Ecosystems: How they Work

1
Chapter 3

• Ecosystems How they Work

2
Chapter Overview

• The Nature of Matter (atoms and stuff)
• The Nature of Energy
• Energy in Life
• Energy flow in ecosystems
• Nutrient Cycles
• Human Dependancy

3
The Nature of Matter (1)

• Matter is made of Atoms
• Combined atoms are molecules
• Molecules with more than one type of atom compose
  compounds

4
Nature of Matter (2)Four Spheres

• Hydrosphere - all water on Earth
• Atmosphere - all gases above ground on earth
• Lithosphere - the Earths crust
• Biosphere - All life on Earth
• Matter is constantly exchanged between spheres,
  and especially between living and non-living
  spheres.

5
Key Elements - SPONCH

• Sulfur
• Phosphorous
• Oxygen
• Nitrogen
• Carbon
• Hydrogen

• Proteins
• ATP, DNA, RNA
• All Bio Molecules
• Proteins, DNA, RNA
• UhhhDUHHHH
• See Carbon

6
Macro Nutrients v. Micronutrients

• See table 3-1.
• Some nutrients found in large levels in all life
• Some found in small amounts in all living things
• Some required by a small number of living things
• Some toxic to some living things, but not others

7
Organic v. Inorganic

• Life depends on both organic and inorganic
  substances
• Organic include carbohydrates, lipids, nucleic
  acids, amino acids.
• Inorganic - anything without carbon. Na, Ca, S,
  etc some of these elements are sometimes part
  of organic molecules.

8
Energy Basics

• Forms of energy
• Light, heat, movement, electricity
• All are forms of movement (ability to move matter)

9
Kinetic v. Potential

• Kinetic - Movement
• Ex. Movement, heat, sound, light
• Potential - stored
• Raised substances, chemical bonds, springs
• One can be changed into the other.

10
Units of Energy

• Calorie (with a small c) - amount of energy to
  raise 1g of water by 1C
• Usually we use Calorie (with a big C) 1
  kilocalorie

11
Laws of Thermodynamics

• First law Energy is neither created nor
  destroyed - but can change forms.
• Second law When energy changes form there is a
  net loss in quality (a bunch is converted to
  heat)
• High forms chemical, springs, gravitational
• Low forms light, heat, sound