Ecology 6,4

• Biologie
• Middelbare school
• havo
• Leerjaar 2

Today's lesson

Discuss the pyramid of numbers and biomass

Start on a summary

6,4 Ecological pyramids

Simplify!

A food web is too complicated to study in detail

Break it down into producers, consumers, and so forth

See a food chain graphically to better understand relationships between organisms.

Pyramid of numbers:

• The amount of individual organisms in the community reflected in a pyramid.
• Each trophic level of a food chain is represented with a bar. 
• The amount of individuals in each trophic level is represented by the size of the bar. 

Pyramid of biomass:

• The total biomass of all organisms in the community reflected in a pyramid.
• The total biomass of each trophic level of a food chain is represented with a bar. 
• The amount organisms in each trophic level is multiplied by the mass of each individual to get the biomass.

This is a pyramid of ...

1. numbers
2. biomass
3. it is not a pyramid
4. it can be both a pyramid of numbers and of biomass

What does the pyramid of biomass show?

1. The biomass of one animal
2. The biomass in a link in the food chain
3. The number of organisms in a link in the food chain

a pyramid of numbers has always the shape of a pyramid

1. correct
2. incorrect

What did we learn?

1. The water cycle

2. The carbon cycle

3. Pyramid of numbers

4. Pyramid of biomass

To Do:

Read 6,4 and Do Qs 15 and 16

Read 6,9 and Do Qs 30 and 31