C' Proteins

1

C. Proteins 1. Structure 2.
Functions a. energy storage b. structure c.
metabolic - enzymes d. transport e. immunity
1 - Higher Levels of Structure
2
LE 5-20a
Amino end
Amino acid subunits
Primary Structure the AA sequence
Carboxyl end
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LE 5-20b
Secondary Structure Helices and Sheets
b pleated sheet
Amino acid subunits
? helix
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LE 5-20c
The spiral strands (capture strands) are elastic,
stretching in response to wind, rain, and the
touch of insects.
Abdominal glands of the spider secrete
silk fibers that form the web.
The radiating strands, made of dry silk
fibers, maintain the shape of the web.
Spider silk a structural protein Containing b
pleated sheets
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LE 5-20d
Tertiary Structure Folded / "Globular"
Hydrophobic interactions and van der
Waals interactions
Polypeptide backbone
Hydrogen bond
Disulfide bridge
Ionic bond
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LE 5-20e
Quaternary Structure gt 1 protein bond together
Polypeptide chain
b Chains
Iron
Heme
a Chains Hemoglobin
Polypeptide chain
Collagen
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Atoms and Bonds I. Atoms II. Bonds III.
Biologically Important Molecules A. Water
B. Carbohydrates C. Proteins D. Lipids
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D. Lipids 1. Structure monomer fatty
acid Mammal, bird, reptile fats - saturated -
solid at room temp Plants, fish - often
unsaturated - liquid at room temp. Unsaturated
fats can be 'hydrogenated' (peanut butter)
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D. Lipids 1. Structure monomer fatty acid
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D. Lipids 1. Structure transfats associated
with atherosclerosis
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LE 5-11a
D. Lipids 1. Structure - glycerol... and
binding
Fatty acid (palmitic acid)
Glycerol
Dehydration reaction in the synthesis of a fat
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D. Lipids 1. Structure polymer fat
(triglyceride)
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D. Lipids 1. Structure polymer fat
(triglyceride) phospholipid
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D. Lipids 1. Structure 2. Function
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D. Lipids 1. Structure 2. Function a.
energy storage - long term - densely packed bonds
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D. Lipids 1. Structure 2. Function a.
energy storage - long term - densely packed
bonds b. Cell membranes
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D. Lipids 1. Structure 2. Function a.
energy storage - long term - densely packed
bonds b. Cell membranes c. insulation
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D. Lipids 1. Structure 2. Function a.
energy storage - long term - densely packed
bonds b. Cell membranes c. insulation d.
homones and cholesterol derivatives
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Atoms and Bonds I. Atoms II. Bonds III.
Biologically Important Molecules A. Water
B. Carbohydrates C. Proteins D. Lipids
E. Nucleic Acids (later)
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CELL BIOLOGY - Overview Material/Energy is
absorbed across the membrane (life is cellular)
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CELL BIOLOGY - Overview Material/Energy is
absorbed across the membrane (life is cellular)
It is metabolized - energy and products are
harvested. (metabolism)
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CELL BIOLOGY - Overview Material/Energy is
absorbed across the membrane (life is cellular)
It is metabolized - energy and products are
harvested. (metabolism) The energy (and some
products of digestion) are used to
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CELL BIOLOGY - Overview Material/Energy is
absorbed across the membrane (life is cellular)
It is metabolized - energy and products are
harvested. (metabolism) The energy (and some
products of digestion) are used to 1) build
proteins (growth) which allow response.
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CELL BIOLOGY - Overview Material/Energy is
absorbed across the membrane (life is cellular)
It is metabolized - energy and products are
harvested. (metabolism) The energy (and some
products of digestion) are used to 1) build
proteins (growth) which allow response. 2)
replicate DNA and divide (cell division and
reproduction)
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CELL BIOLOGY - Overview Material/Energy is
absorbed across the membrane (life is cellular)
It is metabolized - energy and products are
harvested. (metabolism) The energy (and some
products of digestion) are used to 1) build
proteins (growth) which allow response. 2)
replicate DNA and divide (cell division and
reproduction) Which produces patterns of genetic
relatedness among cells and organisms
(evolutionary history)
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CELL BIOLOGY - Overview A. Membranes - how
stuff get in/out of cells 1. Structure
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LE 7-2
CELL BIOLOGY - Overview A. Membranes - how
stuff get in/out of cells 1. Structure -
phospholipids
WATER
Hydrophilic head
Hydrophobic tail
WATER
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LE 7-5
Lateral movement (107 times per second)
Flip-flop ( once per month)
Movement of phospholipids
Viscous
Fluid
Unsaturated hydrocarbon tails with kinks
Saturated hydro- carbon tails
Membrane fluidity
Cholesterol
Cholesterol within the animal cell membrane
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LE 7-7
Fibers of extracellular matrix (ECM)
Glycoprotein
Carbohydrates
Glycolipid
EXTRACELLULAR SIDE OF MEMBRANE
Cholesterol
Microfilaments of cytoskeleton
proteins
CYTOPLASMIC SIDE OF MEMBRANE
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CELL BIOLOGY - Overview A. Membranes - how
stuff get in/out of cells 1. Structure 2.
Functions
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LE 7-9a
Signal
Enzymes
Receptor
ATP
Transport
Enzymatic activity
Signal transduction
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LE 7-9b
Glyco- protein
Attachment to the cytoskeleton and
extra- cellular matrix (ECM)
Cell-cell recognition
Intercellular joining
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CELL BIOLOGY - Overview A. Membranes - how
stuff get in/out of cells 1. Structure 2.
Functions Types of "transport"
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LE 7-11a
Types of "transport" - DIFFUSION
Molecules of dye
Membrane (cross section)
WATER
Net diffusion
Net diffusion
Equilibrium
Diffusion of one solute
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LE 7-11b
Types of "transport" - DIFFUSION
Net diffusion
Net diffusion
Equilibrium
Net diffusion
Net diffusion
Equilibrium
Diffusion of two solutes
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LE 7-12
Lower concentration of solute (sugar)
Higher concentration of sugar
Same concentration of sugar
H2O
Selectively permeable mem- brane sugar
mole- cules cannot pass through pores, but water
molecules can
- OSMOSIS diffusion of water across a
semi-permeable membrane from HI to LO water
potential
Water Potential as solute conc.
increases as pressure increases
Osmosis