Free Energy and Enzymes (Chapter 6)
Outline Growing Old With Molecular Mayhem
Free radicals are molecules with extra electrons.
The "extra" electrons have been stripped from other atoms in the cell.
Free radical are highly reactive and can alter
Energy Inputs, Outputs, and Cellular Work
Cells and Energy Hills
("energy in") reactions require energy input resulting
in products with more energy than the reactants had; for
("energy out") reac
What Are Metabolic Pathways?
pathways form series of reactions that regulate the
concentration of substances within cells by enzyme-mediated
linear and circular sequences.
biosynthetic pathways, small molecules are assembled into
How Do Enzymes Lower Energy Hills?
A. The Active Site
A.1. Enzymes increase the rate of reactions by creating a microenvironment that is
energetically more favorable for the reaction.
A.2. Each enzyme molecule has an active site where the substrate binds
Photosynthesis (Chapter 7 Outline)
Sun, Rain, and Survival
For life based on organic compounds, two questions can be raised:
Where does the carbon come from?
Where does the energy come from to link carbon and other atoms into
But Things Don't Really End With Glucose
light-dependent reactions convert light energy to chemical energy
(which is then stored in ATP); the liberated electrons are picked up by
light-independent reactions assemble sugars and oth
Where Are Photosynthetic Pigments Located?
Photosynthetic pigments are found in bacteria where they are located on
the plasma membrane.
In the thylakoid membrane systems of chloroplasts the pigments are organized
in clusters called photosystems consisting
The Legacy-A New Atmosphere
is a by-product of the noncyclic pathway.
about 1.5 billion years ago, large amounts of oxygen
began accumulating in the atmosphere, which up to that time had
Case Study: A Controlle
January 21, 2014
The gene pool of a population that is not evolving
can be described by the Hardy-Weinberg principle.
Frequencies of alleles and genotypes in a
population will remain constant from generation
to generation, prov