Bio 101 Principles of Biology I Test 1

1
Bio 101Principles of Biology ITest 1

• Chapters 1 2

2
Characteristics of life 1) composed of
organic carbon 2) organization a) atom -gt
molecule -gt pg 4-6 b) 2nd law of
thermodynamics vs entropy (equilibrium)
life contradicts 3) cell basic unit of
life lowest level of organization life
4) mechanism of energy input metabolism pg
6 5) homeostasis body temp blood
pressure osmolarity pg7 6) independent
reproduction development pg 7 7)
evolution pg 10
-gt next slide
3
Evolution...

• Change in the genetic make-up of a population
  over time resulting in a new species
• Population spatially isolated group VS
  Species reproductively isolated group
• ...involves random beneficial mutation
  ...driven by selective pressure a problem of a
  sort ...is preceded by natural
  selection
• Natural selection selection of the fittest
  individual leads to Evolution a
  new population which is a new species (???)
• Examples gazelle speed vs lion predation
  bacteria in mutagenic chemical

4
Biological classification scheme pg 8, 9
Binomial hierarchical system VS 3 domain
system

• 5 Kingdoms

• 7 levels of organization
• Kingdom
• Phylum
• Class
• Order
• Family
• Genus
• species

e u k a r y o t e s
plants animals
m i c r o b i a l
fungi protista
prokaryote
5
Kingdom characteristics

• Plants cellulose cell walls photosynthesis
• Animals wall-less aerobic respiration
• Fungi chitin cell walls filamentous
  saprophytes
• Molds very filamentous 1 saprophytes
• Yeast budding fermentation alcohols,
  acids, etc.
• Mushrooms
• Protista - Algae cellulose photosynthesis
  green diatoms - Protozoa
  wall-less aerobic respiration
• Prokaryotes peptidoglycan cell walls
• Bacteria binary fission metabolic diversity
  
• Cyanobacteria blue-green algae
  photosynthesis
• Archae genetically old extreme
  environments
• Vs Eukaryotes small simple binary fission
  DNA organization

6

• Science IS
• ...investigation of rational concepts testable by
  observation and controlled experimentation
• ...a systematic way to ask questions

• Science IS NOT
• ...about preconceived notions
• proof!!!

Pg 11-14
Scientific method 1.observation often an
accident 2.question specific
finite reasonable of hypotheses
3.hypothesis a proposed explanation
simple, specific, testable
???4.predictions??? in an if.then format
to cull hypotheses
5.controlled experimentation to DISPROVE
hypotheses controlls allow you to test 1
independent variable at a time if it
cannot be disproved becomes theory when
exhaustively tested, multiply verified by
detatched researchers 6.conclusion
NOT the answer NOT even the endit never ends
7

• Cell chemistry
• Element vs Compound pg 18
• Essential elements macro (lots) trace (PPB)
• Atom 3 subatomic particles.except H
• Periodic table pg 20
• atomic weight H neutrons
• atomic number H e- neutrons
  
• vertical groups horizontal periods
• arranged by increasing atomic number
• periodically recurring characteristics
  (groups) via electron configuration

12 C 6
8

• Isotope forms of element with different of
  neutrons pg21 unstable isotopes decay ?
  decay product C12 vs C14 decays half
  life 6000 yrs
• Electron orbitals pg 22
• Electrons arranged in orbitals or shells
  around nucleus
• Shells contain sub-shells which are filled
  inside ? out
• An S sub-shell will hold 2 electrons, a P
  sub-shell will hold 6
• The 1st shell is an S sub-shell will hold 2
  electrons total
• The 2nd shell is an S and P shell will hold 8
  electrons total

9
Continued

• Valence electrons pg 22
• a) are the outer shell electrons, therefore
• b) are the highest energy electrons
• c) are those most involved in chemical
  reactions
• d) determine chemical properties (for the most
  part)
• e) determine stability full stable
• Octet rule
• Atoms of C, N, O seek 8 electrons in their
  2nd shell
• 2S2 2P6 8 electrons in the 2nd shell
  10 electrons total
• But what if they dont? How can they get
  happy?

10
How do C, N O find their octet?
4

3

NH3 ammonia
2

11
Chemical bonds atoms sharing (?) e-s in
molecules pg 24

• Covalent bond atoms retain their shared
  electrons strongest bond type
  most important in Biology???
• a) polar C H Ex CH4 NH3
  H2O
• b) non-polar C C Ex O-O CC
  N?N
• Ionic bond molecules that ionize to form ions
  a) Na Cl ? NaCl ? Na Cl- b) 2H
  4O S ? H2SO4 ? HSO4- H
• c) Na O H ? NaOH ? Na OH-
• Hydrogen bond X(-).......H weakest NOT
  shared electrons
• yet VERY important in water determines
  properties

12
Characteristics of WATER pg 26

• 1) Cohesion / Adhesion H2O sticks to...
• blood xylem surface tension capillary
  attraction
• 2) High specific heat (heat capacity)
• amount of energy absorbed before ? temp
• heat absorbed in your body on Earth
  
• 3) High heat of vaporization evaporative
  cooling
• much energy required to break all H bonds
• 4) Ice less dense than liquid water
• ice insulates water column

water
ice
13
Characteristics of WATER pg 26

• 5) Polar solvent like dissolves like sugars,
  salts hydrophilic vs hydrophobic
• 6) Hydrophobic interactions oil vs water
• micelles membranes
• 7) Molecular spacing support
• molecular scafolding for proteins, fatty
  acids, etc.
• 8) pH acid/base H in H2O -log H
  scale buffer ?next
• Define Diffusion Osmosis

14
pH -log H

• Low H---------------------------------
  ----High H
• Bicarbonate buffer system critical to life on
  Earth
• H2O CO2 ? H2CO3 ?? H HCO3- ?? H CO3-2