1. BIO102: Biology and the Environment
Lecture 1: “Why is Earth the Living Planet”?

2. I. A Special Place
The Earth, from 6 billion kilometers, taken by the Voyager 1 space probe on Feb 14, 1990, as it left our solar system.

3. Formation of the Solar System
~ 4.6 bya

4. Planets

5. “Dwarf” planets (smaller than the Moon)

6. Body Diameter Distance
SUN 12 inches
Mercury 0.04 in 41 feet
Venus 0.10 in 77 feet
Earth 0.11 in 107 feet
Mars 0.06 in 163 feet
Asteriod belt……………………………………….
Jupiter 1.23 in 559 feet
Saturn 1.00 in feet
Uranus 0.40 in feet
Neptune 0.39 in feet
Pluto 0.02 in feet
Why no planet here?

7. B. The Early Earth
- meteorite bombardments
- Earth cools enough for water to condense and crust to form
- oldest rocks ~ 4.0 by (tectonic activity)

8. II. The Earth and its Neighbors
A. Size and Temps
-153 – 20oC
-88 – 58oC
462oC

10. Earth Venus Mars CO2 0.035% 96% 95% N2 77% 3.5% 2.7% H2O 1% 0.01%
II. The Earth and Its Neighbors
A. Size and Temps
B. Atmospheric Composition
Earth
Venus
Mars
CO2
0.035%
96%
95% N2
77%
3.5%
2.7%
H2O 1%
0.01%
0.007% Ar
0.93%
1.6% O2
21%
trace

11. II. The Earth and Its Neighbors
III. Why The Differences?
A. The Effects of Liquid Water

12. Lecture I: Water World
III. Why The Differences?
A. The Effects of Liquid Water
1. Water’s molecular structure
ATOMS:
- nucleus:
protons: charge = +1, mass = 1
neutrons: charge = 0, mass = 1
- shells/orbitals:
electrons: charge = -1, mass = ~0

13. YOU AND ME ALL KNOWN MATTER IS MADE OF THESE INGREDIENTS: GALAXIES
PLANETS
OCEANS
MOUNTAINS
AIR
PUPPIES
VIRUSES
YOUR FRIENDS
YOU AND ME

14. An element’s “ATOMIC NUMBER” = # Of PROTONS
III. Why The Differences?
A. The Effects of Liquid Water
1. Water’s molecular structure
An element’s “ATOMIC NUMBER” = # Of PROTONS
ATOMS:
- nucleus:
protons: charge = +1, mass = 1
neutrons: charge = 0, mass = 1
- shells/orbitals:
electrons: charge = -1, mass = ~0
ELEMENTS: differ in # of protons

15. III. Why The Differences?
A. The Effects of Liquid Water
1. Water’s molecular structure
ATOMS:
- nucleus:
protons: charge = +1, mass = 1
neutrons: charge = 0, mass = ~1
- shells/orbitals:
electrons: charge = -1, mass = ~0
ELEMENTS: differ in # of protons
ISOTOPES: differ in number of neutrons (and mass)

16. III. Why The Differences?
A. The Effects of Liquid Water
1. Water’s molecular structure
ATOMS:
- nucleus:
protons: charge = +1, mass = 1
neutrons: charge = 0, mass = 1
- shells/orbitals:
electrons: charge = -1, mass = ~0
ELEMENTS: differ in # of protons
ISOTOPES: differ in number of neutrons (and mass)
IONS: differ in number of electrons (and charge)
11 P
11 N
11 e-
11 P
11 N
10 e-
Charge = 0
Charge = +1

17. H2, O2, CO2, H2O, C6H12O6, proteins, DNA, etc…
III. Why The Differences?
A. The Effects of Liquid Water
1. Water’s molecular structure
BONDS:
Interactions between atoms, forming molecules:
H2, O2, CO2, H2O, C6H12O6, proteins, DNA, etc…
CEMENT
DNA

18. H2 Oxygen (Gas) = O2 O2, CO2, H2O, C6H12O6, proteins, DNA, etc…
III. Why The Differences?
A. The Effects of Liquid Water
1. Water’s molecular structure
Oxygen (Gas) = O2
BONDS:
Interactions between atoms, forming molecules:
O2, CO2, H2O, C6H12O6, proteins, DNA, etc…
- Covalent Bond: share electrons to fill outermost shell
2, 8, 8 (‘octet rule’)
shared equally = non-polar H2 2e
8 protons
8 protons 2e

19. WATER = H2O O2, CO2, H2O, C6H12O6, proteins, DNA, etc…
III. Why The Differences?
A. The Effects of Liquid Water
1. Water’s molecular structure
WATER = H2O
BONDS:
Interactions between atoms, forming molecules:
O2, CO2, H2O, C6H12O6, proteins, DNA, etc…
- Covalent Bond: share electrons to fill outermost shell
2, 8, 8 (‘octet rule’)
shared equally = non-polar
shared unequally = polar (partial charges)
The eight oxygen protons exert a stronger attractive force on the shared electrons than the single proton in each hydrogen atom – ‘pulling’ the cloud of electronegativity off the hydrogen protons, revealing ‘a part’ of their positive charge, and giving the oxygen atom a partial negative charge. Water is a ‘polar’ molecule… with charged ‘poles’.

20. O2, CO2, H2O, C6H12O6, proteins, DNA, etc…
BONDS:
Interactions between atoms, forming molecules:
O2, CO2, H2O, C6H12O6, proteins, DNA, etc…
- Covalent Bond: share electrons to fill outermost shell
- Ionic Bond: attraction between ions
A salt crystal:
IONIC BONDS between sodium and chloride ions

21. O2, CO2, H2O, C6H12O6, proteins, DNA, etc…
BONDS:
Interactions between atoms, forming molecules:
O2, CO2, H2O, C6H12O6, proteins, DNA, etc…
- Covalent Bond: share electrons to fill outermost shell
- Ionic Bond: attraction between ions
- Hydrogen Bonds: Weak attraction of partial charges

22. HYDROGEN BONDS IN THE THREE STATES OF WATER

23. III. Why The Differences?
A. The Effects of Liquid Water
1. Water’s molecular structure
2. Water is called the “universal solvent”
- ions and polar compounds dissolve in water

24. Lecture I: Water World
The Earth and Its Neighbors
Why The Differences?
A. The Effects of Liquid Water
1. Water’s molecular structure
2. Water is called the “universal solvent”
- ions and polar compounds dissolve in water
Charged regions of a glucose molecule

25. In presence of water, H+ replaces K+, Na+, and CA+2
Lecture I: Water World
III. Why The Differences?
A. The Effects of Liquid Water
1. Water’s molecular structure
2. Water is called the “universal solvent”
- ions and polar compounds dissolve in water
- Rocks are composed of ionic compounds (minerals)
- So, many rocks dissolve
K-Al-Si3O8
Na-Al-Si3O8
Ca-Al-Si2O8
In presence of water, H+ replaces K+, Na+, and CA+2
60% of Earth’s Crust:
Feldspar Minerals
Note: there is no carbon in these minerals

26. Lecture I: Water World
III. Why The Differences?
A. The Effects of Liquid Water
1. Water’s molecular structure
2. Water is called the “universal solvent”
3. Water dissociates into IONS
Hydronium:
Oxygen: 8 protons, 2e first shell, 8 second
3 H: 3 protons
Total: 11 protons, 10 electrons = +1 charge
(will readily give up H+ ion
Hydronium can give up an H+, so same net effect as above…

27. pH scale is negative exponent… so water = 7.0
Lecture I: Water World
III. Why The Differences?
A. The Effects of Liquid Water
1. Water’s molecular structure
2. Water is called the “universal solvent”
3. Water dissociates
In pure water, 1 in 10,000,000 (1 x 10-7) molecules will be dissociated at any one time
The “power” (in terms of exponent) of Hydrogen… you can think of it as percent or proportion of H+.
pH scale is negative exponent… so water = 7.0

28. HCl (Hydrochloric acid) dissociates much more readily in solution.
Lecture I: Water World
III. Why The Differences?
A. The Effects of Liquid Water
1. Water’s molecular structure
2. Water is called the “universal solvent”
3. Water dissociates
17+ 1+
HCl (Hydrochloric acid) dissociates much more readily in solution.
1 in 100 molecules are dissociated = 1 x 10-2
pH = 2.0

29. In presence of water, H+ replaces K+, Na+, and CA+2
Lecture I: Water World
III. Why The Differences?
A. The Effects of Liquid Water
1. Water’s molecular structure
2. Water is called the “universal solvent”
3. Water dissociates
4. Weathers rock, putting ions into solution
CATION DISPLACEMENT
K-Al-Si3O8
Na-Al-Si3O8
Ca-Al-Si2O8
In presence of water, H+ replaces K+, Na+, and CA+2
These ions go into solution…
60% of Earth’s Crust:
Feldspar Minerals

30. Lecture I: Water World
III. Why The Differences?
A. The Effects of Liquid Water
1. Water’s molecular structure
2. Water is called the “universal solvent”
3. Water dissociates
4. Carbon dioxide reacts with water to form carbonic acid

31. Abiogenic Limestone Formation
Bicarbonate ion
Carbonic acid
Carbonate ion
From ‘weathering’ of feldspars
Calcium Carbonate (limestone)

32. Earth Venus Mars CO2 0.035% 96% 95% Abiogenic Limestone Formation
Bicarbonate ion
Carbonic acid
Carbonate ion
Calcium Carbonate (limestone)

33. Limestone CaCO3 Lecture I: Water World III. Why The Differences?
A. The Effects of Liquid Water
B. Tectonic Activity and Subduction
Limestone
CaCO3

34. Lecture I: Water World
III. Why The Differences?
A. The Effects of Liquid Water
B. Tectonic Activity and Subduction
C. ???

35. Coccolithophore
(single celled marine algae)
Lecture I: Water World
III. Why The Differences?
A. The Effects of Liquid Water
B. Tectonic Activity and Subduction
C. The Effects of LIFE
1. Biogenic Limestone Formation
“Coquina”

36. Lecture I: Water World
III. Why The Differences?
A. The Effects of Liquid Water
B. Tectonic Activity and Subduction
C. The Effects of LIFE
1. Biogenic Limestone Formation
SHELLS
Settled out

37. 400 m
4 um (4/1000’s of a mm; 250,000 per meter)
100,000,000 deep, but they are crushed, so it’s actually more…

38. 400 m
4 um (4/1000’s of a mm; 250,000 per meter)
100,000,000 deep, but they are crushed, so it’s actually more…
Little things, big effects…

39. Where did all the Carbon Dioxide go? 1) Lithosphere
Limestone and Dolomite

40. Lecture I: Water World
III. Why The Differences?
A. The Effects of Liquid Water
B. Tectonic Activity and Subduction
C. The Effects of LIFE
1. Biogenic Limestone Formation
2. Photosynthesis
Photosynthetic bacteria

41. Light Dependent Reaction Light Independent Reaction
Overview:
Transfer radiant energy into chemical bond energy, stored in the bonds of molecules e-
C6 (glucose)
ATP
Photons bombard electrons, transferring energy to electrons
ADP+P
6 CO2 e-
Light Dependent Reaction
Light Independent Reaction
Where do the electrons come from?
Photosynthetic organisms split WATER:
2 (H-O-H) O + 4H+ + 4e-
So, CO2 from air is bound together into glucose (CO2 concentration declines)
Water is split, and oxygen gas (O2) is released to the air as a waste product O2

42. Earth Venus Mars CO2 0.035% 96% 95% N2 77% 3.5% 2.7% H2O 1% 0.01%
Lecture I: The Living Planet
III. Why The Differences?
A. The Effects of Liquid Water
B. Tectonic Activity and Subduction
C. The Effects of LIFE
1. Biogenic Limestone Formation
2. Photosynthesis
Earth
Venus
Mars
CO2
0.035%
96%
95% N2
77%
3.5%
2.7%
H2O 1%
0.01%
0.007% Ar
0.93%
1.6% O2
21%
trace
Little things (photosynthetic bacteria), big effects…

43. Where did all the CO2 go?
The atmosphere is no longer a major “reservoir” for carbon on our planet.

44. Where did all the CO2 go?
The atmosphere is no longer a major “reservoir” for carbon on our planet.
Most has been transferred to the lithosphere by limestone formation

45. Where did all the CO2 go?
The atmosphere is no longer a major “reservoir” for carbon on our planet.
Most has been transferred to the lithosphere by limestone formation
Or trapped as fossil fuels
(old life)

46. Where did all the CO2 go?
The atmosphere is no longer a major “reservoir” for carbon on our planet.
Most has been transferred to the lithosphere by limestone formation
Or trapped as fossil fuels
And there is nearly as much carbon
In living terrestrial biomass as in the atmosphere

47. Where did all the CO2 go?
The atmosphere is no longer a major “reservoir” for carbon on our planet.
Most has been transferred to the lithosphere by limestone formation
Or trapped as fossil fuels
And there is nearly as much carbon
In living terrestrial biomass as in the atmosphere
More in the entire biosphere, including decomposing material in soils and marine life

48. The Earth is a living planet…
It breathes.

49. And today?
The Earth is a living planet… it breathes.
CO2 – increased from 320 to 400 ppm 25% in 50 years
O2 – declined by 70 ppm, but it is
21% of the atmosphere (210,000,000 ppm)
So the decline of 70 ppm is not dramatic.

50. WHAT THE BIOSPHERE IS:
An extraordinary diversity of LIVING ORGANISMS

51. Millenium Ecosystem Assessment (2006)

52. Detritivores
Pollinators
Insect predators
Herbivores

53. Pollinators Insect Parasitoids Insect Predators

54. Herbivores Pollinators Parasites Detritivores
Malagasy Sunset Butterfly
Jewel Bug
Herbivores
Pollinators
Parasites
Detritivores
Long-legged fly

55. Herbivores Detritivores

56. (bacteria, algae, and plants)
PRODUCERS
(bacteria, algae, and plants)

57. Most vertebrate species are fishes
2,000,000 named species
= 2.5%

58. Herbivores, Predators, Detritivores, Pollinators
Herbivores, Predators, Detritivores, Pollinators

59. WHAT THIS DIVERSE BIOSPHERE DOES:

60. 1) Biodiversity increases “productivity” ... FOOD

61. Monoculture
They all need the same things at the same concentrations; they compete.

62. “Niche Complementarity”
Monoculture
Polyculture
They all need the same things at the same concentrations; they compete.
Combinations of different plants can be planted at higher density, and they use different "niches" and coexist. Even if abundance of "most productive" species drops, this loss can be offset.

63. “Positive Effects”
Monoculture
Polyculture
without beans
with beans
They all need the same things at the same concentrations; they compete.
Nitrogen fixing legumes (beans) nutrify the soil, increasing the growth of other plants. And you have beans!

65. 2) Biodiversity improves ecosystem services
Estimates of various Ecosystem Services - $U.S. trillions
Ecosystem services
Value (trillion $US)
Soil formation
17.1
Recreation
3.0
Nutrient cycling
2.3
Water regulation and supply
Climate regulation (temperature and precipitation)
1.8
Habitat
1.4
Flood and storm protection
1.1
Food and raw materials production
0.8
Genetic resources
Atmospheric gas balance
0.7
Pollination
0.4
All other services
1.6
Total value of ecosystem services
33.3
Source: Adapted from R. Costanza et al., “The Value of the World’s Ecosystem Services and Natural Capital,” Nature, Vol. 387 (1997), p. 256, Table 2.
TOTAL GLOBAL GNP (1997) = 18 trillion.
2) Biodiversity improves ecosystem services

66. 3) Aesthetics and Inspiration: Biodiversity enriches our cultures

67. But do we NEED all these species??
WHY PRESERVE BIODIVERSITY?
But do we NEED all these species??

68. There’s a lot of redundancy in nature…

69. Are all species equally important? If not, which ones are critical?

70. with
without

71. We don’t know which species are critical
So we need to save them all to maintain ecosystem function

72. HOW IS THIS DIVERSITY PRODUCED?
Evolution