MOVEMENT IN AND OUT OF A CELL CELL MEMBRANE PLASMA MEMBRANE.

MOVEMENT IN AND OUTOF A CELL

CELL MEMBRANEPLASMA MEMBRANE

TYPES OF TRANSPORT

Passive Transport

• “LAZY”

• No energy (ATP) required

• Controlled by the movement of molecules

Active Transport

• “HIGH ENERGY”

• Energy (ATP) Required

• Controlled by the cell

What is DIFFUSION?

Concen-tration gradient

No energy

High to low

http://www.biologycorner.com/bio1/diffusion.html

UntilEquilibriumIs reached

Concentration Gradient

Salt Water

WATER

SALT

Cover on

http://www.indiana.edu/~phys215/lecture/lecnotes/lecgraphics/diffusion2.gif

What is OSMOSIS?

• Diffusion of water• Water moves from

high to lowhttp://ntri.tamuk.edu/class/ryan/passive.html

WATER

Lots of Water Here

Not Lotsof Water Here

http://www.uic.edu/classes/bios/bios100/lectures/osmosis.htm

What is the function of membrane?

• Homeostasis• Controls movement of materials in

and out of cell

Do you remember what organic molecule the membrane is made of?

Lipid

Phosphate head

Lipids: Phospholipids

• Phospholipid Bilayer

FLUID-MOSAIC MODEL

Outside of Cell

Inside of Cell

PASSABLE• Monomers: amino acids,

glucose, glycerol, F.A.• H2O, CO2, O2,

NON-PASSABLE• Polymers: starch, proteins,

triglycerides• charged ions (Na+, Cl-)

What happens when a cell is placed in a solution with the same concentration as

inside the cell?

Normal Red Blood Cells

ISOTONIC SOLUTION•Iso = same•Tonic = water

•The cells stay the same size

What happens when an animal cell is placed in pure water?

HYPOTONIC SOLUTION

•The cells swellSwollen Red Blood Cells

What happens to plants in a hypotonic solution?

Plant cell placed in pure water?

•Will not rupture due to cell wall

•Turgor Pressure

Video

Water Vacuole

Contractile Vacuoles

What happens to an animal cell placed in salt water?

HYPERTONIC SOLULTION

•The cells shrivel upShriveled Red Blood Cells

Plants in a hypertonic Solution

Plant cell placed in salt water?

•Cytoplasm and membrane shrivel up

•Cell wall remains in place

•Plasmolysis

http://www.youtube.com/watch?v=V56Zy7uLFEA

Osmosis in an animal Cell

Osmosis in a Plant Cell

Facilitated Diffusion• Faster with help of a

protein• No chemical reaction• NO ENERGY needed!• Examples: enzymes and

glucose

Facilitated diffusion is very specific

ACTIVE TRANSPORT

What if you need to get molecules to go against diffusion?

Against the concentration gradient

Uses energy to “pump” molecules in (or out)

What if the food is too big to fit through

the cell membrane?

ENDOCYTOSIS

2 TYPES

PHAGOCYTOSIS

• PSEUDOPODS: false-foot• Creates a food vacuole• Pinocytosis: cell drinking, small particles

• Feeding using pseudopodia (Phagocytosis)

You Tube

http://www.youtube.com/watch?v=W6rnhiMxtKU&feature=related

What is needed to digest another cell after it is eaten?

Stores strong digestive enzymes

Lysosomes are created from the Golgi Apparatus.

Golgi Body

http://www.sumanasinc.com/webcontent/animations/content/vesiclebudding.html

EXOCYTOSIS• Cell egestion• Removal of undigested food • Vacuole moves to edge of cytoplasm and opens up• Opposite of endocytosis

What must a cell do with undigested waste?

• Exocytosis