2.  Where does energy in living systems come from?  How is it transferred from one organism to another?

3.  ENERGY  Where does all of the energy on planet earth come from? o Sunlight (ultimate energy source) o Chemical (stored in inorganic chemical compounds)

4.  Plants  “Produce” their own food using energy from sun light  Autotrophs o Auto = Self o Troph = Food Examples: o plants, bacteria, algae

5.  Photosynthesis captures light energy and uses it to power chemical reactions that convert carbon dioxide and water into oxygen and energy-rich carbohydrates (sugar).  Adds oxygen to the atmosphere and removes carbon dioxide.

6.  Heterotrophs  Get their energy by eating other organisms Omnivore: Eats both Carnivore (secondary consumer): Eats meat Herbivore (primary consumer): Eats plants

7.  Scavengers feed on dead organisms  Ex: earthworms, ants, and vultures.

8.  Detrivores break down organic matter  Recyclers: turn waste into materials for producers  Ex: bacteria and fungi

9.  Energy always flows from producers to consumers

10.  Linear-start with producer and end with top predator  a relationship of organisms that depend on each other for energy or food/energy  EX: Algae is food for fish which are food for squid which are food for sharks.  Note: The arrows point the way energy flows, NOT what it eats!

11.  Food chains connected together  Arrows pointing in the direction of energy flow.  If one organism is removed, other organisms may be endangered or possibly die out.

12.  Life creates a pyramid when converting energy  Each level is called a trophic level

13.  Green plants (some bacteria & algae) that are able to make their own food  Lowest trophic level

14.  1 ° consumers are herbivores (plant eaters)  Ex: some insects, deer, or mice.

15.  2 ° consumers are carnivores (flesh eaters)  They feed on herbivores  Ex: Amphibians

16.  3 ° consumers are carnivores  Ex: snakes and hawks

17.  Concentrations of harmful substances increase as you move to higher trophic levels.

18.  With every step in a Trophic Level:  Organisms loose 90% of their energy to heat  Only 10% of energy is passed on  Ex: an organism on one trophic level needs to eat 10x more than an organism one trophic level below Useable energy decreases from 1 trophic level to the next!

20.  A pyramid of biomass shows the amount of living organic matter at each trophic level.  The greatest biomass is at the bottom of the pyramid.

21.  A pyramid of numbers shows the number of individual organisms at each trophic level.

22.  In most ecosystems, the pyramid of numbers and the pyramid of biomass are similar, with the numbers of individuals on each level decreasing from the level below it.

23.  In some cases, however, consumers are much smaller than organisms they feed upon.  Thousands of insects may graze on a single tree, for example. The tree has a lot of biomass, but represents only one organism.  In such cases, the pyramid of numbers may be turned upside down, but the pyramid of biomass usually still has the normal orientation.