Download Cells are the basic units of life

Cells are the basic units of life
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Two basic types of Cells
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Prokaryotes
Lacks internal structure
 Surrounded by a membrane
 Most of these cells are singled celled organisms
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Eukaryotes
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Has internal structure
Membranes surround internal structures as well as
the cell as a whole
Contains a nucleus
Cell Organelles
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Cells have structures equivalent to organs in
our body, called organelles
Each of these organelles has a specific
structure and function
Each of these organelles are surrounded by a
membrane, isolating it from the rest of the cell
Animal Cell
Plant Cell
Organelle Functions
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Boundaries
Control
Assembly
Transport
Storage
Energy Transformation
Boundaries
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All cells have boundaries which allow
material to enter or exit
Two main types
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Plasma Membrane (Cell Membranes)
Cell Walls- mostly found on plant cells
Plasma Membranes
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Divide interior of a cell from its external
environment very flexible- allows cells to vary in
shape.
Control the movement of materials that enter
and exit the cell
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Allows useful materials in (O2, nutrient) and waste
materials and excess water out
Materials may move directly through the
membrane, others need passageways in order to
move through
Cell Wall
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An additional boundary found outside of the
plasma membrane
Not found in all cells
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Found in plants, fungi, most bacteria and some
protists
Not found in animals
Not nearly as flexible as c.m.
What is made of depends on the organism
Provides protection and support for the cell
Control of Cell Function
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The nucleus of the cell manages all the cell
functions within the cell
Surrounded by its own double membraneNuclear Envelope
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The nuclear envelope has large pores, so material
can move in and out of the nucleus to the rest of
the cell.
The genetic code (DNA) is house in the
Nucleus in the form of chromatin (long strands
of DNA)
The nucleolus is the center of the Nucleus that
produces Ribosomes
Assembly
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A major function of most cells is to make proteins and
other materials
Most of the assembly takes place within the fluid
inside the cell and outside of the nucleus called the
cytoplasm
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Cytoplasm is a clear fluid the makes up about half the
volume of a typical animal cell and give the cell its shape
Enzymes and other proteins are assembled on the
ribosomes that were made in the nucleolus and
shipped out through the pores of the nuclear envelope
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Ribosomes are an organelle even though they don’t have a
membrane surrounding them
Assembly and Transportation:
Endoplasmic Reticulum
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Folded system of membranes found in the
cytoplasm that connect the nuclear membrane
to the cell membrane.
Involved in the assembly of proteins and lipids
Considered to the delivery system of the cell
Two types of Endoplasmic Reticulum
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Smooth ER: no ribosomes- not involved in protein
synthesis
Rough ER: covered with ribosomes- play a role in
protein synthesis.
Storage
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3 main types of storage in the cell
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Golgi Apparatus
Vacuoles
Lysosomes
Store extra materials needed for the cell
Golgi Apparatus
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Closely stacked, flattened membrane sacs
(pancakes)
Newly made proteins and lipids from the ER are
sent here
Sent to the Golgi Apparatus in small,
membrane- bound packages called vesicles
that were pinched off in the ER
Vesicles are distributed to the cell membrane
and other cell organelles, sent outside of the
cell, or stored for later use.
Vacuoles
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Sac of fluid surrounded by a membrane.
Temporarily stores food, enzymes, and other
materials needed by the cell or waste products
such as excess water that will be expelled.
Plant cells will have a large central vacuole
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Takes up much of a plant cell’s volume
Can store ions, nutrients, wastes, and water
Lysosomes
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Organelles that contain digestive enzymes
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Lyse= break apart
Responsible for breaking down excess or worn
out cell parts, food particles, and invading
bacteria or viruses
The membrane surrounding lysomes keeps
keeps these dangerous enzymes inside the
lysosome
Energy Transformers
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Cells require energy to carry out functions.
Mitochondria are membrane-bound organelles
that transform energy for the cell
Break down food molecules and release energy
Energy is stored in other molecules that can
power cell reactions
Currency Exchange
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Food you eat (Carbohydrates, lipids, and
proteins) as currency
Not all parts of your body are able to accept the
same type of energy
The common energy type is ATP
Carbohydrate, lipids, and proteins and it is
traded for ATP which can be used by all of your
body’s cells
There will be a loss of energy for this
conversions
Mitochondria
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Has double membrane surrounding it
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Outer membrane
Inner membrane
Highly folded that increases surface area
 Location of the production of energy storage moleculeCellular Respiration
 Located in Plant and Animal Cells
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Chloroplast
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Plants can’t eat. So they
make their own food
Photosynthesis
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Using sunlight, water, and
carbon dioxide to make
food (sugars) and oxygen