Did you say Cells?
Yes I said Cells!
YAH CELLS!!!!!!!!!!!!!
 All living things have a
cellular organization,
contain similar
chemicals, use energy,
grown and develop,
respond to their
surroundings, and
reproduce.
 These are the 7 major
characteristics of life!
 All organisms are made
of small building blocks
called cells.
 A cell is the basic unit of
structure and function in
an organism.
 Most cells are small,
about 40 human cells
would fit on the dot of
this letter i.
 Some cells are big, the
yolk of a chicken egg is a
single cell.
 The smallest cells are so
tiny that you could fit
over a million of them on
the period at the end of
this sentence.
 Cells are made of
molecules
 Molecules are tiny
particles of matter.
 Molecules are made up
of atoms.
 The atom is the basic
fundamental unit of
matter.
 Atoms are made up of
protons, neutrons and
electrons.
 Organisms can be composed
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of only one cell or many cells.
Unicellular or single celled
organisms include bacteria
the most numerous
organisms on Earth.
Multi-cellular organisms are
composed of many cells.
You are made up of trillions of
cells.
You have specialized cells in
your body that perform
specific functions.
 The most abundant
chemical in cells is water.
 Other chemicals are called
carbohydrates and these
are the energy source for
the cell.
 Two other chemicals are
proteins and lipids which
are the building materials
for cells, much like wood
and bricks are the building
materials of houses.
 Finally nucleic acids are the
genetic material.
 The cells of organisms use
energy to do what living
things must do, such as grow
and repair injured parts.
 Cells are always hard at work.
 Right now your cells are busy
not only with your eyes and
brain but your blood cells are
moving chemicals around
your body.
 White Blood Cells are
pictured to the right!
 The invention of the
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microscope made it possible
for people to discover and
learn about cells.
A microscope is an
instrument that makes small
objects look larger.
A light microscope that has
more than one lens is called a
compound microscope.
The Top 10 Microscope
IMAGES!!!
Cool Microscopic Images
 One of the first people to
observe cells was the
English scientist Robert
Hooke.
 In 1663, Hooke observed
the structure of a thin
slice of cork using a
compound microscope.
 To Hooke the cork
looked like rectangular
rooms, which he called
cells.
 At about the same time
that Robert Hooke made
his discovery, Anton van
Leeuwenhoek also began
to observe tiny objects
with his microscope.
 Leeuwenhoek was a
Dutch scientists and
when he looked at water
from a pond he saw tiny
single celled organisms.
 Observations from Hooke
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and Leeuwenhoek led to
the development of the cell
theory.
The cell theory states:
All living things are
composed of cells.
Cells are the basic unit of
structure and function in
living things.
All cells are produced from
other cells
 Cells contain even
smaller structures inside
of the cell called
organelles.
 Organelles were called
organelles because early
scientists thought they
looked like “inner
organs” kind of like our
heart, kidneys, or brain.
 The Cell Wall is a rigid
layer of nonliving material
that surrounds the cells of
plants and some other
organisms.
 Cell Walls look rectangular
and shape and are only
found in plant cells.
 A plants cell wall helps to
protect and support the
cell. It provides a rigid
support stand for the cell
and also helps keep out
some harmful substances.
 In plant cells the next layer
inward is the cell membrane.
 In animal cells the cell
membrane forms the outside
boundary that separates the
cell from its environment.
 The cell membranes main
function is that it controls
what substances com into and
out of the cell.
 For example it will let food
and oxygen in but keep out
harmful waste products.
 The nucleus is a large oval
structure inside the cell.
 The nucleus is the cell’s
control center that directs
all of the cells activities.
 It’s really the Brain of the
Cell!
 The nucleus does have a
nuclear membrane which is
an inner protection system
for the cell to protect it’s
nucleus.
 Inside the nucleus you
have DNA
(Deoxyribonucleic acid)
This is what helps cells
reproduce and tells them
what they should do and
look like
 This is why you look like
a combination of your
mother and father
because you have DNA
from both of your
parents.
 The region between the
cell membrane and the
nucleus is known as
cytoplasm.
 This is a clear, thick, gellike fluid.
 Many of the cell’s
organelles are found in
the cytoplasm.
 Inside the cytoplasm you
can find rod shaped
structures called
mitochondria.
 Mitochondria are called
the powerhouses of the
cell because they
produce most of the
energy the cell needs to
carry out its functions.
 Muscle cells rely heavily
on mitochondria.
 The endoplasmic
reticulum (ER) looks like
a giant maze of
passageways.
 The endoplasmic
reticulum is responsible
for moving proteins and
other materials from one
part of the cell to
another.
 Attached to the outer
surface of the endoplasmic
reticulum are small grainlike bodies called
ribosomes.
 Ribosomes function as
factories that produce
proteins for the cell.
 From the ribosomes and
endoplasmic reticulum the
proteins are transported to
the golgi apparatus.
 Within the endoplasmic
reticulum you will find a
flattened collection of
sacs and tubes. These
are called Golgi Bodies.
 The Golgi Bodies are like
the cells mailroom. They
receive proteins ,
package them, and
distribute them to
different parts of the cell.
 Only plant cells and
other protist type cells
have chloroplasts.
 The chloroplasts help
capture energy from
sunlight and use it to
produce food for the cell.
 The chloroplasts give
plants their green color.
 They are responsible for
photosynthesis.
 Throughout the cell you
can find large waterfilled sacs floating in the
cytoplasm.
 These sacs are called
vacuoles. Vacuoles store
food and other materials
needed by the cell.
 All plant cells have a
large central vacuole.
 Lysosomes are small
round structures that
contain chemicals that
break down large food
particles smaller ones.
 Lysosomes also break
down old cell parts and
release the substances so
they can be used again
 Cillia are hair like
structures that are found
on bacteria and some
protist cells. They are like a
bunch of tiny ores that are
used for movement
 Flagella is a whip like
structure that some
bacteria and protists cells
have. When they whip
their tail they propel
themselves through the
water.
 Bacterial cells are smaller
than plant or animal
cells.
 Bacterial cells do have a
cell wall and membrane
but they do not have a
nucleus.
 Organisms whose cells
lack a nucleus are called
prokaryotic or the
organsims prokaryotes.
 Animal and Plant cells
both have a nucleus so
we call their cells
eukaryotic or the
organisms eukaryotes.
 Plant Cells are
rectangular in shape due
to their Cell Walls.
 Plant cells have
chloroplasts which
perform photosynthesis.
 Plant cells have a large
central vacuole. This
helps regulate how much
water the plants lets in or
keeps out. It regulates
osmosis!
 Think about every time you
need energy to move your
cells have to actively be
working so that you can
move.
 Think about every time you
breathe in your individual
cells have to take in oxygen
and use it to make energy.
 All of our energy needs are
met by small tiny parts of
our body that we barely
even think of.
 Diffusion is the movement of
molecules from a high
concentration to low
concentration.
 Diffusion does not require
energy use. It’s kind of like
riding your bicycle down hill.
You still get somewhere and you
still move but you don’t have to
use the pedals.
 Diffusion is a type of passive
transport.
 Sometimes protein channels can
help in moving materials into
the cells. They are embedded in
the cell membrane.
 Active transport is the
movement of materials
through a cell membrane
using energy.
 By doing so cells have move
molecules into the cell that
they need but this requires
energy because there is not
a concentration difference.
 This type of transport is
kind of like riding a bicycle
up hill you get to your
destination but it requires
energy to do so.
 Remember that diffusion is
when you have particles move
from high concentration to
low concentration.
 Remember that osmosis is
when you have water move
from high to low
concentrations.
 This is important when plants
regulate their water supplies.
 Red Blood Cells can burst if
they don’t use osmosis
correctly.
 Molecules are always
moving. As they move, the
molecules bump into one
another. The more
molecules there are in an
area, the more collisions
there will be.
 Collisions cause molecules
to push away from one
another.
 Over time, the molecules
of a substance will
continue to spread out.