Transcript CHAPTER ONE

Warm Up 9-12-2014
LIST THE 8
CHARACTERISTICS OF LIFE
Cell Structure and Function
Notes
Discovery of the Cell:
• Mid 1600’s scientists began using
microscopes to observe living things
• Robert Hooke used microscope to
observe thin slice of cork—dead plant
material
Cork seemed to be made of box-like
chambers—Hooke called cells
• Anton van Leeuwenhoek discovered
living cells in pond water
Cell Theory:
• All living things composed of cells
• Cells are the basic unit of structure
and function in living things
• New cells are produced from
existing cells
Cell and its Environment:
• Organisms made of one cell—
unicellular organisms
Ex: bacteria
• Organisms made of many cells—
multicellular organisms
Ex: plants, animals
• Each cell must be in “balance” with its environment, exchange
food, waste, H2O, CO2, O2 etc.
• Process by which organisms maintain a relatively stable
internal environment—homeostasis
Cell:
• Organisms that do not have a distinct nucleus—
prokaryotic (PRO = NO)
Ex: bacteria
• Organisms with cells that have true nucleus and
organelles—eukaryotic (EU = TRUE)
Ex: plants, animals, fungi
Cell Parts and Their Functions:
Specialized cell parts called organelles—
“little organs”
Cell membrane—determines what goes in
and out of the cell
aka “gate keeper”
Cytoplasm—gel-like medium that holds the
organelles in position
1. Nucleus—control center of the cell
• Double membrane that surrounds the nucleus—
nuclear membrane
• Hereditary information inside the nucleus—
chromatin (DNA)
Structure
Prokaryotic,
Eukaryotic, or
Both?
Plant,
Animal,
or Both
Nucleus
Eukaryotic
Both
General Characteristics and Functions
Control center of the cell. Contains genes that control
cell activities. Contains most of the cell's DNA, which is
stored as chromatin (DNA wrapped in protein).
Small, dense region in the nucleus. Involved in the
synthesis of ribosomes which are important in protein
synthesis. "Little nucleus"
Double membrane, each consisting of a phospholipid
bilayer. Perforated by nuclear pores which allow RNA
molecules to leave the nucleus.
4. Ribosomes—makes proteins
RIBOSOMES
• Tiny, granular organelles located on
_endoplasmic reticulum_____ or
suspended in _cytosol_______. Site of
_protein production_____. All cells (pro
& euk) have ribosomes.
5. Rough Endoplasmic Reticulum (rough ER)—
makes and transports proteins within the cell
• Called rough ER because of the ribosomes
found on its surface
Rough ER
Extensive network continuous with
_nuclear envelope_____. Called
“rough” because it has
_ribosomes___ all along the
membrane. Function of the rough ER is
to _modify & transport
proteins_____. Most of these proteins
are packaged into _vesicles______
(like bubbles or sacs) and shuttled to
the __Golgi apparatus________
6.
Smooth Endoplasmic Reticulum (smooth ER)—
manufactures and transport lipids and other
materials within the cell. Breaks down glycogen,
detoxifies poisons, and stores calcium.
• Called smooth ER because it lacks ribosomes
found on its surface
7. Golgi apparatus—processes and
packages proteins and other substances
produced in the ER
Golgi apparatus
• Flattened, round sacs that look like a sack of
_pancakes_____. Receives, modifies, and
ships products by way of _vesicles____ into
the _cytosol → cell membrane_______
Found in animal cells only:
8. Lysosomes—cleans up the cell and
digests unwanted materials
lysosomes
• Found in _animal__ cells only. Round sacs
containing _enzymes___ that _break down___
and _recycle_____ used cell components. Also
used as defense against _bacteria_____ and
_viruses__
9. Vacuoles—sac-like structures may be used as
storage for _water___, _molecules__, _or wastes.
• Plant cells usually contain a large vacuole
that fills most of the cell—pressure from this
large vacuole helps plants support
themselves
10. Mitochondria—energy source of the
cell (powerhouse – “Mighty mitochondria”)
Double-walled
organelle with inner
folds _to increase
surface area____.
Uses _glucose_____
to manufacture
energy in the form
of _ATP____.
Mitochondria have
their own
_DNA____.
Found in plant cells only:
11. Cell wall—provides support and
protection for cell
• Composed mainly of cellulose (plant starch)—
fiber for our diet
12. Chloroplast—makes glucose using the energy
from the sun (photosynthesis)
CHLOROPLAST
Found in _plant____ cells. Contain _chlorophyll_____
(green pigment) and their own _DNA______.
Chloroplasts harvest energy from the _sun___ to
produce _ATP___ through _photosynthesis___.
13. Centrioles
Found in _animal____ cells
only. Bundles of
_microtubules_______ that
play a role in _cell
division_____
14 Cytoskeleton—network of protein
filaments that helps cell maintain its
shape
Cytoskeleton
Composed of protein fibers
known as _microtubules____
and _microfilaments_______.
Anchor _organelles_____ and
provide _structure_____. Also
provide motility for some cells
in the form of _cilia___ or
_flagella____. More extensive
cytoskeleton found in
_animal___ cells.
Specialized Parts for movement:
1. Cilia (like little hairs)
2. Flagella (like a tail)
Specialized Cells:
Different cells in your body do different jobs. The
structure (how it’s built) of cells matches the
function (what it does).
• Plant Examples:
1. Leaf cell—contains
many chloroplasts
to maximize
photosynthesis
2. Root cell (potato)—
contains many
vacuoles to
maximize water and
starch storage
• Animal Examples:
1. Epithelial cells—have villi to
increase nutrient absorption;
found in the intestines
2. Muscle cells—contain many mitochondria
to produce more energy for movement
3.
Nerve cells—have fibers called dendrites
that allow nerve cells to communicate
with each other
A deeper look into cells…
• Inside of Cell
• Cell Parts Description and Animation
Plant cells vs. Animal Cells
Plant cell
Animal cell
Both