Transcript Cell Structure & Function

Cell Structure
& Function
EQ: Why is each part of the
cell essential for survival
http://koning.ecsu.ctstateu.edu/cell/cell.html
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.
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
•Eukaryotic
Prokaryotic
• Do not have
structures
surrounded by
membranes
• Few internal
structures
• One-celled
organisms,
Bacteria
http://library.thinkquest.org/C004535/prokaryotic_cells.html
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
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
• The “control center” of the cell
Nucleus
• Means “kernel” or “nut”
• Is covered by a membrane which allows
materials to pass.
• Is the control center of the cell
• Stores DNA (Which makes protein)
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
DNA
• Made of _________
• Contain
instructions for
traits &
characteristics
http://library.thinkquest.org/12413/structures.html
Cytoplasm
• Gel-like mixture (cytosol)
• Surrounded by cell
membrane
• The “environment” of the
cell.
Quick Write:
How do
these
images
relate to the
cytoplasm of
a cell?
Cytoplasm
Organelles
Cytoplasm
Mitochondria
• Produces
energy
through
chemical
reactions –
breaking down
Lipids &
carbohydrates
http://library.thinkquest.org/12413/structures.html
Mitochondria
• The cells “power plant”
• Food molecules are
broken down in the cell to
release energy.
• Bean shaped
• 2 membranes
• Work only with oxygen
Outer and Inner
Membranes
Chloroplast
• Usually found
in plant cells
• Contains green
chlorophyll
• Where
photosynthesis
takes place
http://library.thinkquest.org/12413/structures.html
Chloroplasts
•
•
•
•
•
Only in plants, Euglena, and algae
Energy-converting from the sun
2 membranes
Looks like stacked coins
Contain Chlorophyll (green) which traps light
and makes it into sugar (photosynthesis)
Chloroplasts
&
Mitochondria
• Theory that they evolved from ancient bacteria.
• Created by cells eating each other.
• Have the same kind of ribosomes and circular
DNA.
&
=
Ancient
Bacteria
Bull’s-Eye Comparison:
Mitochondria vs. Chloroplast
Mitochondria
Chloroplast
Similarities
Explain how
your illustration
and similarities
are connected.
Differences
Differences
Illustration
depicting how
they relate
Endoplasmic Reticulum
http://library.thinkquest.org/12413/structures.html
• Moves materials
around in cell
• Smooth type:
lacks ribosomes
• Rough type
(pictured):
ribosomes
embedded in
surface
Ribosomes
• Each cell
contains
thousands
• Make proteins
• Found on
ribosomes &
floating
throughout the
cell
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
http://library.thinkquest.org/12413/structures.html
Vacuoles
• Membranebound sacs for
storage,
digestion, and
waste removal
• Contains water
solution
• Help plants
maintain shape
http://library.thinkquest.org/12413/structures.html
The Hierarchy of
Life
The Hierarchy of Life
Hierarchy – (noun)
1: a series of ordered
groupings of people
or things within a
system
Cell
smallest
largest
Tissue
Organ
Organ System
Organism
A system
is a combination of parts or objects
performing a complex function.
The smallest unit of structure
performing functions in organisms is
the
cell
.
Many specialized cells working together to perform a
particular function form
tissues
.
A group of tissues working together to perform
a specific function form
organs.
A group of organs working together to
perform a complex function is an
organ system
.
Organ systems working together form
organisms.
Levels of
organization
in multicellular
organisms.