What is the
difference between
a prokaryote and a
eukaryote?
Which one does
bacteria belong
to?
Which term do the
animal and plant
cells fall in?
1
WARM-UP #8: Cell Theory Video
http://www.youtube.com/watch?v=KuJqqiATlqw&feature=rel
ated
Who are the
contributing
scientists and what
did they contribute
for the Cell Theory?
CELLS
Cell Structure and
Function I
Cell Theory
• 1. All living things are made of
cells.
• 2. Cells are the basic unit of
structure and function in living
things.
• 3. New cells are produced from
existing cells
Basic Structure of a Cell
6
Introduction to Cells
Cells are the basic units of organisms
Cells can only be observed under
microscope
Basic types of cells:
Animal Cell
Plant Cell
Bacterial Cell
7
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Cell Exploration
• Light Microscopes
– Living organisms can be
seen
– Light limits the resolution
so extremely small things like
proteins and viruses cannot be
observed
Cell Exploration
• High resolution video technology
– Allows scientists to see time elapsed
movies of cells as the grow, divide and
develop.
– http://www.cellsalive.com/mitosis.htm
Cell
Exploration
• Transmission
Electron
Microscopes
(TEMs)
– Can see more detail and
extremely small structures
– Beams of electrons must
pass through ultra-thin sliced
samples therefore no living
things can be seen
Number of Cells
Organisms may be:
• Unicellular –
composed of one cell
• Multicellularcomposed of many
cells that may
organize
11
Cells May be Prokaryotic or
Eukaryotic
 Prokaryotes include bacteria &
lack a nucleus or membrane-bound
structures called organelles
Eukaryotes include most other cells
& have a nucleus and membranebound organelles (plants, fungi, &
animals)
12
Prokaryotes
Nucleoid region
contains the DNA
•Cell membrane &
cell wall
• Contain ribosomes
(no membrane) to
make proteins in
their cytoplasm
13
Eukaryotic Cell
Contain 3 basic cell
structures:
• Nucleus
• Cell Membrane
• Cytoplasm with
organelles
14
Two Main Types of
Eukaryotic Cells
Plant Cell
Animal Cell
15
Organelles
Very small size
Can only be observed under a
microscope
Have specific functions
Found throughout cytoplasm
16
Organelles Found in Cells
Examples of Organelles include:
Endoplasmic reticulum (rough & smooth) –
canals for movement
Golgi Bodies – wrap & export proteins
Nucleolus – makes ribosomes
Lysosomes – digests & gets rid of wastes
Ribosomes – makes proteins
17
Golgi Bodies
• 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
18
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)
19
Nucleolus
•
Cell may have 1 to 3
nucleoli
• Inside nucleus
• Disappears when cell
divides
• Makes ribosomes that
make proteins
20
Smooth & Rough Endoplasmic
Reticulum
Smooth ER lacks
ribosomes &
makes proteins
USED In the cell
Rough ER has
ribosomes on its
surface & makes
proteins to
EXPORT
21
Cell Powerhouse
Mitochondrion
( mitochondria )
Rod shape
Site of Cellular
respiration
22
In Animal Cells:
Mitochondria
Active cells like
muscles have more
mitochondria
Burn sugars to
produce energy ATP
23
Cell or Plasma Membrane
Cell membrane
Living layer
Controls the
movement of
materials into and
out of the cell
Selectively
permeable
24
Cytoplasm of a Cell
Cytoplasm
Jelly-like substance
enclosed by cell
membrane
Provides a medium
for chemical
reactions to take
place
25
Control Organelle
Nucleus
Controls the normal
activities of the cell
Bounded by a
nuclear membrane
Contains chromosomes
26
Plant Cell Organelles
Chloroplast
Contain the green
pigment chlorophyll
Traps sunlight to
make to make
sugars (food)
Process called
photosynthesis
27
Plant Cell
Cell wall
Protect and support
the enclosed
substances
(protoplasm)
Resist entry of
excess water into
the cell
Give shape to the cell
28
Plant Cell Organelles
Vacuole
Have a large central
vacuole
Surrounded by tonoplast
Contains cell sap
Sugars, proteins,
minerals, wastes, &
pigments
29
Different kinds of plant
cells
Onion Epidermal Cells
Guard Cells
root hair
Root Hair Cell
30
vacuole
cytoplasm
nucleus
mitochondrion
glycogen
granule
Animal cell
No cell wall or
chloroplast
Stores glycogen
in the
cytoplasm for
food energy
cell
membrane
31
Animal Cell Organelles
• Near the nucleus
• Paired structures
• Help cell divide
32
Different kinds of animal
cells
white blood cell
Amoeba
red blood cell
muscle cell
cheek cells
sperm
nerve cell
Paramecium
33
Similarities between plant
cells and animal cells
Both have a cell membrane
surrounding the cytoplasm
Both have a nucleus
Both contain mitochondria
34
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
35
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
36
Compound Microscope
• Instrument for
observing small
objects
• Magnify images
up to 2000X
their size
37
Different parts of
a microscope
38
Revolving
nosepiece
Eyepiece
Clip
Body tube
Coarse
adjustment
Fine adjustment
Condenser
Arm
Iris diaphragm
Stage
Objective
Mirror
Condenser
control knob
Base
39