke called what he saw
“_______”.
They looked like “little
cells
boxes” and reminded him of the small
rooms in which monks lived. So he
called them “_______”.
cells
Illustration of Cork
drawn by Robert Hooke
II. Important Scientists
1824:
the French scientist
Henri Dutrochet, concluded
that ______
plant and ________
animal
tissue were always made
up of cells.
1831:
Robert Brown
named the _________
nucleus
II. Important Scientists
1838:
German botanist
Matthias Schleiden
concluded that all
________
plants are made of cells.
1839:
German zoologist
Theodor Schwann
animals
reported that _________
are also made of cells.
II. Important Scientists
1845:
Felix Dujardin studied
the living cell and noted it
contained a material called
_____________.
protoplasm
1855:
German physician
Rudolf Virchow induced
that ALL cells come from
preexisting cells.
_____________
II. Important Scientists
The
COMBINED work of Schleiden,
Schwann, and Virchow makeup what
is now known as the modern
_____________.
cell theory
1.
2.
3.
III. The Cell Theory Consists
of 3 Principles
All living things are ____________
composed of
one or more _______.
cells
Cells are the basic units of
_______
___________
structure and __________
function in an
organism.
Cells come ______
ONLYfrom the
_______________
existing cells.
reproduction of __________
IV. Two Types of Cells
1.
EUKARYOTE
_______________
= cell that
contains a _________
other
nucleus and _______
___________
____________________
membrane-bound
organelles
Ex: ________,
plants fish,
mammals, _________
insects
and humans
________
IV. Two Types of Cells
1.
PROKARYOTE = cell that
_______________
_______
_____
lacks a _________
nucleus and other
___________________
__________.
membrane-bound organelles
unicellular
Ex: _____________
organisms such as
bacteria and
__________
their relatives
V. Cell Diversity
o Not
all cells are _______.
alike
o Cells within the same organism
show enormous diversity in ____,
size
______,
shape and ____________________.
internal organization
o Your body contains at least
200 different cell types!
_____
VI. Cell Size:
oA
few types of cells are
large enough to be seen
by the _________
unaided eye.
Female egg is the _________
o _______________
largest cell
in the body and can be seen
without the aid of a microscope.
o Most
cells are visible only with a
____________.
microscope
VI. Cell Size:
Most cells are small for 2 reasons
o ________________________________:
RATIO
Cells are limited in size by the _______
outer surface area
between their _____________________
and their volume
________.
1.
•
•
As a cell’s size increases, its volume
increases much faster than its surface
area.
(see picture on the next slide!)
VI. Cell Size:
2.
The cell’s nucleus (the brain) can
only control a certain amount of
living, active cytoplasm.
VII. Cell Shape:
Variety
o _________
of shapes
o The _______
shape
of the cell
depends on
the __________.
function
VII. Cell Shape:
Nerve cells that
____________
carry information
from your toes to
your brain are long
and threadlike.
Blood cells
o Ex: ____________
are shaped like
round discs that
can squeeze through
tiny blood vessels.
o Ex:
VIII: Cellular Organization
Multicellular organisms
o _______________________
are
made up of many cells, each of
which is specialized to perform a
distinct function.
o
Digestion, movement, respiration, filtering,
etc.
Individual cells
o __________________
DO NOT carry
out ALL life functions, but rather
depend on each other.
VIII: Cellular Organization
o ________
Tissue
= a group of cells functioning
together to perform an activity.
o
o
Ex: muscle and nerve tissues
Ex: Plant tissues = stem and root
o Organs
________
= groups of two or more
tissues that function together.
o
o
Stomach, leaf of a plant
Cooperation among organs makes life
functions within an organism efficient.
VIII: Cellular Organization
o ________
Tissue
= a group of cells functioning
together to perform an activity.
o
o
Ex: muscle and nerve tissues
Ex: Plant tissues = stem and root
o Organs
________
= groups of two or more
tissues that function together.
o
o
Stomach, leaf of a plant
Cooperation among organs makes life
functions within an organism efficient.
VIII: Cellular Organization
Summary
Cells

Tissues

Organs
Microscope
Basics
Always carry a microscope with
one hand holding the arm and
one had under the base.
What’s my Power?
o
To calculate the power of magnification,
__________
_______ of the
multiply the power
_____________
_______ of the
ocular
lens by the power
____________.
objective
O
Objectives
(4X, 10X, 40X)
O
O
Ocular lens
(10X)
What’s my Power?
o Low
Power
o Ocular lens = 10X
o Objective = 4X
o TOTAL magnification for LOW
40X
power = _________
What’s my Power?
o Medium
Power
o Ocular lens = 10X
o Objective = 10X
o TOTAL magnification for MEDIUM
100X
power = _________
What’s my Power?
o High
Power
o Ocular lens = 10X
o Objective = 40X
o TOTAL magnification for HIGH
400X
power = _________
Comparing Powers of Magnification:
o We
can see better details with
________
HIGHER powers of magnification,
but we can’t see as much of the
image.
Which
of these images would be
higher power of
viewed at a ______________
magnification?
Microscope
Pictures
Compound Light Microscopes
o You
will be using a compound light
microscope in several labs.
o These microscopes have a maximum
magnification of 400X
CANNOT see most of the
o So you __________
organelles like ribosomes, Golgi
bodies, lysosomes, etc.
o More powerful microscopes are
needed (2000X plus)
Common Problem . . . AIR BUBBLES
AIR BUBBLES
AIR BUBBLES
Stained Onion Cells
Can you identify the cell walls?
o Can you identify any other organelles?
o
Stained Cheek Cells
Elodea – Typical Plant Cells
as seen with the light microscope
Animal Cell
Nucleus
Rough ER
Golgi Body
Mitochondria
Chloroplasts
Ribosome
Cytoskeleton
How to Make a Wet-Mount Slide
1. Get a clean slide and cover slip from your teacher.
2. Place ONE drop of water/iodine in the middle of the slide.
Don’t use too much or the water will run off the edge and
make a mess!
3. Place the edge of the cover slip on one side of the
water/iodine drop.
4. Slowly lower the cover slip on top of the drop.
5. Place the slide on the stage and view it first with the LOW
power objective. Once you see the image, you can rotate the
nosepiece to view the slide with the different objectives.
Let’s give it a try . . .
1.
2.
3.
Turn on the microscope and then rotate the
nosepiece to click the LOW power objective into
place.
Place a slide on the stage and secure it using the
stage clips. Use the coarse adjustment knob (large
knob) to get the image into view and then use the
fine adjustment knob (small knob) to make it clearer.
Once you have the image in view, rotate the
nosepiece to view it under different powers. Draw
what you see on a piece of paper.
BE CAREFUL WITH THE LARGEST OBJECTIVE!
Sometimes there is not enough room
and you will not be able to use it!
Organelles
of the Cell
Nucleus
Appearance:
Location:
Function:
Large oval
varies
control
center for all cell
functions
Cytoplasm
Appearance:
clear fluid
Location:
inside the cell
membrane
Function:
suspends
organelles site of
chemical reactions
Nucleolus
Appearance:
Round structure
inside the nucleus
Location:
inside
the nucleus
Function:
Site
of RNA synthesis
Produces ribosomes
Plasma (Cell) Membrane
Appearance:
surrounds cell
Location:
Plant:
in cell wall
Animal: outer layer
Semipermeable
 Composed of lipids & proteins

Function:
controls materials in
and out of the cell
Smooth Endoplasmic Reticulum
Appearance:
mesh
of hollow sheets
Location:
connected to the
nucleus and plasma membrane
Function:
Smooth: produces lipids
Ribosomes
Appearance:
small,
dense granules
Location:
Free in
the cytoplasm; attached
to the rough ER
Function:
Synthesize proteins
Golgi Body
Appearance:
Location:
Flattened sacs
Near the ER
Function:
Temporary storage,
packaging and secretion of
proteins and fats
Produces
lysosomes
Mitochondria
Appearance:
usually bean
shaped with folded membranes
(greater surface area – hence
more energy)
Location: many
mitochondria in a cell
Function:
Powerhouse of the cell
(energy production  ATP)
Vacuoles
 Appearance:
cavities filled with fluid
Location:
 Plant: usually 1 large waterfilled vacuole (maintains structure)
 Animal: many tiny vacuoles
 Function: storage of water, starch fats, etc.
 Two types:
 Contractile
vacuole: removes water and
wastes
 Food vacuole: breaks down food
Water Vacuole
Lysosomes
Appearance:
egg
shaped, membranebound structure
Location: ONLY found
in animal cells
Function: Contain digestive enzymes
that break down molecules

aid in digestion of nutrients

break down destructive cells (bacteria)
Cytoskeleton
Appearance:
network of thin,
fibrous proteins
(microtubules & microfilaments)
Location: entire cell
Function: acts as sort of a scaffold to
provide support for organelles
 helps maintain cell shape
Microfilaments
Appearance:
long, threadlike proteins
Location: a part of
cytoskeleton
Function: associated with
muscle contractions in large
organisms
 associated
with cell movement
Microtubules
Appearance:
thin, hollow
cylinders of proteins
Location: a part of
cytoskeleton
Function: provide shape
and rigidity to the cell
 Assist
organelles to move from
place to place within the cell
Cilia
Appearance:
thin
hair-like projections
Location: formed
from specialized
microtubules
Attached
to outside of cell
Function: aid in
movement and locomotion
(lungs and intestinal cells)
Flagella
Appearance:
whip-like tails
Location: formed
from specialized
microtubules
Attached
to outside of cell
Function: aid in
movement and locomotion (sperm)
Chromatin
Appearance:
strings of “spaghetti”
Location: inside nucleus
Function: uncoiled DNA; involved
in duplicating cells. Coils into
chromosomes
during cell
division.
Chromosomes
Appearance:
coiled chromatin
Location: inside nucleus
Function: contains genetic
information (DNA)
Centrioles
Appearance:
two small structures
Location: found inside the
centrosome (only in animal cells)
Function: moves chromosomes
during cell division
Plastids (plants only)
Appearance:
varies;
have own DNA
Location:
ONLY in plants
Function: based on type:
Leucoplast (store starch),
chromoplast (store pigments),
chloroplast
Chloropast (plants only)
Appearance:
small, circular, green
(contains chlorophyll-green
pigment)
Location:
ONLY in plants
Function:
site of
photosynthesis
Cell Wall (plants only)
Appearance:
made of cellulose;
rigid, strong, stiff structure
Location:
surrounds cell membrane
(ONLY in plants)
Function: support and protection
 Allows
H2O, O2, CO2 to pass into and
out of cell
NOTE:
All
the ____________
organelles work together!
For
example, after some proteins are
made by the ____________,
ribosomes the rough
ER transports these proteins to the
___________________,
Golgi apparatus then the Golgi
makes vesicles that can fuse with the
cell’s plasma membrane to release
proteins to the _______________
environments
outside the cell or used within the
cell.
Microfilaments
Golgi body
Smooth ER
Ribosomes
Nucleolus
*Centrioles
*Lysosome
Mitochondria
Chromatin
Microtubule
Rough ER
Nucleus
Plasma
Membrane
*Vacuole
many small ones
Ribosomes
Microtubule
*Plastid
*Water
Vacuole
Microfilaments
Nucleolus
Mitochondria
Plasma
Membrane
Golgi body
Chromatin
Smooth ER
*Chloroplast
Nucleus
Rough ER
*Cell Wall
Plasma
Membrane
I. Maintaining Balance
How do cells maintain balance
o _______________________________?
o Cells
need to maintain a balance
by controlling material that move
in and out of the cell 
HOMEOSTASIS
_______________.
I. Maintaining Balance
Small
o _______
molecules like water,
oxygen, and carbon dioxide can
move in and out of the cell
freely
_______.
Large molecules like proteins
o _______
and carbohydrates ________
cannot
o ___________________
Eliminating wastes
I. Maintaining Balance
Structure of the
Plasma (Cell) Membrane
o All
cells are surrounded by a
plasma membrane
____________________.
o Functions like a GATE, controlling
what _______
_______ the cell.
ENTERS and LEAVES
o The cell membrane is
semipermeable or
________________
selectively permeable.
Structure of the
Plasma (Cell) Membrane
oA
____________________________
semipermeable membrane
only allows certain molecules to
pass through.
o Some substances
easily cross the
membrane,
while others
cannot cross at all.
Structure of the
Plasma (Cell) Membrane
o Made
of a thin layer of ________
lipids
and __________
proteins
o Made
mostly of
_______________
phospholipid molecules
(Phosphate + Lipid)
o Phospholipids are a kind
of lipid that consists of
2 FATTY ACIDS (_______)
tails and
PHOSPHATE GROUP (_______)
heads
Structure of the
Plasma (Cell) Membrane
o Cell
membranes consist of TWO
phospholipid layers called a
LIPID BILAYER
________________
Structure of the
Plasma (Cell) Membrane
Structure of the
Plasma (Cell) Membrane
o Water
molecules surround ______
both
sides of the cell membrane.
o Polar __________________
phosphate heads sticking
TOWARD the water (____________)
hydrophilic
o Nonpolar __________
lipid tails point AWAY
from the water (______________)
hydrophobic
Structure of the
Plasma (Cell) Membrane
o The
cell membrane is constantly
being formed
_______ and ______________
broken down
in living cells.
III. Lipid Bilayer
o Moving
with and among the
phospholipids are cholesterol,
proteins, and carbohydrates.
o _____________
Cholesterol
o Nonpolar,
found among the
phospholipids to help prevent the
fatty acid tails from __________
sticking
together.
o Helps with structure and homeostasis
III. Lipid Bilayer
III. Lipid Bilayer
o __________:
Protein
Found on the surface of the plasma
membrane = __________
transmit signals to the
inside of cell.
o Embedded in the plasma membrane =
structure and support of cells shape,
move large substances in and
and _______
out of the cell.
o
III. Lipid Bilayer
III. Lipid Bilayer
o _______________:
Carbohydrates
Attached to proteins, helps cells
identify _____________________
chemical signals
o Ex: help disease fighting cells recognize
and attack a potentially harmful cell
o
Cellular
Transport
Cellular Transport
o All
particles move and have
_______
kinetic energy (energy of motion)
o Movement is ________
random and usually
in a ________________
water solution
o
Cells are mostly made of water and there
is a constant flow of ions and particles.
IV. 2 Types of Cellular Transport
1.
2.
___________________
Passive transport =
movement of molecules across
the membrane by using the
molecules _________
kinetic energy.
The cell exerts NO
___ energy!
__________________
Active transport = transport
of materials against the
concentration gradient and
requires _________________.
cellular energy
V. Passive Transport
o3
1.
types of passive transport:
___________
Diffusion = the net movement of
HIGHER
___________
particles from an area of __________
concentration of
particles to an
LOWER
area of _________
concentration of
particles
Diffusion . . .
o Molecules
move __________
randomly until
equally distributed.
they are _________
o Diffusion continues until the
concentration of substances is
uniform throughout.
Diffusion . . .
o _____________________
Dynamic equilibrium
= continual
movement but no overall change
in concentration.
o
Movement of materials
into and out of the cell
at equal rates maintains
its dynamic equilibrium
with its environment.
Diffusion . . .
o Diffusion
depends on the
Concentration gradient
________________________
o
o
__________________________
Concentration gradient is the
difference between the concentration of
a particular molecule in one area and
the concentration in an adjacent area.
Ex. Gas exchange in the lungs (oxygen
from air to blood and carbon dioxide
from blood to air)
V. Passive Transport
2.
Facilitated diffusion
_______________________
= type
of passive transport that
increases the rate of diffusion
with the use of
__________________
carrier proteins
o Ex:
Facilitated diffusion of glucose
Facilitated Diffusion . . .
V. Passive Transport
3.
_________
Osmosis = the diffusion of
water molecules from an area
_______
of HIGH water concentration
to an area of
LOW water
concentration
V. Passive Transport: Osmosis
o Occurs
in response to the
concentration of solutes dissolved
in water!
o Solutes
_________ are dissolved substances in a
solution
water containing
is mostly _______
many dissolved _________.
solutes
o Cytoplasm
V. Passive Transport: Osmosis
o Because
___
no TWO molecules can
occupy the same space at the
same time, the MORE solutes
there are in a
certain volume
of water, the
FEWER water
molecules there can be in the
same volume.
V. Passive Transport: Osmosis
o Plant
and animal cells behave
differently because plant cells
have a large
water vacuole
________
and a
cell wall
__________
V. Passive Transport: Osmosis
o
Ex. Osmosis occurring in a slug (animal) cell
H2O
NaCl
H2O
NaCl
- water leaves the cell
- cells shrivel, slug dies
V. Passive Transport: Osmosis
A.
Isotonic
solution = a solution in
___________________
which the concentration of dissolved
substances (solutes) is the _______
SAME as
the concentration of solutes inside
the cell.
o Osmosis ___________
DOES NOT
occur since a
concentration gradient
is not established!
What happens to
cells when placed in an isotonic solution?
o __________
Plant cell
flaccid (limp)
becomes ________
o
plant wilts because
no net tendency
for water to enter
What happens to
cells when placed in an isotonic solution?
Animal cell
o _____________
- normal
V. Passive Transport: Osmosis
B.
Hypotonic
solution =
_____________________
a solution in which
the concentration
of solute is
LOWER
_________
than the
concentration
of solutes inside
the cell.
What happens to
cells when placed in an hypotonic solution?
Animal cell
o _____________
- water will
move through plasma
membrane into the cell.
This causes the cell to
swell and internal
pressure increase.
o
Cell _______
lyses (bursts)
Drinking too much water
What happens to
cells when placed in an hypotonic solution?
o __________
Plant cell -
normal
The vacuole & cytoplasm
increase in volume
o The cell membrane
is pushed harder against
the cell wall causing it to
stretch a little
o The plant tissue becomes
stiffer (turgid)
o
Why they spray fruit in the grocery store.
V. Passive Transport: Osmosis
B.
Hypertonic
solution =
_____________________
a solution in which
the concentration
of dissolved
substances is
_________
HIGHER than
the concentration
inside the cell.
What happens to
cells when placed in an hypertonic solution?
Animal cell
o _____________
- will
_________
shrivel because
of decreased turgor
pressure
Drinking salt water on a deserted island
What happens to
cells when placed in an hypertonic solution?
Plant cell
o __________
- will lose water
from __________
vacuole and a
decrease in turgor
pressure will occur;
so it is _______________
plasmolyzed
Plants die when salt is spread on icy roads.
What happens to
cells when placed in an hypertonic solution?
Turgor Pressure
o _________________
= internal pressure
of a cell due to water
held there by osmotic
pressure
Plasmolysis = the
o ______________
loss of turgor pressure
causing the plasma
membrane to pull
away from the cell wall
o causes the plant to wilt
Summary of Cell Behavior in Different Environments:
VI. Active Transport
o Movement
of molecules from an
area of ______
LOW to an area of
_______
HIGH concentration (opposite
of passive transport)
o REQUIRES _________________!
cellular energy
o Moves large, complex molecules
such as proteins across the cell
membrane
VI. Active Transport
o Large
molecules, food, or fluid
droplets are packaged in
membrane-bound sacs called
__________.
vesicles
2 Types of Active Transport:
Endocytosis = process by
_____________
which a cell surrounds and
takes in material from its
environment.
1.
•
Used by amoeba to feed and
white blood cells to kill bacteria.
Endocytosis
Outside of Cell
2 Types of Active Transport:
2.
_____________
Exocytosis = expels materials out
of the cell reverse of endocytosis
wastes, mucus &
o Used to remove ____________________
cell products
_______________
o Proteins made by ribosomes in a cell
are packaged into transport vesicles
by the Golgi Apparatus
o Transport vesicles fuse with the cell
membrane and then the proteins are
secreted out of the cell (ex. Insulin)
Exocytosis
Outside of Cell