worksheet 3b, due Tuesday 9-22-09

Chapter 3b, Membrane transport, worksheet/outline (page 63-70)
Directions: Read the chapter. As you are reading, take notes on the following questions and vocabulary words. You may also have notes or explanations of many of these in class. Please read for more than just the answers to this worksheet as additional details can give examples or make things more clear.

Membrane transport
Permeability
Impermeable
Selectively permeable
Freely permeable
Whether or not a substance can cross a membrane is determined by:
1.
2.
3.
4.

Passive process
Active process

Diffusion
Concentration gradient
Carbon dioxide example:
Diffusion across membranes depends on:
1.
2.
Examples of things that can pass through the membrane

Channels are usually very small, 0.8nm in diameter so ___________, and ____________ can pass through but larger molecules like _____________ can not.

Osmosis –
Solutes –
Dilution
Osmosis is the diffusion of water across a membrane, from a area of high concentration to an area of lower concentration. This dilutes the solutes until the concentration is the same on both sides of the membrane.
Isotonic –
Hypotonic –
Homeolysis –
Hypertonic –
Crenation –

Filtration –


Carrier mediated transport –
Facilitated diffusion –
Receptor site
Active transport –
Ion pumps –
Exchange pump –
Sodium-potassium exchange pump –

Vesicular transport –
Endocytosis –
Receptor mediated endocytosis
Pinocytosis
Phagocytosis

Exocytosis –

Answer the concept check questions on page 70 (in your own words)
Then check your answers in the back of the book.