Transcript Looking Inside Cells

Looking Inside Cells
Plant / Animal / Bacterial
Cell Size
 Most cells range in size between 1 to
100 micrometers
 In 1 meter there are 100,000
micrometers (µm), in 1 mm there are
100 micrometers (µm)
 Most cells are visible only with the aid
of a microscope
Types of Cells
Cell Wall
 Surrounds plant,
bacterial, fungi and
some protist cells
 Function = Used for
support / shape and
protection
 Made of cellulose in
plants/ proteins /
polysaccharides (big
sugar)
 Allows water and
oxygen to pass through
Cell Membrane
 Surrounds all cells
 Has protein pores
 Function = Controls
what substances go
in and out of the
cell
 Made of lipids (fats)
Nucleus
 Not found in bacterial
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cells (prokaryotes)
Found in plant and
animal cells
(eukaryotes)
Located near the
center of the cell
Function = Control
center, directs cell’s
activities, holds genetic
material (DNA)
Has 3 main parts
3 Main Parts of the Nucleus
 Nuclear Membrane
(has pores/controls
what moves in and
out/protects)
 Chromatin
(genetic material or
DNA and proteins,
contains instructions
to life)
 Nucleolus
(makes ribosomes)
Cytoplasm
 Thick, jellylike fluid
 Function = Cushions and protects the
internal organelles, filling the empty
space, and keeping everything in
place.
 Cytoplasmic Streaming (always moving
to move things in the cell)
 Contains Cytoskeleton (support)
Mitochondria
 Many found throughout
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the cell
Jelly bean shaped
Function =
“Powerhouse”- produce
most of the cell’s
energy
Where RESPIRATION
takes place
Have own double
membrane and
DNA/RNA
Endoplasmic Reticulum
 Found coming out of
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the nucleus
Looks like a maze of
passageways
Function = Carries
proteins and other
materials around cell
Rough ER- Ribosomes
attached
Smooth ER- No
Ribosomes attached
Ribosomes
 Found attached to ER
or floating in cytoplasm
 Very small organelles
that contain tRNA
 Function = Help
produce proteins by
reading mRNA
Golgi Bodies or
Apparatus
 Found out in the
cytoplasm
 Look like flattened sacs
and tubes
 Function = Receive and
package proteins etc.
to be shipped around
and out of the cell
 “Blebs” are the bubble
like packages they
create
Vacuoles
 Found in the cytoplasm
 Look like a fluid filled
bubble
 Function = Used as a
storage area for extra
food / water / wastes /
etc.
 Plant cells have a
central vacuole that is
important in
maintaining plant
turgidity
 Some animal cells have
no vacuoles
Lysosomes
 Found floating in the
cytoplasm
 Look small and round
 Contain harsh
chemicals and enzymes
(type of protein)
 Function = Used to
breakdown food and
old cell parts
Chloroplasts
 Not found in animal
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cells or most bacterial
cells
Found in all plant cells
and some protists
Large, green jellybean
structures
Function = Contain
Chlorophyll (green
pigment) that captures
energy from the sun
Where part of
photosynthesis takes
place
Comparing Cells
Bacterial Plant Cell
Animal
Cell
Cell
Cell Wall
Yes
Yes
No
Vacuole
No
Yes
Sometimes
(central No central
vacuole)
Chloroplasts
No
Yes
No
Eukaryote
No
Yes
Yes
(nucleus)
Prokaryote
Yes
No
No
(no nucleus)
Connecting it All
Cells
Tissues
Organ Systems
Organs
Organisms
Cells – basic unit of structure and function
Tissues - groups of cells that perform a common
function
Organs - group of tissues that perform a specific function
Organ System – collection of organs that work together
Organism – a living thing
Specialized Cells