1. 2.3 What Shapes an Ecosystem
Unit 2: Ecology
2.3 What Shapes an Ecosystem

2. Ecosystems All living and non-living things that interact as a system.
Includes:
Abiotic factors: non-living elements
Weather, sun, water, soil, temperature, etc.
Biotic Factors: living elements in an ecosystem
Plants, animals, and bacteria

3. For the following ecosystems:
Identify 3 abiotic factors.
Identify 3 biotic factors.
Identify an autotroph and a heterotroph.

7. Abiotic Factors: Water
Water is essential to life-Let’s Talk about some properties of water!

8. The Atom
The smallest particle of an element that retains the properties of the element
World Population:
Atoms in a penny:

9. Relative electrical charge
Particles that make up an atom
Particle
Symbol
Location
Relative electrical charge
Relative Mass
Actual mass (g)
Proton p+
In the nucleus 1+ 1
1.673 x 10-24
Neutron N0
Electron e-
In the space surrounding the nucleus -1
1/1840
9.11 x 10-28

10. Valence Electrons
Valence electrons are the furthest from the nucleus and are responsible for bonding between atoms.

11. The Structure of an Atom
Draw an atom in your notes. Be sure to label Protons, Electrons, Neutrons, and the Nucleus.

12. Element
Element: A substance that cannot be broken down into simpler substances
Ex- gold, copper, oxygen
92 occur naturally, 20+ are man-made

13. Compound
Compound: A substance that has 2 or more elements in a fixed ratio
Ex- Salt (NaCl)- made from a silvery metal and a greenish- yellow, poisonous gas
Neither are white or salty alone
Fixed composition… 1 Na, 1 Cl + =

14. Question? What Elements are necessary For Life?
Life requires about 25 chemical elements.