Cell Biology 2B Membrane Transport.notebook

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February 10, 2015

Feb 9-8:05 AM

Membrane Transport

www.studyblue.com

Feb 9-8:16 AM

VesiclesSmall membrane sacs

containing fluid

spherical, found in

eukaryotes

Formed and broken

down easily because

of membrane fluidity-

pinching of membrane

Feb 9-8:24 AM

Endocytosis vs. Exocytosis

used to bring

larger molecules

into the cell that

cannot pass

through

membrane alone

Ex- placenta

vesicles fuse with P.M. to

release digestive

enzymes (secretion) or

waste products

Ex- water removal from

Paramecium

Feb 9-8:12 AM

alevelnotes.com

Feb 9-8:14 AM

Endocytosis

www.biologyexams4u.com

Feb 9-8:38 AM

Exocytosis

learn.genetics.utah.edu

student.societyforscience.org

Cell Biology 2B Membrane Transport.notebook

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February 10, 2015

Feb 9-8:51 AM

Vesicle Movement Within Cells

rER Golgi Apparatus Membrane

Protein secretion

Phospholipids and proteins made (rER)

Vesicles move to P.M. increasing Surface Area!

Feb 9-9:12 AM

academic.brooklyn.cuny.edu

Feb 9-9:14 AM

4 Ways of Movement across Membrane

1. Simple Diffusion

2. Facilitated Diffusion

3. Osmosis

4. Active Transport

Feb 9-9:13 AM

Simple DiffusionParticles spread out -- continuous random motion

High Concentration Low Concentration

Passive = no energy required

Particles move between phospholipids IF

permeability allows

Small Large Nonpolar Polar

Feb 9-9:27 AM

emp.byui.eduprezi.com

Feb 9-9:30 AM

en.wikipedia.org

Cell Biology 2B Membrane Transport.notebook

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February 10, 2015

Feb 9-9:33 AM

Facilitated Diffusion**

ions or molecules pass through CHANNELS within

plasma membrane

walls made of proteins, small diameter, very specific

selectivity (Examples: Mg, Na, K)

Cells are selective in determining which

channels are made

Feb 9-9:38 AM

pixshark.com

Feb 9-9:41 AM

Osmosisnet movement of water in or out of cell

Passive = no energy required

http://www.majordifferences.com/2013/11/difference-between-diffusion-and-osmosis.html#.VNjQ7-bF-So

Occurs in all cells - Although water is polar,

it can still pass through...Why?

Aquaporins*

Feb 9-10:27 AM

www.goldiesroom.org

Feb 9-10:30 AM

encyclopedia.lubopitko-bg.com

Feb 9-10:36 AM

www.studyblue.com

Cell Biology 2B Membrane Transport.notebook

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February 10, 2015

Feb 9-10:37 AM

Active Transport

movement of particles AGAINST concentration

gradient requires ENERGY!

ATP is source used- product of cellular respiration

Cells contain a wide variety of globular "pump"

proteins--Why?

Feb 9-11:00 AM

online.science.psu.edu