UNIT 1 MODULE 3 Flashcards
PATHWAY OF ENERGY
Sun–>plant sugar–>Digestion–>Cells
Cells
the smallest unit that still displays all the properties of life
All cells have
- cytoplasm
- Plasma membrane
- DNA
- Ribosomes
2 major types of cells
Prokaryotic and Eukaryotic
Prokaryotic Cell
Simple, single-celled (unicellular) organism
-lacks a nucleus, or any other membrane bound organelle
(bacteria and archaea)
Eukaryotic Cell
-Nucleus membrane bound organelles
0Membrane bound compartments inside cells with specific functions
Mitochondria
functions: acts as all-purpose energy converters
-harvest energy to be used for cellular functions
structure “Bag within a Bag”
2 areas inside mitochondria
-Intermembrane space
-mitochondrial matrix
Symbiosis
Individuals of two different species live in physical contact, often for mutual benefit
Endosymbiosis Theory
Mitochondria originated from bacterial cell that took up residence inside another cell
Plasma membrane
-Defines boundary of cell
-Determines the nature of its contact w/ environment
-made of PHOSPHOLIPID BILAYER
Basic integrity of plasma membrane
-Phospholipids
-Cholesterol
-Proteins
-Carbohydrates
Passive Transport
-Diffusion (simple or facilitated)
-Osmosis (water only)
Active Transport
Energy Required
Bulk Transport
special vessicles used to move large quantities at the same time
solute
what molecule is being dissolved
solvent
what molecule is dissolved in
Concentration Gradients
Differences in number of molecules solute per mL solvent across a membrane
Osmosis
-Passive transport of water
isotonic solution
-solute concentrations are balanced
-water movement is balanced
HYPOtonic solution
-solute concentrations are lower in the extracellular fluid
-water diffuses into cells
HYPERtonic solutions
-solute concentrations are higher in the extracellular fluid
-water diffuses out of cells
Active Transport
-movement of molecules across the plasma membrane that requires energy
-molecules being pumped against their chemical gradients
Sodium-Potassium Pump
-important active transport example
-creates a charge gradient that helps maintain cell conditions