Download THE CELL

THE CELL
Cell Theory
1) All living organisms are composed of one
or more cells.
2) Cells are the basic living units within
organisms.
3) All cells arise from preexisting cells.
THE CELL
Cell Function
Organism growth, maintenance, repair, and
reproduction.
Types of Cells
Prokaryotic
Pro
= before
karyotic = kernel (nucleus)
Eukaryotic
Eu = true
Fig. 3.16
THE CELL
Cell Properties
1) Separated from the surrounding
environment by membrane.
2) Takes in raw materials and expels wastes.
3) Absorbs energy to power cellular activities.
4) Builds biological molecules.
THE CELL
Regions
Plasma Membrane
Cytoplasmic
Nuclear
Plasma Membrane Region
Purpose
Separation of outside from inside
environment.
Function
Regulates entrance and exit of substances
Regulates cellular response & activity
Cell recognition
Plasma Membrane Region
Structure
Fluid Mosaic Model
1) Flexible “fluid” membrane
2) Filled with protein, lipid, and
carbohydrates.
Plasma Membrane Region
Lipid Bilayer
Phospholipids
Two nonpolar layers forming the barrier
properties of the cell membrane.
Plasma Membrane Region
Lipid Bilayer
Glycolipids
Structure
Phospholipid
Carbohydrate
Purpose
Cell recognition markers
Plasma Membrane Region
Lipid Bilayer
Cholesterol
Purpose
Makes the bilayer less fluid and
stronger in animal cells.
Plasma Membrane Region
Transmembrane Proteins
Receptor
Detect chemical signals to stimulate cell
activity.
Plasma Membrane Region
Transmembrane Proteins
Recognition
Glycoproteins used for cell identification and
cell-to-cell recognition.
Glycoproteins
Plasma Membrane Region
Transmembrane Proteins
Carrier
Utilize ATP to transport water soluble
substances across the cell membrane.
Plasma Membrane Region
Transmembrane Proteins
Channel
Allows water soluble substances to cross the
membrane freely.
Plasma Membrane Region
Transmembrane Proteins
Water Channels (Aquaporin)
Allow movement of water molecules across the
membrane during osmosis
AQUAPORINS
Extracellular fluid
cytoplasm