Transcript Cell Structure & Function

Agenda: Sept 22nd
• Review for Test (tomorrow)
Study for Cell Test!
Tables
Inside the Cell
– Cell Structure and Function
– Types of Cells
– Cell’s molecules
• Measuring Very Small Volumes with a
Micropipet
– Basics
– Prepare for Lab after test
Cell Structure
& Function
http://koning.ecsu.ctstateu.edu/cell/cell.html
Eurkaryotic Cell (Eukaryote)
Cell Video
Cell Theory
• All living things are made up of cells.
• Cells are the smallest working units of all
living things.
• All cells come from preexisting cells
through cell division.
Links
•
•
•
•
Animation: Center of the cell
Centre of the Cell
Cell Biology Animation
cell structure
Definition of Cell
A cell is the smallest unit that is
capable of performing life
functions.
Examples of Cells
Amoeba Proteus
Plant Stem
Bacteria
Red Blood Cell
Nerve Cell
Two Types of Cells
•Prokaryotic
–Bacteria
•Eukaryotic
–Animal
–Plant
–Yeast (fungus)
Prokaryotic
• Do not have
structures
surrounded by
membranes
• Few internal
structures
• One-celled
organisms,
Bacteria
http://library.thinkquest.org/C004535/prokaryotic_cells.html
Typical Bacterial Cell
Eukaryotic
• Contain organelles surrounded by membranes
• Most living organisms
Plant
http://library.thinkquest.org/C004535/eukaryotic_cells.html
Animal
“Typical” Animal Cell
http://web.jjay.cuny.edu/~acarpi/NSC/images/cell.gif
“Typical” Plant Cell
http://waynesword.palomar.edu/images/plant3.gif
Yeast Cell
Cell Parts
Organelles
Surrounding the Cell
Cell Membrane
• Outer membrane of cell
that controls movement
in and out of the cell
• Double layer
http://library.thinkquest.org/12413/structures.html
Cell Wall
• Most commonly found
in plant cells &
bacteria
• Supports & protects
cells
http://library.thinkquest.org/12413/structures.html
Inside the Cell
Nucleus
• Directs cell activities
• Separated from cytoplasm by nuclear
membrane
• Contains genetic material - DNA
Nuclear Membrane
• Surrounds nucleus
• Made of two layers
• Openings allow
material to enter and
leave nucleus
http://library.thinkquest.org/12413/structures.html
Chromosomes
• In nucleus
• Made of DNA
• Contain instructions
for traits &
characteristics
http://library.thinkquest.org/12413/structures.html
Nucleolus
• Inside nucleus
• Contains RNA to build
proteins
http://library.thinkquest.org/12413/structures.html
Cytoplasm
• Gel-like mixture
• Surrounded by cell membrane
• Contains hereditary material
Endoplasmic Reticulum
• Moves materials around
in cell
• Smooth type: lacks
ribosomes
• Rough type (pictured):
ribosomes embedded in
surface
http://library.thinkquest.org/12413/structures.html
Ribosomes
• Each cell contains
thousands
• Make proteins
• Found on
endoplasmic
reticulum (ER) &
floating throughout
the cell
http://library.thinkquest.org/12413/structures.html
Mitochondria
• Produces energy through
chemical reactions –
breaking down fats &
carbohydrates
• Controls level of water and
other materials in cell
• Recycles and decomposes
proteins, fats, and
carbohydrates
http://library.thinkquest.org/12413/structures.html
Golgi Bodies
• Protein 'packaging
plant'
• Move materials within
the cell
• Move materials out of
the cell
http://library.thinkquest.org/12413/structures.html
Lysosome
• Digestive 'plant' for
proteins, fats, and
carbohydrates
• Transports undigested
material to cell
membrane for removal
• Cell breaks down if
lysosome explodes
http://library.thinkquest.org/12413/structures.html
Vacuoles
• Membrane-bound
sacs for storage,
digestion, and waste
removal
• Contains water
solution
• Help plants maintain
shape
http://library.thinkquest.org/12413/structures.html
Chloroplast
• Usually found in plant
cells
• Contains green
chlorophyll
• Where
photosynthesis takes
place
http://library.thinkquest.org/12413/structures.html
Structure
Membrane- Plants, animals
bound?
or both?
Function
Nucleus
Yes
Both
Houses chromosomes
Smooth
Yes
endoplasmic
reticulum (SER)
Rough
Yes
endoplasmic
reticulum (RER)
Golgi complex Yes
Both
Lipid synthesis
Both
Protein synthesis
Both
Lysosomes
Both
Sorts contents from the ER
and routes them to their
appropriate locations
Contain digestive enzymes
that break down items that
the cell doesn’t need
Storage of water and
nutrients
Yes
Central vacuole Yes
Plants
Chloroplasts
Yes
Plants
Photosynthesis
Mitochondria
Yes
Both
Energy producer - ATP
Aerobic cellular respiration
Structure
Membrane- Plants, animals Function
bound?
or both?
Cell membrane No
Both
Outer boundary of the cell
Ribosomes
No
Both
Protein synthesis
Cytoplasm
No
Both
Liquid portion of the cell
Cell wall
No
Plants
Flagella
No
Animals
(MAYBE)
A rigid layer on the surface of
the cell membrane – Not the
same structure as bacteria!
A “tail”
Cytoskeleton
No
Both
Cilia
No
Only found on
certain types of
cells – not a
standard
structure
A series of fibers that runs
through the cell. Used to
support the shape of the cell,
for reproduction, and for
tracks for other organelles to
move along in the cell
Microscopic “hairs” on the cell
surface
Typical Animal Cell
Human Cell
Typical Plant Cell
Plant Cells
Yeast
Eukaryotic Cell
(Fungus)
Yeast reproduce by budding
Prokaryotic Cells:
Required Structures
Structure
Function
Cell (plasma) membrane
Outer boundary of the cell
Nucleoid
Area where single loop of DNA is
located
Ribosomes
Produces proteins
Cytoplasm
Liquid portion of the cell
Bacteria- Some Optional Structures
Structure
Function
Cell wall
An extra layer (usually made of peptidoglycan) on
the surface of the cell
Flagellum (a)
A “tail”
Capsule
A gooey layer of the surface of the cell
Pili
Microscopic “hairs” on the bacterial cell surface
Plasmid
An extra loop of DNA
Endospores
Bacterial cells can convert themselves to spores
as a survival strategy
Typical Bacterial Cell
Microscopic View of Bacteria
Genome Size
• The total genome size differ quite
considerably in different organisms.
Organism
•
•
•
•
•
•
Bacteria
Yeast
Worm
Fly
Weed
Human
Number of Chromosomes
1
12
6
4
5
23
Genome size in base pairs
~400,000 - ~10,000,000
14,000,000
100,000,000
300,000,000
125,000,000
3,000,000,000
Genes & % of DNA
Organism
The number of
predicted genes
Part of the genome that
encodes proteins (exons)
E.Coli (bacteria)
5000
90%
Yeast
6000
70%
Worm
18,000
27%
Fly
14,000
20%
Weed
25,500
20%
Human
30,000
< 5%