Chapter 3: Matter, Energy, and Life

1
Chapter 3 Matter, Energy, and Life

• Define matter, atoms, molecules
• Define energy and energy flow
• Define basic fundamentals of Ecology

2
I. From Atoms to Cells

• A. General Information
• 1. Ecology The study of the relationships
  between organisms and their environment
• Studies the life histories, distributions, and
  behaviors of individual species
• Studies the structure and function of naturals
  systems at the level of populations, communities,
  ecosystems, and landscapes

3
I. From Atoms to Cells

• A. General information
• 2. Holistic approach to ecology
• Uses systems to study interactions
• Observe the interconnected nature of systems and
  organisms within
• B. Atoms, Molecules, and Compounds
• 1. Matter everything that has mass and takes up
  space
• It exists in 3 distinct states
• Solid, liquid, and gas

4
I. From Atoms to Cells

• B. Atoms, Molecules, and Compounds
• Atoms have unique chemical forms called Elements
• Cannot be broken down into simpler forms by
  ordinary chemical reactions
• 4 elements make up 96 of the mass of all
  organisms
• The elements are O, C, H, N
• 2. Atoms - the smallest particles that exhibit
  the characteristics of the element
• Composed of electrons, protons, and neutrons

5
I. From Atoms to Cells

• Atomic number is the number of protons and is
  used to form the periodic table
• The number of neutrons may differ creating
  isotopes
• Atoms can join together to form molecules
• Molecules are any two atoms joined together
• Compounds are molecules created with different
  types of atoms
• Chemical bonds hold atoms together
• 2 major types of bonds are ionic and covalent

6
I. From Atoms to Cells

• 3. Ions
• Make up acids and bases
• Unequal numbers of electrons and protons
• Positive ions form acids (give up electrons
  readily, i.e. electron donors)
• Negative ions form bases (can bond easily with
  hydrogen ions, i.e. electron acceptors)
• The number of free hydrogen (hydronium) ions and
  hydroxide ions in solution is used to create the
  pH scale

7
I. From Atoms to Cells

• 4. Organic Compounds
• Some elements are used, by organisms, in
  abundance
• Some elements are used, by organisms, in trace
  amounts
• Any compound containing carbon is called an
  organic compound
• 4 major categories of organic compounds
• Carbohydrates
• Sugars, instant energy

8
I. From Atoms to Cells

• Lipids
• Fats and oils
• Also called hydrocarbons
• Long chains of carbon with 2 Hydrogen atoms
  attached
• Proteins
• Made up of amino acids
• Composed of amine group and carboxyl group

9
I. From Atoms to Cells

• Nucleic acids
• Made up of deoxyribose, phosphate group and a
  nitrogen base
• DNA
• 5. Cells
• Fundamental units of life
• Some are single-celled
• Bacteria, algae, protozoa
• Some are multi-celled
• Plants, animals, fungi

10
I. From Atoms to Cells

• 5. Cells (cont.)
• Chemical reactions occur because of enzymes
• Otherwise cells would burn up due to the
  combustion of metabolism
• Energy transfer is called metabolism in cells
• For example, sugar to ATP

11
II. Energy and Matter

• 1. General Information
• Essential constituents of all living organisms
• Energy provides the force to hold structures,
  tear apart structures, and move materials
• 2. Energy Types and Quantities
• Energy is defined as the ability to do work
• Kinetic Energy is the energy of movement

12
II. Energy and Matter

• Potential Energy is stored energy, the energy
  of position
• Chemical Energy is the energy stored in the
  food you eat, energy of chemical bonds
• Measured as Joules (physics), BTUs (propane),
  and Calories (food)
• Power is the rate of doing work
• Heat describes the total energy not used in the
  movement of an object lost energy

13
II. Energy and Matter

• Temperature is the speed of motion of an atom
• 3. Conservation of Matter
• Matter, like energy, is neither created nor
  destroyed
• Called the Conservation of Matter
• Matter is transformed and combined

14
II. Energy and Matter

• 4. Thermodynamics and Energy Transfers
• Organisms use gases, water and nutrients
• Metabolism waste products are returned to the
  environment in a different form (by-products)
• Energy is not recycled (in the biosphere)
• Must provide energy from an external source

15
II. Energy and Matter

• Energy has a one-way path that eventually ends up
  in a low-temperature sink
• First Law of Thermodynamics
• Energy is conserved
• Cannot be created nor destroyed, only transferred
  from one form to another form
• Second law of Thermodynamics
• As energy is transferred or transformed, there is
  less energy to do work
• Energy is lost to the environment

16
II. Energy and Matter

• Recognizes a tendency of all natural systems to
  go from a state of order toward a state of
  increasing disorder
• Entropy Entropy Rules!
• Also called the Chaos Theory
• For example Life to Death

17
III. Energy for Life

• 1. Solar Energy Warmth and Light
• Organisms survive at different temperature ranges
• Low temps affect metabolism negatively, not
  enough energy produced to survive
• High temps break down molecules rendering them
  non-functional
• Photosynthesis converts sunlight into organic
  compounds that can be used as energy

18
III. Energy for Life

• 1. Solar Energy Warmth and Light
• Cellular respiration converts the organic
  compounds of photosynthesis into ATP

19
IV. From Species to Ecosystems

• 1. Populations, Communities and Ecosystems
• Species are all of the organisms that are
  genetically similar enough to reproduce viable
  offspring
• Populations consist of all of the members of a
  species living in a given area at a given time
• Extinctions can be large scale (complete) and
  small scale (local)

20
IV. From Species to Ecosystems

• 1. Populations, Communities and Ecosystems
• A community is all of the populations of
  organisms living and interacting in a particular
  area
• An ecosystem is the biological community and its
  physical environment
• Boundaries between communities and ecosystems may
  be difficult, but must occur
• Ecosystems are separated based on communities,
  climate, and productivity of the communities

21
IV. From Species to Ecosystems

• 2. Food Chains, Webs, and Trophic Levels
• Primary Productivity is the amount of biomass
  produced in a given area
• Higher productivity ecosystems TRF, TSF, and
  Wetlands
• Lower productivity ecosystems Deserts, Tundra
• Net Primary Productivity includes decomposition
  and can change the scale of productivity
• TRF is no longer a high productivity ecosystem

22
IV. From Species to Ecosystems

• 2. Food Chains, Webs, and Trophic Levels
• Consumption of plants is considered Secondary
  productivity
• Food Chains are a linking of feeding series
  between organisms
• For example, Grass ? Grasshopper ? Frog
• Or Grass ? Cow ? Man (steak, yeah baby!)
• In communities, consumers have primary food
  sources
• Will eat that food source first
• Some consumers have secondary food sources
• Dont compete as well for this food source

23
Food Chain
24
Food Web
25
IV. From Species to Ecosystems

• 2. Food Chains, Webs, and Trophic Levels
• Some consumers are opportunistic
• Stumble on food (not the norm)
• Will eat primary food source, but will anything
  it happens across
• Typically are called omnivore
• Examples are bears, raccoons
• A Trophic Level is an organisms feeding status
• Producers are the first trophic level (autotroph)

26
IV. From Species to Ecosystems

• Primary consumers are the second trophic level
  (herbivore)
• Secondary consumers are the third trophic level
  (carnivore)
• There is energy loss at each trophic level
• Typically the consumer receives 1/10th of the
  energy 9/10th is lost
• Most food chains are 3 trophic levels, some are
  4, very few are 5
• Due to the energy loss during each consumption

27
(No Transcript)
28
IV. From Species to Ecosystems

• Tertiary consumers are either top carnivores or
  scavengers (third, fourth, or fifth trophic
  level)
• Detritovores consume leaf litter, debris, and
  dung (third, fourth, or fifth trophic level)
• Decomposers finish the break-down process of
  materials (third, fourth, or fifth trophic level)
• Turns the material into very elemental forms

29
(No Transcript)
30
IV. From Species to Ecosystems

• 3. Ecological Pyramids
• Number of organisms (by percent) in each trophic
  level
• Can be used to describe the available energy for
  habitats, communities, or ecosystems

31
(No Transcript)
32
V. Material Cycles and Life Processes

• 1. The Carbon Cycle
• Has 2 purposes for organisms
• Structural component of organic molecules
• Energy storage in the chemical bonds
• Starts with CO2 intake by producers
• Carbon is incorporated into sugar
• Sugar is burned in all organisms through Cellular
  Respiration, releasing CO2 into the ecosystem

33
V. Material Cycles and Life Processes

• 1. The Carbon Cycle (cont.)
• Some carbon is lost to carbon sinks
• Ex. Coal, Oil, and Trees
• Carbon is not released until combustion
• Calcium Carbonate (CaCO3) is incorporated into
  shells of organisms
• Very difficult to break down, especially in
  anoxic conditions at the bottom of lakes and
  oceans

34
(No Transcript)
35
V. Material Cycles and Life Processes

• 2. The Nitrogen Cycle
• Organisms can not exist without organic compounds
  comprised of Nitrogen
• Ex. Proteins, nucleic acids, amino acids, etc.
• Inorganic forms of Nitrogen are utilized by
  plants to form organic compounds
• Nitrogen is the most abundant element in the
  atmosphere, but it is unusable as N2

36
V. Material Cycles and Life Processes

• 2. The Nitrogen Cycle (cont.)
• The nitrogen cycle provides usable N for plants
• Nitrogen-fixing bacteria turn the N2 into usable
  N for plants (NH3 ammonia)
• Nitrite forming bacteria change NH3 into NO2
  (nitrite)
• Nitrate forming bacteria converts NO2 into NO3
  (nitrate)
• NO3 is used by the plants

37
V. Material Cycles and Life Processes

• 2. The Nitrogen Cycle (cont.)
• Plants convert NO3 into NH4 (ammonium)
• NH4 is used to create amino acids
• Nitrogen re-enters the system when organisms die
  through decomposition
• Nitrogen, also, re-enters the system through
  metabolic waste (uric acid)
• Urination dumps nitrogen (called pulses) into
  streams, rivers, and soil
• Bacteria consume and turn the waste into NH3

38
(No Transcript)
39
Root Nodules containing N-fixing bacteria
40
N-fixing bacteria
41
V. Material Cycles and Life Processes

• 3. The Phosphorus Cycle
• Phosphorus is used by organisms for energy
  transfer processes
• Major component of fertilizers
• Begins with phosphorus leaching from rocks into
  groundwater
• Inorganic phosphorus is absorbed by producers
• Turned into organic compounds

42
V. Material Cycles and Life Processes

• 3. The Phosphorus Cycle
• Reintroduced to the environment through
  decomposition of organic material

43
(No Transcript)
44
V. Material Cycles and Life Processes

• 4. The Sulfur (Sulphur) Cycle
• Used in proteins
• Determine acidity of rainfall, surface water, and
  soil
• Most is in the form of rocks and minerals
• Iron disulfide (FeS2), calcium sulfate (CaSO4)
• Inorganic sulfur is released into the atmosphere
  as SO2 and SO4 (Sulfate)

45
V. Material Cycles and Life Processes

• 4. The Sulfur (Sulphur) Cycle (cont.)
• Sulfur has many oxidative states
• Ex. Hydrogen Sulfide (H2S), Sulfur Dioxide (SO2),
  Sulfate ion (SO4-), and S (elemental)
• Human activities release sulfur
• Ex. Burning of fossil fuels
• Phytoplankton release large quantities of sulfur
  to the atmosphere (especially during warming
  trends)
• DMS ? SO2 ? SO4 (DMS is Dimethylsulfide)
• Increases the earths albedo

46
(No Transcript)
47
(No Transcript)