Transcript INTEGUMENTARY SYSTEM - Orange Coast College

CYTOLOGY
THE STUDY OF CELLS STRUCTURE
GENERAL
Cell = Smallest Living Unit
Produced by Cell Division or Fertilization
Surrounded by Interstitial / Extracellular
Fluid
Components:
- Plasma (Cell) Membrane
- Cytoplasm
- Nucleus
THE PLASMA MEMBRANE
Structure
- Phospholipid bilayer
*self-orienting, reseals
*hydrophilic heads (face outward)
*hydrophobic tails (face inward)
- Proteins (floating or anchored)
- Cholesterol (keeps it “fluid”)
THE PLASMA MEMBRANE
Functions:
- Physical Barrier (Selective!)
* Fat-soluble do pass through
* Water-soluble don’t
- Proteins:
* Channels or Carriers (transport)
* Enzymes (chemical reactions)
* Receptor sites (“docking” of molecules)
* Anchors
THE PLASMA MEMBRANE
CYTOPLASM
Material Between Plasma Membrane
& Nucleus
Components
* Cytosol (fluid with solutes)
* Cytoplasmic Organelles
* Inclusions (stored materials)
Site of chemical reactions
NUCLEUS
Organelle
Double Nuclear Membrane with Pores
DNA – Instructions for making proteins
* Chromatin - loose; protein synthesis
* Chromosomes - dense, rod-like; cell
division
Nucleolus
* Assembly of ribosomes
STRUCTURE OF THE
NUCLEUS
CYTOPLASMIC ORGANELLES
 Mitochondria
- ATP synthesis
(cellular energy)
- Self-replicating
- Contains DNA
CYTOPLASMIC ORGANELLES
 Ribosomes
- Site of Protein
Synthesis
- Free or Attached
 Rough Endoplasmic
Reticulum
- Membrane synthesis
- Proteins made for
export
CYTOPLASMIC ORGANELLES
 Smooth ER
- Lipid synthesis
& breakdown
- Detoxification
CYTOPLASMIC ORGANELLES
 Golgi Apparatus
Prepares proteins
for export
Makes lysosomes
Packages material
to add to plasma
membrane
CYTOPLASMIC ORGANELLES
 Lysosomes
- Digestion within the
cell
- Defense
- Recycle worn-out cells
 Peroxisomes
- Detoxify
* Alcohol
* Formaldehyde
* Free Radicals
CYTOPLASMIC ORGANELLES
 Cytoskeleton
- Proteins
- Support & Shape
- Movement
inside cell
 Centrioles
- Form Spindle
- Form base of
cilia & flagella
CYTOPLASMIC ORGANELLES
Cilia – short, numerous, move substances
over free surfaces
Flagella – long, singular, move cell
Microvilli – thin folds of cell membrane,
increase surface area to maximize
absorption
Cytoplasmic Organelles
Proteosomes
- Ring of stacked proteins around
central core
- Break-up undesirable proteins
Vaults
- Ribonucleoprotein (proteins + RNA)
- May be involved in transport between nucleus
& cytoplasm?