Copyright © 2005 Pearson Prentice Hall, Inc.
Movement of Materials in Living
Organisms • Cell Membrane Structure and Function
• Diffusion and Osmosis
• Active vs. Passive Transport
• Human Respiration
• Kidney Function
Membrane Functions
• Isolates cell from world
• Regulates cell contents (Homeostasis)
• Allows the cell to communicate with
others
• Allows cells to attach to others
Copyright © 2005 Pearson Prentice Hall, Inc.
Plasma
Membrane
• Semi-permeable
• Permeable to:
- Water - Semi
- Gasses
- Lipid soluble
Materials
• Impermeable
- Ions
- Large molecules http://library.tedankara.k12.tr/chemistry/vol1/balances/trans75.jpg
Cell Membrane Components
• Phospholipids
• Cholesterol – Eukaryotic cells
• Glycolipids – Cell cohesion and
recognition
• Glycoproteins – Cell recognition
• Proteins – Integral and peripheral
Cell Membrane Coloring
• Cholesterol = Yellow
• Phospholipids = Light Blue
• Integral protein = Red
• Peripheral protein = Orange
• Sugar of glycolipid / glycoprotein = Green
S.J. Singer and G.L. Nicolson (1972)
Fluid Mosaic Model
http://lamp.tu-graz.ac.at/~hadley/nanoscience/week4/membrane.jpg
Copyright © 2005 Pearson Prentice Hall, Inc.
polar head fatty acid tails glycerol
backbone
CH3 O
O O
CH2 -CH2 -CH2 -CH2
(hydrophobic) (hydrophilic)
C-N-CH2 -CH2 -O-P-O-CH2 O
HC-O-C-
C-O-C-
CH3
H3
H2 CH2 -CH2 -CH2 -CH2 -CH2 -CH2 -CH2 -CH2 -CH2 -CH2 -CH2 -CH2 -CH2 -CH2 -CH2 -CH3
-CH2 -CH2 -CH2 -CH2
CH2 CH2
CH2 CH2
CH2 CH2
CH2 CH3
CH2 -
Phospholipids
phospholipid
hydrophilic heads
hydrophobic tails
hydrophilic heads
extracellular fluid (watery environment)
cytoplasm (watery environment)
bilayer
Copyright © 2005 Pearson Prentice Hall, Inc.
• Eukaryotic cells
• Adds stability
Holds FA together
• Helps with flexibility
Adds space in
membrane
http://courses.cm.utexas.edu/jrobertus/ch339k/overheads-2/ch11_cholesterol.jpg http://www.uic.edu/classes/bios/bios100/lectf03am/cholesterol.jpg
Caribou
• Cell membranes of
the leg different
than rest of body
• Increased
unsaturated fatty
acids
• Kinky fats
http://www.ece.gov.nt.ca/divisions/kindergarten_g12/curriculum/dene%20kede%20curriculum%20document/animals/caribou.htm
Copyright © 2005 Pearson Prentice Hall, Inc.
Glycolipids and Glycoproteins
• Recognition - allow body to recognize itself
Copyright © 2005 Pearson Prentice Hall, Inc.
Glycolipids and Glycoproteins
Copyright © 2005 Pearson Prentice Hall, Inc.
Cohesion- allow cells to bond to other cells
http://lamp.tu-graz.ac.at/~hadley/nanoscience/week4/membrane.jpg
Glycolipids and Glycoproteins
Protein Function Cell
Junctions
Desmosomes
Tight
Junction
Gap Junctions
http://www.mhhe.com/biosci/ap/saladin/saladin3eppt/saladin3eppt/chapt05_lecture_files/frame.htm#slide0050.htm
Waterproof
Bond Cells
Channels
Copyright © 2005 Pearson Prentice Hall, Inc.
Protein Functions • Transport Protein
- Integral protein pathways - active
and passive
Protein Functions • Receptor Protein
- Acted upon by environment
- Signal cell to complete task
-Hormones
-Nerve receptors
Receptor Protein
• Neurotransmitter
bonds
• Opens special
pathway
Copyright © 2005 Pearson Prentice Hall, Inc. http://kin450-neurophysiology.wikispaces.com/Synaptic+Transmission
Cocaine and Receptor
Proteins
• Cocaine blocks
dopamine
uptake
• Dopamine builds
up in neurons
• Euphoria
http://www.humanillnesses.com/Behavioral-
Health-Sel-Vi/Substance-Abuse.html
Mouse Party
Copyright © 2005 Pearson Prentice Hall, Inc.
Movement of Materials Into Cells
• Passive – requires no cellular energy
- Diffusion
- Osmosis
- Facilitated diffusion
• Active – requires energy from the cell
- Active transport
- Phagocyctosis
- Pinocyctosis
- Exocytosis
Copyright © 2005 Pearson Prentice Hall, Inc.
Diffusion – The random
movement of molecules from
high concentration towards low
concentration
.
lipid-soluble molecules
(O2, CO2, H2O) (extracellular fluid)
(cytoplasm)
Simple diffusion Simple Diffusion – Requires no cellular energy
Copyright © 2005 Pearson Prentice Hall, Inc.
Osmosis – The diffusion of water
What does this mean to the cell?
• Cells are permeable to water
• Cells in low water conditions lose water
• Cells in high water conditions gain
water
Cell 75 % water
25 % other
Beaker contains
50% salt water
What
happens ?
Copyright © 2005 Pearson Prentice Hall, Inc.
S
E
M
IP
E
R
M
E
A
B
L
E
M
E
M
B
R
A
N
E
Diffusion- The random movement of molecules from areas
of high concentration to areas of low concentration.
HIGH WATER LOW WATER
CONCENTRATION CONCENTRATION
Copyright © 2005 Pearson Prentice Hall, Inc.
S
E
M
IP
E
R
M
E
A
B
L
E
M
E
M
B
R
A
N
E
Diffusion leads to equilibrium / greatest entropy
EQUAL EQUAL
CONCENTRATION CONCENTRATION
Cell
Shrinks
Copyright © 2005 Pearson Prentice Hall, Inc.
Hypertonic Solution Solution with higher solute concentration
Cell
75 % - Water
25 % - Other
Beaker
65 % - Water
35 % - Salt
Copyright © 2005 Pearson Prentice Hall, Inc.
Hypotonic Solution Solution with lower solute concentration
Cell
75 % - Water
25 % - Other
Beaker
85 % - Water
15 % - Salt
Copyright © 2005 Pearson Prentice Hall, Inc.
Isotonic Solution Two solution with equal solute
concentrations
Cell
75 % - Water
25 % - Other
Beaker
75 % - Water
25 % - Salt
• Sodium Chloride 0.9%I.V
1000ml Bag Loose
Baxters Saline 0.9% 1000
ml, Sodium Chloride, IV
injection, USP will
rehydrate your patients
quickly and effectively.
This sterile, isotonic
saline solution provides
the essential fluid and
electrolytes that many
patients need.
Copyright © 2005 Pearson Prentice Hall, Inc.
Copyright © 2005 Pearson Prentice Hall, Inc.
Facilitated Diffusion
• Diffusion
through a
protein
pathway
• Passive
• Concentration
gradient
Copyright © 2005 Pearson Prentice Hall, Inc.
Active Transport Mechanisms
• Require cellular energy
• Can move materials with or against
concentration gradients
• Often driven with ATP
•Active Transport
•Endocytosis
•Exocytosis
Copyright © 2005 Pearson Prentice Hall, Inc.
Sodium Potassium Pump
Active transport
OUT IN
Copyright © 2005 Pehttp://veganfeminazi.blogspot.com/2007/06/pictures-for-compendium-
review-chapters.htmlarson Prentice Hall, Inc.
Endocytosis - Pinocytosis an Example
(extracellular fluid)
(cytoplasm)
Vesicle containing Extracellular Fluid (Liquid)
(extracellular fluid)
(cytoplasm)
1
nutrients
receptors
coated pit
Receptor-mediated endocytosis
Receptor proteins for specific molecules or complexes of molecules are localized at coated pit sites.
1