UNIT 2 SEC 7.3Homeostasis and Transport

CELL WALL

A. Structure Composed of cellulose (__________)

Cellulose is a polysaccharide composed of smaller units called _______________ (glucose)

Glucose protects and supports cell

CELL MEMBRANE

Cell Membrane: Controls what enter and leave cell through

selective permeability Boundary of every cell

CELL MEMBRANE

A. Membrane Lipids Phospholipid bilayer:

Polar hydrophilic head Nonpolar hydrophobic tail

Steriods: Cholesterol provides strength and stability in

movement

CELL MEMBRANE

CELL MEMBRANE

B. Membrane Proteins Integral proteins: embedded in lipid bilayer &

extend from interior exterior of CM

FLUID MOSAIC MODEL

Phospholipid bilayer acts more like a fluid than a solid

II. PASSIVE TRANSPORT

Passive Transport: the movement of substances across the cell membrane without the use of energy

TYPES OF PASSIVE TRANSPORT

Diffusion Osmosis Facilitated Diffusion

A. DIFFUSION

Diffusion: movement of molecules from an area of _______ concentration to an area of ________________

Molecules that use Diffusion:1. _________________2. _________________3. _________________ Cool Science Trick

A. DIFFUSION

Equilibrium: concentration of substances in an area is _______

B. OSMOSIS

Osmosis: diffusion of ________ molecules across CM from area of _______ concentration to an area of ________ concentration

WHO GETS IT?

1) What is diffusion?2) What is equilibrium?3) What is osmosis?

B. OSMOSIS

Direction of Osmosis: Hypotonic: Concentration of solute is lower

outside the cell Hypertonic: Concentration of solute is higher

outside the cell Isotonic: solutes in and outside the cell are equal

B. OSMOSIS

How cells deal w/ Osmosis: Hypotonic Environment: Plant root cells like this

Cytolysis: Hypertonic Environment.:

Plasmolysis:

C. FACILITATED DIFFUSION

Facilitated Diffusion: substances require a ____________ for transport b/c it cannot diffuse through membrane

Molecules that use Facilitation Diffusion1. ________________2. ________________3. ________________

D. FACILITATED DIFFUSION

Protein Channel: pathway for specific ion to pass through cell membrane

III. ACTIVE TRANSPORT (AT)

1) AT: movement of materials from a area of ______ concentration to a _______ concentration using energy

2) Commonly used fora) _________________b) _________________c) _________________

III. ACTIVE TRANSPORT

3) Bulk Transport:Used to transport macromolecules or a

large quantity of substanceA) Endocytosis: a cell will engulf external substances into cell

-2 Types 1) Pinocytosis: cell ___________2) Phagocytosis: cell __________

ENDOCYTOSIS AND EXOCYTOSIS

III. ACTIVE TRANSPORT

B) Exocytosis: process to remove materials from cell