CELLS
Chapter 7.1
CELL BIOLOGISTS
 Anton
van
Leeuwenhoek Dutch lens maker
who developed
the first simple
microscope
CELL BIOLOGISTS
Robert
Hooke English
scientist
First
coined the word
“cells”
after
looking at
cork.
CELL
BIOLOGISTS
 Matthias
Schleiden German
Botanist who
studied plant
cells
CELL
BIOLOGISTS
 Theodor
Schwann German
Zoologist studied
animal cells
CELL BIOLOGISTS
 Rudolf
Virchow
–German physician
–New cells could
be produced only
from the division
of existing cells
rudolfvirchow.net/
CELL THEORY:
1. All living things are
made of cells
2.
The cell is the basic
unit of structure and
function
3. Cells come from
other cells
TYPES OF CELLS
 Prokaryotic
- cells with no
nucleus or membrane bound
organelles
 very simple
cells
 bacteria, some
blue-green
algae
 Eukaryotic
- cells with a
nucleus and membrane
bound organelles
 complex cells
 animal, plant, fungi,
protist
Unicellular Organisms
 ONE-
celled organisms which
–Grow
–Respond to environment
–Transform energy
–Reproduce
–Ex: Volvox aureus
www.volvoxaureus.com/volvox.htm
Multicellular Organism
 Organisms
made up of MANY cells
– Different kinds of cells are SPECIALIZED
to perform particular functions within the
organism
– Ex: muscles cells, nerve cells, guard cells,
red blood cells…
Typical Cell?
Levels of Organization
 Observed
in Multicellular Organisms
 Cells- of similar type work together to
form
 Tissues- grouped together to form 
 Organs- work together as part of
 Organ System- group of organs working
together to perform a specific function
 Organism- all systems working together
CELL STRUCTURE
Plasma Membrane
 selectively
permeable
 separates cell from its
environment
 composed of lipid bilayer
with embedded proteins
CELL STRUCTURE
Nucleus
surrounded
by nuclear
envelope
 contains genetic
information
(chromosomes),
“brain” of the cell
Nucleolus
Inside
the nucleus
Makes ribosomes
CELL
STRUCTURE
Cytoplasm
 Composed
mostly
of water
 Has salts, sugars,
proteins and other
materials
suspended in it
 Colloid consistency
CELL STRUCTURES
Organelles - Mitochondria
 Powerhouse
of the
cell
 Contains its own DNA
 Can reproduce when cell
energy demands
increase
 Converts glucose to
other energy forms
The Mighty
Chloroplast
 Only
in plant, algae,
and some bacterial
cells
 Convert the sun’s energy to glucose
 Composed of “solar collectors” called
grana
 Contain chlorophyll pigment
Ribosomes
 Protein
manufacturing
site
 Young cells
have many
more than
older cells
Endoplasmic Reticulum
 Network
of tubes
that transport
materials within
the cell and to the
cell surface for
release
 smooth and rough e.r.
Smooth ER
Manufactures
and
transports lipids within
the cell
Rough E.R.
 Rough in appearance due to
presence of ribosomes
 Manufactures and transports
proteins to cell surface for
release
Golgi
Apparatus
Packages
and
processes cellular
materials and prepares
them for shipment
Golgi Apparatus
Lysosome
 Site of cell digestion
 Contains digestive
enzymes
 Called “suicide
sacs”
 Responsible for
cell destruction
Vacuole
 Used
by cells
to store
nutrients,
wastes, and
cellular
products;
water storage
Vesicles
 Used
by cells to
temporarily store
cellular products
(such as
hormones and
enzymes) before
release from the
cell
Centrioles
 Found
only in animal
cells
 Used during cellular
reproduction to help
separate chromosomes
evenly
Cytoskeleton
 Protein
filaments
which act as
scaffolding to
support cellular
components
 Major component of
cilia and flagella
Cilia and Flagella
Structures
used
for locomotion
of organism or
transportation
of materials
 Found
Plastids
only in plant cells
 Used to store plant
materials
 Chromoplasts - color
 Chloroplasts –
chlorophyll
 Leucoplasts – starch
Cell Wall
 Found
in plants, fungi, and some
bacteria
 NOT found in animal cells
 Made of cellulose, chitin or some
other carbohydrate
 Rigid, provide strength, support,
protection
 Like armor for the plant cell