Transcript Reznick/Endler Study on Guppies

English Peppered Moth
Example
English Peppered Moth Example
Before industrial revolution After industrial revolution
Galapagos Ground Finch
Study by Rosemary and Peter Grant
In dry years average beak depth increases
-birds with large bills survive better
-more large seeds available
In wet years average beak depth decreases
-birds with small bills survive better
-more small seeds available
Reznick/Endler Study on Guppies
• Guppies in Trinidad (Caribbean)
• Correlated changes in life history
characteristics with type of predator
• Small predator (Killifish) preys on juvenile
guppies
• Large predator (Pike Cichlid) preys on
large sexually mature guppies
• Guppies with cichlids repro at younger age
The Experiment
• Experimental Group: guppies transplanted
from pike cichlid to killifish pools
• Control Group: guppies that remained in
pike cichlid pools
• What happened??
• Experimental Group/transplanted guppies
gained an average of 14% greater mass
Inorganic Chemistry
• Atom, Molecule
• Subatomic Particles:
protons (+), electrons (-), neutrons
• Atomic nucleus: protons + neutrons
• Atomic number = # protons
• Atomic Weight = # protons + # neutrons
• # Protons = # Electrons
Isotopes
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Differ in number of neutrons
12C
6p 6n 6e14C
6p ?n 6e14C
6p 8n 6eIsotopes are radioactive
Can be used as tracers
Can date materials
Dangers of Isotopes?
• 1986 Chernobyl
• 1979 Three Mile Island
• Strontium?
Energy
• Capacity to do work
• Potential vs. Kinetic
• Different states of potential energy for
electrons
• Electron arrangement in outer shell
• 3 Main Bonds: Ionic, Covalent, Hydrogen
Ionic Bond: Transfer of electrons
Covalent
Bonds:
Sharing of
electrons
Hydrogen Bond: weak bond between a polar bonded
hydrogen and a polar bonded oxygen or nitrogen
WATER: polar covalent and
hydrogen bonds
Properties of Water: Cohesion and Adhesion
Cohesion: holds water together within a vessel
Adhesion: water sticks to vessel wall resisting gravity
High Surface Tension
Properties of water:
(Due to hydrogen bonding)
• Cohesion/Adhesion
• High surface tension
• High specific heat
• High heat of vaporization
• Lower density as a solid than a liquid
• Good solvent
Solute + Solvent = Solution
Hydrophilic and Hydrophobic
• Hydrophilic: water-loving, attracted to
water and dissolves easily in water
• Hydrophobic: water-fearing, does not
dissolve easily in water (nonpolar)
Acids, Bases and Buffers
Acid: high H+
pH: measure of
H+
Base: low H+
Acid Rain:
Destroys Lakes
Buildings and Statues
Ocean Acidification
• Overproduction of carbon dioxide through
fossil fuel combustion
• Oceans absorb carbon dioxide
• Ocean acidification: CO2 dissolves in
seawater and reacts with water to form
carbonic acid (lowers ocean pH)
• Less carbonate for reef calcification
CO2 dissolved in ocean reacts with
water to form carbonic acid
Carbonic acid dissociates into
bicarbonate and hydrogen ions
Hydrogen ions form more bicarbonate
with carbonate ions making them
unavailable for calcification by marine
animals such as coral
Coral reefs increase biodiversity,
protect shorelines, feeding ground for
fish species (fisheries), tourism
Figure 4.9
P. 63
Origin of life
(Miller)
ATP = Cellular Energy
Macromolecules
• Carbohydrates
• Lipids
• Proteins
• Nucleic Acids
How macromolecules are made and broken down
Monosaccharides- 1 sugar
Major nutrient for cells, stored as di or poly saccharide
Linear and Ring Forms
Disaccharides- 2 sugars
2 monosaccharides joined by condensation synthesis
Polysaccharides- 3 or more sugars
Many monosaccharides joined by condensation synthesis
Cellulose
Storage Polysaccharides
• Starch storage molecules in plants
-repeating units of glucose
• Glycogen storage of glucose in animals
• Cellulose also polymer of glucose in
plants, but different 3-D configuration
Makes up cell walls in plants
Difficult to digest
• Chitin makes up exoskeleton in insects
Lipids
Saturated: no double bonds
saturated with H
Solid at room temp.
Unsaturated: double bonds
cause bends
Liquid at room temp.
Phospholipids
Amphipathic: both hydrophilic and hydrophobic parts
Properties of water shape cell membranes
Amino Acids
How proteins are made: amino acids
are the building blocks
Primary Structure
Secondary Structure
Tertiary Structure-globular
Quaternary Structure
Nucleic Acids
DNA