Download Structure and function of the cell

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Smallest unit of life, Discovered by Robert
Hooke 1695
Cell Theory:
1. All living things have cells
2. Cells are the basic unit of life and function
3. Cells only come from
preexisting cells
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Variety of sizes and shapes
Nerve cells shaped like fingers
Most cells are round in shape
Some cells change shape
◦ White blood cells
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The shape of a cell depends on the cell
membrane and it’s
function
Cells are microscopic for the most
part
 Some can be as large as 6ft in giant
algae
 The cell size is limited by the
______________ of the cell membrane
 A cell can only grow so large then it
will burst
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: structures in a cell that
perform a specific function
: these are cells with
membrane-bound organelles and a nucleus
: these are cells that do not
have membrane-bound
organelles or a
nucleus
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It is
: only certain
things may pass through
Forms a
: 2 layers
of lipids like a sandwich
1. Maintains the shape
of the cell and
2.protects it
Fats and proteins are
embedded in the
phosholipid bilayer
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: have two ends on them
that keep water and nutrients inside
Form a bond that is difficult to break
These lipids are vital to the cell’s survival
Acts like a floating layer, constantly changing
shape
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Do 3 things:
1. Hold the membrane together
2. Allow for channels to be made in the
membrane
3. Act as receptors for hormones and other
compounds
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Model of the cell membrane that shows it’s
“dynamic ability”, how it is more like a liquid
than a solid
The patterns of lipids and proteins are always
changing
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Powerhouse of the cell
Transfers energy from ATP to make the cell
function
Has it’s own DNA,most important organelle to
the cell
Muscle cells will have more mitochondria
than other cells
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Most numerous organelle in a cell
Found in both prokaryotes and eukaryotes
They are not covered in a membrane
They synthesize, or create, proteins
Smallest of the organelles
Vital to cell function and reproduction
Found floating in the cytoplasm and on the rough
ER
◦ Proteins made on free-floating ribosomes are used
within the cell; proteins made on rough ER are usually
shipped to the cell membrane or out of the cell
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Known as the ER, System of tubes and channels
“highway” inside of the cell
2 types rough and smooth
Rough ER has ribosomes along the outside of it
Smooth ER lacks ribosomes and is found in
liver cells
The amount of ER in a cell will fluctuate
depending on how active a cell is in the body
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Makes proteins that are shipped to the cell
membrane or out of the cell completely; the
proteins made here are sent to the Golgi
apparatus for packaging and export
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System of membranes within the cell used to
package and ship proteins
“UPS” of the cell
Modifies or changes proteins before they
leave the cell
Allows cells to take proteins and ship them to
other cells to be used
Often located next to the ER
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Small spheres containing enzymes used for
digestion
Also eat up harmful bacteria and cells
Not found in plant cells, only animal cells
In humans, these organelles aid in
development by destroying certain fetal
tissues
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Houses the DNA in the cell
Largest organelle in the cell
Controls all of the functions of the cell
Must divide when cells reproduce
Has it’s own membrane around it
Controls growth, metabolism and genetics of
a cell
Nucleolus: small part inside nucleus that
makes ribosomes
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Found in plant cells
Less flexible than cell membrane
Gives plant cells the ability to stand up and
grow into trees, flowers etc.
Cell wall is thicker than cell membrane
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: Contain digestive enzymes
in plants.
Some plants will store toxins in the vacuoles
that are poisonous, like poison ivy
: contain chlorophyll so that
plants can make food from sunlight
Chlorophyll is usually a shade of green
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Long protein strands found in the cell
Provide support for the cell
Help to maintain the shape of a cell
Help in the movement of chromosomes when
the cell divides
Vital to the survival of the cell, if these
proteins die the cell will loose it’s shape and
die as well
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Assist in movement of the cell
: Hair-like extensions on the
outside of the cell membrane
: whip-like tail on the cell
membrane of cells
Sperm cells use flagella to swim towards the
egg cell
Cilia are found in lung cells to sweep out
debris
Similar cells that are grouped together form
.
 4 main types of tissues: muscle, nervous,
connective and epithelial.
 Organs are a bunch of tissues that work
together to perform a function. Example: the
heart
 Many organs working together are an
: digestive system uses
the stomach, intestines, kidneys etc.
 Organelles
Cells
Tissues
Organs
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Organ systems
Organism
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