Primary Secondary Tertiary Quaternary Protein Structure.
Post on 05-Jan-2016
215 Views
Preview:
Transcript
Primary Secondary Tertiary Quaternary
Protein Structure
Energy
Outline
I. Introduction
A. Metabolism
B. Energy defined
II. Laws of Thermodynamics
III. Energy Transfer in Living Systems
A. Chemical Reactions
B. ATP
Metabolism
All the chemical reactions that occur in the cell Capacity to get and use energy to build, store,
break down, and eliminate substances necessary for growth and reproduction– Catabolism: reactions that break down large
molecules into smaller ones e.g. digestion
energy released– Anabolism: reactions that build larger molecules
from small ones e.g. protein built from AA subunitsenergy required
Energy
Definition: the ability to do work, cause change
Energy obtained from some cellular reactions is used for fueling other reactions
Thermodynamics: The study of energy
Laws of Thermodynamics
1st Law: Energy in the universe is constant– Energy can be transferred or transformed but it
cannot be created or destroyed– Also known as the Energy Conservation law– True for a closed system
Heat and Entropy
Heat is energy and can do work (steam engine) Conversion of any form or energy into heat is
not fully reversible, not all heat is usable energy Heat “lost”=energy no longer capable of doing
work Heat is “low quality” energy Unusable heat associated with disorder
(entropy) Energy flows from high quality to low quality
Laws of Thermodynamics
1st Law: Energy in the universe is constant– Energy can be transferred or transformed but it cannot be
created or destroyed– Also known as the Energy Conservation law– True for a closed system
2nd Law: Disorder in the universe is increasing– Entropy: measure of disorder– In a closed system entropy increases
Maintaining Order
Systems tend toward disorder How do you explain order of a cell, or an
organism? Input of energy required to maintain order
Energy Transfer in Living Systems
Each chemical reaction in a cell has reactants and products
2 types of chemical reactions:– Exergonic: energy released meaning reactants
have more energy than products. Occur spontaneously
– Endergonic: energy required meaning reactants have less energy than products
– Sometimes these reactions are coupled
Energy Transfer in Living Systems
Metabolic Pathway: series of chemical reactions– Often have reactants which are complexed into one or more
intermediates before final productsA + B → C → D → E + F
Where A, B are reactants C, D are intermediates E,F products
Specific enzymes required at each step (each arrow)
Chemical equilibrium: recall this occurs when forward and backward reactions occur at the same rate. Concentrations of reactants and products are stable but not necessarily equal
Metabolic Pathway with inhibition (subtraction symbols)
ATP
Adenosine triphosphate Nucleotide based molecule- ribose, adenine,
and 3 phosphate groups Cellular energy, powers cellular work Bonds between phosphate groups can be
broken by hydrolysis ATP + H2O ↔ ADP + Pi (inorganic phosphate) +
energy
Phosphate groups all negative-repulse each other, like a coiled spring
ATP molecule
ATP hydrolysis
top related