NOTES CHAPTER 5 CELL TRANSPORT

PASSIVE TRANSPORT Movement of a substance through a cell’s membrane without use of cell energy (ATP)

THREE MAIN TYPES

1. DIFFUSION

DIFFUSION RANDOM MOVEMENT FROM A HIGH CONCENTRATION TO A LOW CONCENTRATION

Chapter 5 Click below to watch the Visual Concept. Visual Concept Concentration Gradient Section 1 Passive Transport

WILL CONTINUOUSLY OCCUR UNTIL EQUILIBRIUM OCCURS - concentration is EQUAL INSIDE AND OUTSIDE OF THE CELL

Chapter 5 Diffusion Section 1 Passive Transport

3 TERMS TO KNOW 1. SOLUTE: A SUBSTANCE THAT DISSOLVES IN WATER (SUGAR, SALT)

2.SOLVENT: WATER 3. SOLUTION: MIXTURE OF SOLUTES AND SOLVENT

1. DIFFUSION 2. OSMOSIS

OSMOSIS DIFFUSION OF WATER molecules FROM a concentration of HIGH TO LOW Concentration

Chapter 5 Click below to watch the Visual Concept. Visual Concept Osmosis Section 1 Passive Transport

OSMOTIC PRESSURE: INCREASED WATER PRESSURE INSIDE THE CELL THAT RESULTS FROM OSMOSIS ***EFFECTS CAN BE HYPOTONIC, ISOTONIC, OR HYPERTONIC

1. Hypotonic Environment Solute concentration in the environment is lower than in the cell What will happen? –Water will move into the cell, and the cell will BURST! –Plant cells won’t – burst because of – strong cell wall

2. Isotonic Environment Solute concentration in the environment is equal to that inside the cell (equilibrium) Nothing happens! most cells are isotonic

3. Hypertonic Environment solute concentration in the environment is higher than inside the cell What will happen? –Water will move out – of the cell and the –cell will SHRIVEL!

Low solute high water High solute low water Water goes into cell = solute = water NOTHING High solute low water Low solute high water Water leaves the cell

Chapter 5 Click below to watch the Visual Concept. Visual Concept Comparing Hypertonic, Isotonic, and Hypotonic Conditions Section 1 Passive Transport

1. DIFFUSION 2. OSMOSIS 3. FACILITATED DIFFUSION

FACILITATED DIFFUSION TRANSPORT OF SPECIFIC PARTICLES THROUGH PROTEIN CHANNELS IN THE PLASMA MEMBRANE

Membrane is SELECTIVELY PERMEABLE (ONLY ALLOWS CERTAIN SOLUTES IN ) ** Movement is from High to Low

Chapter 5 Facilitated Diffusion Section 1 Passive Transport

ACTIVE TRANSPORT Transports particles through a membrane against the concentration gradient (Low to High) Requires energy –(–(ATP) Three main types

1. PROTON PUMP

PROTON PUMP Protons are pumped through channels in the plasma membranes of mitochondria and chloroplasts to create energy (ATP) is also called chemiosmosis H + CELL

1. PROTON PUMP 2. SODIUM- POTASSIUM PUMP

SODIUM POTASSIUM PUMP Used energy (ATP) to Power transport potassium ions (K + ) into the cell and sodium ions (Na + ) out of the cell For every 2 potassium ion’s going in, three sodium ion’s go out and 1 molecule of ATP is used ALSO HELPS FOOD GET INTO THE CELL

1. PROTON PUMP 2. SODIUM-POTASSIUM PUMP 3. COUPLED CHANNELS

COUPLED CHANNELS Carry the sodium ions back into the cell along with food molecules It’s fast

What if the food molecules going in or out are way too big to fit through the proteins?

Endocytosis Cell engulf the food molecule requires energy (ATP) “Cell eating ”

Chapter 5 Click below to watch the Visual Concept. Visual Concept Endocytosis Section 2 Active Transport

PINOCYTOSIS Same endocytosis, but materials entering the cell are liquids “cell drinking”

PHAGOCYTOSIS Material brought into cell is another cell or other fragment Very common in unicellular organisms example: white blood cells “Cell Cannabalism”

EXOCYTOSIS Reverse endocytosis Dumping of wastes outside a cell by disposing them from vacuoles “Cell Vomiting”

Chapter 5 Click below to watch the Visual Concept. Visual Concept Exocytosis Section 2 Active Transport