Download Ecological Pyramids

Ecological
Pyramids
How much energy is passed
from one organism to the
next?
Ecological Pyramids
What is an ecological pyramid?
It’s a diagram that shows the amount
of energy/matter in each trophic level
Trophic levels:
1. Producer (autotroph)
2. Consumer (heterotroph: herbivore/omnivore)
1.
2.
3.
1st level (heterotroph: omnivore/carnivore)
2nd level (heterotroph: omnivore/carnivore)
3rd level (heterotroph: carnivore)
Types of Ecological Pyramids
Open your book to page 72
1. Energy pyramid
2. Biomass pyramid
3. Pyramid of numbers
Why is the pyramid
smaller at the top?
Observations
 Only 0.1% of the energy makes it to the
top level
 1500 grams of grain can only be made
into 50 grams of human tissue
 Only one hawk is at the top, while there
are numerous producers at the bottom
Reason
 ENERGY IS LOST AS HEAT AT EACH LEVEL
What you need to know
 How
much energy passes from one
trophic level to the next (1st ecological
pyramid)
 The relative number of organisms at each
trophic level
Classwork
 You
will work on a worksheet in class.
 Read ALL the instructions. Most likely you
will find the answer to your question, so
you do not need to ask the instructor.
 You will each turn in a worksheet.
 Work in groups of 2, or 3. (NOT four)
 You may talk quietly as long as your
conversation is about the assignment.
Discuss classwork
Homework
 Read
section 3-1 and 3-2.
 Do the following problems:



Page 65 #1, 4.
Page 73 #1-5.
Page 83 #14, 18.