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August 31, 2015
 TO DO: Notebook, pencil/pen, and your
timeline
 WARM UP: Why do you think
prokaryotes evolve into Eukaryotes?
HOMEWORK:
 Line: distydamaranti
 www.biohs.weebly.com
Cell Theory
 All living organisms are composed of cells
 The cell is the basic unit of life
 Cells arise from pre-existing cells
 Modern Version include
 Energy flow occurs within cells
 Heredity information (DNA) is passed down from cell
to cell
 All cells have the same basic chemical composition
WHAT IS THE
DIFFERENCE BETWEEN A
EUKARYOTE AND A
PROKARYOTE
THE FIRST CELL
 Prokaryotes = The first organism
 Bacteria is a prokaryote
Prokaryote Characteristics
 All prokaryotes have the following:
cell membrane – surrounds and
controls what enters and leaves cell
cytoplasm
ribosomes - makes protein
cell wall
DNA – circular loop found in a region called the nucleoid
Prokaryote Characteristics
 What bacteria don’t have
- nucleus
- membrane bound organelles
Eukaryotes - True Kernal
 Eu = true Karyote = kernal – refers to the nucleus
 Eukaryotes evolved after prokaryotes
prokaryotes appeared 3.8 billion years ago
eukaryotes appeared 1.5 billion years ago
 Types of Eukaryotes – Plants, Animal, Fungi, Protists
Eukaryotes
 Similarities, all eukaryotes have:
 Cell membrane – surrounds
cell controls what enters and
leaves cell
 Cytoplasm
 Nucleus membrane
bound
structure that houses
and protects the DNA
 Linear DNA
 Ribosomes make protein
 Organelles structure within the cell which perform
specialized functions for the cell
example: mitochondria break down
biomolecules to produce
energy (ATP) for the cell
Prokaryotic vs Eukaryotic
 Size 0.3 – 5.0 microns
 Size 10 – 50 microns
Photosynthetic
Bacteria
Chloroplast
Animal cell anatomy
3-11
Plant cell anatomy
3-12
Anatomy of a Protist
Cell Organelles
 Organelle= “little organ”
 Found only inside
eukaryotic cells
 All the stuff in between
the organelles is cytosol
 Everything in a cell
except the nucleus is
cytoplasm
- found in all cells
Cell Membrane
 Boundary of the cell
 Made of a phospholipid bilayer
 Regulates what enters and leaves the cell
Nucleus
 Control center of the cell
 Contains chromatin
- DNA and protein
DNA contains genetic info
 Surrounded by a Nuclear Envelope double layer of membrane
 - contains openings called nuclear
pores which allow materials to pass
into and out of the nucleus
 Nucleolus - makes ribosome parts –
rRNA and protein
Cytoskeleton
 Acts as skeleton and
muscle
 Provides shape and
structure
 Helps move organelles
around the cell
 Made of three types of
filaments – all 3 are
made of protein
Centriole
Aids in cell division
Usually found only in
animal cells
Made of microtubules
Where else have we talked
about microtubules?
Endoplasmic
Reticulum
 A.k.a. “ER”
 Connected to nuclear
membrane
 Highway of the cell
 Rough ER: studded
with ribosomes; it
collects proteins made
by ribosmes
 Smooth ER: no
ribosomes; it makes
lipids – detoxifies
alcohol
Ribosome
 Site of protein
synthesis
 Found attached to
rough ER or floating
free in cytoplasm
 Ribosomes in
cytoplasm can form
groups called
polysomes
That looks familiar…what is a
polypeptide?
Golgi Apparatus
Looks like a stack of
plates
Stores, modifies and
packages proteins
Molecules transported
to and from the Golgi
by means of vesicles
- vesicles are sacks of
membrane which
transport materials
through out the cell
Some vesicles become lysosomes
Some vesicles travel to the cell
membrane where their contents
are excreted
Lysosomes
 Recycling center of
the cell
 Contain digestive
enzymes that break
down worn out cell
parts, large
molecules and
wastes
Which organelles do
lysosomes work with?
Mitochondria
 “Powerhouse of the
cell”
 Cellular respiration
occurs here to release
energy in the form of
ATP for the cell to use
 Bound by a double
membrane
 Has its own loop of
DNA – like bacterial
DNA
Chloroplast
 Found in plant cells and
some protists
 Contains the green
pigment chlorophyll
 Site of photosynthesis
- produces sugar
 double membrane
 contains a loop of DNA
like bacterial DNA
Cell Wall
 Found in plant, fungi
and bacterial cells
 Rigid, protective
barrier
 Located outside of the
cell membrane
 Made of cellulose
(fiber)
Vacuoles
 Large central vacuole found
in many plant cells: contains
water, salt etc..
- forms over time as many
smaller vacuoles fuse together
– can be 80% of cells interior
 Smaller vacuoles found in
animal cells
- food vacuoles – form when
a cell engulfs food
- contractile vacuoles found
in some freshwater protistspump out excess water
What type of microscope may have
been used to take this picture?
Vacuoles in Animal Cells
Movement - Flagella

Flagella – Long hair-like structure – found in some
bacteria, and eukaryotic cells
- most eukaryotes with flagella have a single flagella
- flagella are made of
bundles of
microtubules
Movement - Cilia
 Cilia – Short oar-like structures that can
move the cell or be used to be move other things
- found in animal cells and some protists
- found in our throats to move mucus
Cell Membrane
 Cell membrane is also
called the plasma
membrane.
 Consist of two layers of
phospholipid.
Analogy