Transcript Plant and Animal Cell

1.1 Studying the
Structure of Cells
The Cell Theory
 The 3 main ideas are
 All living things are made of one or more
cells
 The cell is the basic organizational unit of
life.
 All cells come from pre-existing cells.
What is a Cell?
All living things are made of cells. Our bodies are made
up of between 10 trillion (1013) and 100 trillion (1014)
cells.
A cell is the basic unit of life. Each contains smaller
parts called organelles. These organelles have special
functions that maintain all the life processes of the cell.
nucleus
nucleolus
rough endoplasmic
reticulum
chromatin
smooth endoplasmic
reticulum
ribosomes
(small brown dots)
central vacuole
Golgi apparatus
cytoskeleton
cytoplasm
mitochondrion
cell membrane
chloroplast
cell wall
wall of adjacent cell
Plant Cell
Animal Cell
Cell Wall
 in plant cells, not
animal
 A tough, rigid
structure lying just
outside a plant cell’s
membrane
 Provides support for
the plant cell and
protection for the cell
organelles
Cell Membrane
 Separates the inside of the cell from the
external environment
 Controls the flow of materials into and out
of the cell
Nucleus
 Brain of the cell
 Controls all cell
activities
 Contains nearly all
the cell’s DNA and
with it, the coded
instructions for
making PROTEINS
and other important
molecules
Nuclear membrane
 Surrounds nucleus
 Protects the contents of the nucleus
 Dotted with thousands of nuclear pores, that
allow materials (such as ribosomes) in and out
Inside the nucleus we
see…
 a granular material called…
 CHROMATIN
 Chromatin= DNA + protein
 Usually spread out in nucleus
 During cell division, chromatin clumps
together or condenses…we call this….
 CHROMOSOMES
Chromosomes
 Threadlike structures that contain genetic
information that is passed on from one
generation to the next
Nucleolus
 Small dense region inside the nucleus
 Function: makes ribosomes
Cytoplasm
 jelly-like substance that fills the cell
 includes the cytosol (fluid), the organelles, and
other life-supporting materials, such as sugar
and water
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Endoplasmic reticulum (ER)
 Connected to the
nucleus
 Network of
membrane-covered
channels that
transport materials
made in the cell
 2 types
 Rough ER (has
ribosomes on it)
 Smooth ER (no
ribosomes)
Ribosomes
 Helps to make proteins
 Proteins make up much
of a cell’s structure and
are required for activities
necessary for the cell’s
survival
 Scattered throughout the
cell
 Some float in the
cytoplasm, and others
are attached to the ER
Golgi Body (Apparatus)
 Function: modifies, sorts, and packages proteins and
other materials from the ER for transport out of the
cell
Vesicles
 Membranecovered sacs that
transport
materials inside
the cell and help
these materials
cross the cell
membrane to
enter or exit the
cell
Vacuoles
 Sac-like organelles
 Function: stores
material such as
water, salts, proteins,
and carbohydrates
 Plant cells have a
single, large central
vacuole, whereas
animals may have
several smaller
vacuoles
What is the one thing
all living things need
to eat, breathe,
reproduce, move and
much more?
ENERGY!!!!
Two ways cells get
energy…
 from food molecules
 from the (plants)
Mitochondria (singular:
mitochondrion)
 Convert chemical
energy stored in
glucose into
compounds that are
more convenient for
the cell to use
 Has 2 membranes
 Inner membrane
 Outer membrane
Chloroplasts
 trap energy from the sun to make glucose
 PHOTOSYNTHESIS
 2 membranes
Cytoskeleton
 Helps the cell maintain its
structure and provides “tracks” along which
vesicles and organelles can move
 2 main parts
 Microtubules
 Microfilaments
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