Transcript Document 7198791

Chemistry of Life
But first…
http://www.bitd.clrc.ac.uk/Activities/ST1/FunParts.gif
Reproductive excess
 More individuals are born than can possibly
live, and therefore there is a struggle to
survive.
http://lion-den.tripod.com/images/lioness-and-cub-facts/lion-02.jpg
http://lionguardians.wildlifedirect.org/files/2008/03/esk_deadlioness2_tn.jpg
http://www.lionresearch.org/behavior_guide/infant.html
Variation
 There is variation among organisms within a
reproducing population.
http://bluepyramid.org/ia/lion.jpg
http://itswild.org/files/images/Lion.jpg
http://www.jpbutler.com/franklin-park-zoo/lion-side.jpg
http://farm1.static.flickr.com/18/92631504_a676c080e7.jpg?v=0
http://www.lion-picture.com/Images/Lion_King_africa_safari_Lion.jpg
http://www.bbc.co.uk/nature/wildfacts/factfiles/picpops/images/lion22.jpg
http://blogs.cyberciti.biz/hm/wp-content/uploads/2006/10/lion-picture-photo.jpg
http://animals.nationalgeographic.com/staticfiles/NGS/Shared/StaticFiles/animals/images/primary/african-lion-closeup.jpg
Variation is heritable.
 This variation is heritable, and passed directly
from parent to offspring.
http://www.spottycat.com/marlos/emporium/lion/lion42.jpg
http://travel.msn.co.nz/img/article/lion_cub.jpg
http://www.sydney.com.au/images/zoo-lions.jpg
http://www.aza.org/AZAPublications/PhotoContest/Images/LionWithCub.gif
http://thumbs.dreamstime.com/thumb_149/11794510043PYPf7.jpg
http://img.dailymail.co.uk/i/pix/2007/07_02/lionkingDM1807_600x400.jpg
Survive and Reproduce
 The life forms best suited to their environments
have the best chance to survive and reproduce.
http://africahowtocall.com/images/lion4.jpg
http://gallery.photo.net/photo/4750684-lg.jpg
http://www.krugerpark.co.za/images/img049-lion-pride.jpg
http://66.166.92.72/web/geo2/Masai%20Mara/Game%20Drive/Lion%20Pride.jpg
In other words
 The lion gene pool houses all lion traits.
 The parents are part of the gene pool, and their traits are passed
on to their offspring.
 There are more cubs born than survive to adulthood.
 The offspring with the most fit inheritance will have the best
chance to survive and reproduce.
http://farm1.static.flickr.com/13/17436178_dd46ec5172.jpg?v=0
http://www.africa-nature-photography.com/images/DCWP_603_034w-Lion-Cubs-Picture.jpg
Chemistry of Life
And now…
http://www.bitd.clrc.ac.uk/Activities/ST1/FunParts.gif
Atoms
 An atom is the smallest
component of an
element that can:
 maintain the element’s
basic chemical properties
 Has any chemical
properties
 An element is a
substance that is made
entirely from one type of
atom
http://www.funksoulkitty.org/periodictable.jpg
Atomic Model
 Atoms make up
everything
 Particles make an atom
 Nucleus
 Protons
 Neutrons
 Electron cloud
surrounding nucleus
Pictured above is an atom with
2 electron shells
http://web.buddyproject.org/web017/web017/images/atom.JPG
Nucleus
 Protons ( + )
 Have an electrical charge
of +1
 Comprised of 2 up and 1
down quarks which are
held together by gluons
 Neutrons ( o )
 Have no electrical charge
 Comprised of 1 up and 2
down quarks which are
held together by gluons
http://www.pentek.com/applications/15_1/heart2quarks_small.jpg
Nucleus
 Protons and Neutrons
weigh about the same
 The majority of the mass
(over 99%) is the
nucleus
 A proton’s positive
charge repels other
protons
 Held tightly together by
presence of neutrons
and the interaction of the
quarks in each, and
nuclear forces
http://commons.wikimedia.org/wiki/File:Helium_atom_QM.png
Nucleus
 The atomic mass of
an atom is the total
number of protons
plus the average
number of naturally
occurring neutrons
 Since the electrons
have such little
mass, they are not
included
http://lc.brooklyn.cuny.edu/smarttutor/core3_21/images/nature/7.a.Isotopes.gif
Electrons
 Electrons (e-)
 Have an electrical charge
of -1
 Fundamental particles
(meaning that they cannot
be broken into smaller
parts)
 The mass of an electron is
1/2000 of the mass of a
proton
Related particles in bubble chamber
http://www.broward.edu/faculty/ghauer/10714_home.jpg
Size
 Atoms are measured in
nanometers, picometers or
ångströms (a non-SI unit of
measure)
 1 m = 1,000,000,000 nm
 1 m = 1,000,000,000,000 pm
 1 m = 10,000,000,000 Å
 Visible light 400nm (violet) to
700nm (red)
 Hydrogen, e.g., has an
empirical radius of 0.025 nm
(or 25 picometers)
http://www.acr.atr.co.jp/~wendin/Pictures/corral.gif
Size
 If we could enlarge an atom to take up the same
amount of space as our Earth and Moon
 The diameter of 1 proton would be the length of 1 football field
http://mceer.buffalo.edu/connected_teaching/photos/Football.jpg
Size
 If we could enlarge an atom to take up the same
amount of space as our Earth and Moon
 The diameter of the nucleus would be the length of 3 football
fields
http://mceer.buffalo.edu/connected_teaching/photos/Football.jpg
Size
 If we could enlarge an atom to take up the same
amount of space as our Earth and Moon
 The distance between the nucleus and the electron would be
the distance the Moon is to the Earth
http://upload.wikimedia.org/wikipedia/commons/6/60/Speed_of_light_from_Earth_to_Moon.gif
Size
 If we could enlarge an
atom to take up the
same amount of space
as our Earth and Moon
 The size of the electron
would be the same as a
golf ball
http://www.aerospaceweb.org/question/aerodynamics/sports/golf-ball.jpg
Or…
 If the nucleus of an
atom were the size of
a golf ball
 The electron would
still be too small to
see
 It would be found
about ¼ mile away
¼ mile
http://www.us43drags.com/AERIAL.JPG
Or…
 7 million atoms
joined together in a
straight line would be
about 1mm long
1mm
http://www.k12math.com/math-concepts/measurement/ruler-cm.jpg
Atoms
 The number of protons
determines the element.
 The number of neutrons
can range from 0 in
hydrogen to more than
146 in uranium
 The electrons are
usually the same
number as protons
http://lpmpjogja.diknas.go.id/kc/a/atom/atom-h-he-li-na.gif
Atoms
 The smallest atom is
hydrogen
 1 proton
 1 electron
 The largest natural
occurring atom is
plutonium (only in trace
quantities)
 96 protons
 96 electrons
 ±148 neutrons
http://www.webelements.com/
http://geology.isu.edu/geosciences/periodic_table.gif
Symbols
 Elements are
abbreviate, e.g.
16
 O for oxygen
 Hg for mercury




Atomic Mass
Atomic Number
Charge
Number of element’s
atoms in molecule
8
O
2-
Understood that there is
only 1 atom of oxygen
202
80
2+
Hg
2
Isotopes
 A form of a chemical
element with the
same atomic number
as another element
but having a different
atomic mass.
http://www.medterms.com/script/main/art.asp?articlekey=4059
http://lc.brooklyn.cuny.edu/smarttutor/core3_21/images/nature/7.a.Isotopes.gif
Isotopes
 Hydrogen is the simplest
atom
 1 proton
 1 electron
 Deuterium (isotope of
hydrogen)
 1 proton
 1 electron
 1 neutron
 Tritium (isotope of hydrogen)
 1 proton
 1 electron
 2 neutrons
http://images.encarta.msn.com/xrefmedia/aencmed/targets/illus/ilt/T046738A.gif
Isotopes
 Carbon 12 has
 6 protons
 6 electrons
 6 neutrons
 Carbon 13 has
 6 protons
 6 electrons
 7 neutrons
 Carbon 14 has
 6 protons
 6 electrons
 8 neutrons
http://images.encarta.msn.com/xrefmedia/aencmed/targets/illus/ilt/T050525A.gif
Electrons
 Electrons (e-) are found in a
cloud around the atom in
shells
 Theoretical limits to each
shell
 1st shell – 2 electrons
 2nd shell – 8 electrons
 3rd shell – 18 electrons
 4th shell – 32 electrons
 5th shell – 32 electrons
 6th shell – 18 electrons
 7th shell – 8 electrons
http://miss.ramos.science.googlepages.com/orbit.jpg/orbit-full;init:.jpg
Theoretical
 When filling orbital
shells for noble
gases, the 3rd shell
gets very tricky





Can hold 18
Fills 8
Moves to the 4th shell
Partially fills 4th shell
Chemists do not
agree to the reason
Valence Shells
 The valence shell is
the outmost electron
shell in an atom
 The number of
electrons in the
valence shell
determine how
reactive the atom is
 Atoms want full
valence – Octet rule
1 Hydrogen
1st shell reactive
1st shell not reactive
Valence shell
2nd shell reactive
8 Oxygen
Valence Shells
 Atoms join together
to form molecules
Water molecule
Slightly positive
Slightly negative
Energy in Atoms
 Electrons, in the ground
state, are in the lowest
shells permitted (for
hydrogen, in the first
shell)
 If energy (in this case,
light energy) is added to
their system, the
electrons move to an
outer shell
 Can only move into a
more energetic shell if
there is a vacancy
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/excitation.gif
Energy in Atoms
 Energy can be converted
to a different kind of
energy, but it cannot be
created or destroyed
 Low energy – electrons
found closest to nucleus
 Add energy – electrons
move away from nucleus
http://www.brooklyn.cuny.edu/bc/ahp/LAD/C7/graphics/C7_EnergyElectrons_1.GIF
Niels Bohr
 Since the energy emitted
was of characteristic
amounts and never in
amounts in between,
that the stable shells
were of specific
distances from the
nucleus and that
electrons could only
exist stably at those
fixed distances from the
nucleus
http://upload.wikimedia.org/wikipedia/commons/d/d5/Niels_Bohr_Albert_Einstein_by_Ehrenfest.jpg
Demonstration
http://www.cyberphysics.pwp.blueyonder.co.uk/topics/radioact/Radio/EMSpectrumcolor.jpg
Hydrogen’s Orbital Shells
http://www.kennethsnelson.net/atom/Portrait4.html
Spectral Analysis
 Hydrogen







Violet (380-435nm)
Blue(435-500 nm)
Cyan (500-520 nm)
Green (520-565 nm)
Yellow (565- 590 nm)
Orange (590-625 nm)
Red (625-740 nm)
http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/modpic/hydtube.jpg
Spectral Analysis
 Helium









Violet 438.793
Indigo 443.755
Blue 447.148
Blue 471.314
Cyan 492.193
Yellow 501.567
Yellow 504.774
Orange 587.562
Red 667.815
http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/modpic/heltube.jpg
Spectral Analysis

Neon















Green 540.1nm
Yellow 585.2nm
Yellow 588.2nm
Orange 603.0nm
Orange 607.4585.2nm
Orange 616.4585.2nm
Red-orange 621.7nm
Red-orange 626.6nm
Red 633.4nm
Red 638.3nm
Red 640.2nm
Red 650.6nm
Red 659.9nm
Red 692.9nm
Red 703.2nm
http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/modpic/neoncomp.jpg
Spectral Lines
 Increase energy, and the
electrons move further
away from the nucleus –
kinetic energy
 As atom loses energy,
the electrons move
closer to nucleus
 The energy is converted
to light (another form of
energy
 The wavelength of light
given off depends on the
energy level of the
http://isites.harvard.edu/fs/docs/icb.topic225467.files/images/TowerofSpectra02.jpg
electron
Emission Lines
http://utahscience.oremjr.alpine.k12.ut.us/Sciber06/9th/Stand_1/images/Hydrogen.jpg
http://faculty.njcu.edu/tpamer/chemprep/Goldberg4.htm
Chemical Bonding
 Ionic Bonding
 Held together by
strong electrical
charges in the
individual atoms
 Easily disassociate
when in solution
http://geology.isu.edu/geosciences/periodic_table.gif
Chemical Bonding
 Hydrogen has 1
electron in the
valence shell, but
“wants” 2
 Oxygen has 6
electrons in the
valence shell, but
wants 8
 Share electrons
 Bonding
Ions
 The +1 electrical charge
of a proton and the –1
electrical charge of an
electron cancel each
other, so that the atom
has a net 0 charge
 If an atom gain an
electron, the atom will
have a net – charge
 If an atom loses an
electron, the atom will
have a net + charge
http://www.worsleyschool.net/science/files/pH/page.html
Compounds, Molecules
and Mixtures
 Molecules of an element are two or more atoms of the same
element bonded together – atmospheric oxygen
 Molecules of a compound are two or more atoms bonded together
– water or methane gas
 Mixtures are elements or molecules that are not chemically
bonded together – milk
http://wps.prenhall.com/wps/media/objects/165/169061/GIFS/AAAUASN0.JPG
Other bonds
 Hydrogen bonds
 Hydrogen atoms are
attracted to each
other, but weakly
 If there are enough of
them…
 Van der Waal
 Dipole
 Cation pi
http://harvestwater.org/images/f/f9/3D_model_hydrogen_bonds_in_water.jpg
Free Energy
 Diffusion
 Osmosis
http://campus.queens.edu/faculty/jannr/cells/cell%20pics/osmosisMicrographs.jpg
http://www.sunripe.sunripeproduce.com/images/tangerine%20peeled%20nice.jpg
http://www.personal.psu.edu/users/t/r/trp2/diffusion60min.jpeg
Biochemistry
 Water
 Universal solvent
 Cohesive – hydrogen
oxygen attraction
 Adhesive – sticky with
other materials
 Expands when it
freezes
 Low melting point
 High freezing point
 Naturally found in all
three states
http://apod.nasa.gov/apod/image/0501/earth_apollo17.jpg
Proteins
 20 Amino Acids
 Different properties
 Polar
 hydrophilic
 Non-polar
 hydrophobic
 negative
 positive
http://www.phschool.com/science/biology_place/biocoach/images/biomembrane1/Fluidmem.gif
http://www.detectingdesign.com/images/Abiogenesis/Amino%20Acid%20Chart.jpg
Proteins
 Organized molecules




Primary structure
Secondary structure
Tertiary structure
Quaternary structure
http://wofford-ecs.org/DataAndVisualization/GenomicData/images/protein.gif
Proteins
 This is the basis for
all components of the
cell
 Eye color or skin
color – a protein
called melanin
 Hormones are
proteins
 And the list goes on
and on and on
http://campusapps.fullerton.edu/news/arts/2003/photos/protein-art.jpg
http://www.agen.ufl.edu/~chyn/age2062/lect/lect_06/4_18.GIF
http://porpax.bio.miami.edu/~cmallery/150/chemistry/hemoglobin.jpg
Cell Molecules
Lipid
Protein
DNA
RNA
http://upload.wikimedia.org/wikipedia/commons/5/5b/DNA_As_Structure_Formula_(German).PNG
http://academic.brooklyn.cuny.edu/biology/bio4fv/page/molecular%20biology/rna-structure.jpg
Animal Cell
http://www.cartage.org.lb/en/themes/Sciences/Zoology/AnimalPhysiology/Anatomy/Anatomy/animalcell.jpg
Plant Cell
http://www.molecularexpressions.com/cells/plants/images/plantcell450.jpg
Bacteria Cell
http://www.phs.princeton.k12.oh.us/Departments/Science/bheckman/prokaryote.bmp
Other organelles
http://www.usoe.k12.ut.us/curr/science/sciber00/7th/cells/acrobat/orgtable.pdf
Nucleus
http://www.cartage.org.lb/en/themes/Sciences/Zoology/AnimalPhysiology/Anatomy/Anatomy/animalcell.jpg
http://www.geocities.com/auroranex/nucleus.gif
Chromatin
 Highly organized DNA
http://upload.wikimedia.org/wikipedia/commons/7/79/Chromatin_chromosome.png
Ribosomes
 RNA builds proteins
http://publications.nigms.nih.gov/insidethecell/images/ch2_ribosome_proteinbig.jpg
Mitochondria
http://www.nsf.gov/news/overviews/biology/assets/interact08.jpg
http://www.steve.gb.com/images/science/chloroplast_electron_transport_chain.png
Endoplasmic Reticulum
http://micro.magnet.fsu.edu/cells/endoplasmicreticulum/images/endoplasmicreticulumfigure1.jpg
Golgi Apparatus
http://employees.csbsju.edu/hjakubowski/classes/ch331/cho/ergolgi.jpeg
Lysosomes
http://micro.magnet.fsu.edu/cells/lysosomes/images/lysosomesfigure1.jpg
Cellular Membranes
 Phospholipid bilayer
 Fluid Mosaic Model
 Imbedded with
proteins
 Only on cytoplasmic
side
 Only on interstitial fluid
side
 Transmembrane
proteins
http://www.ncnr.nist.gov/programs/reflect/rp/biology/cell_membrane_p2.jpg
Transport
http://2.bp.blogspot.com/_v2GFIISzHOU/R7lPf2YflUI/AAAAAAAAACk/-7hq4edM1TM/s400/Facilitated%2BTransport.jpg
Metabolism
 Metabolism is all
biochemical
processes of an
organism
www.freerepublic.com
Enzymes (a protein)
http://lhs2.lps.org/staff/sputnam/Biology/U4Metabolism/enzyme.gif
Questions?
B Shaw, Paramylodon from American Museum of Natural History 2004