Welcome!
Please get your interactive notebook and
pick up your owl pellet folder from the
lab table.
Please read the board!
Owl pellets

What were the most common bones?

What do owls eat? What are their prey?

How many animals were in your pellet?
Sooooo . . .

A barn owl produces on average two pellets a day.

Prey eaten per day ___________

Prey eaten per week ____________

Prey eaten per month ____________
How much space would this
food chain require?

If each rodents needs 5 m2 to find enough food for
itself, how much space would all the rodents in the one
pellet need to survive?

How much space would all the rodents for one MONTH
need to survive?

Do owls need more or less space than a rodent? WHY???
Which trophic levels need the
most space? The least? Why?
**Energy pyramid –
A graph showing how much total
energy is in related trophic
levels.
carnivore
herbivore
Primary producer
Prairie Ecosystem
Hawks
Snakes
Mice
Grasses
How do living organisms transform
or use energy?

Movement

Metabolism… transforming
chemicals like food into energy
like ATP

Heat… a by-product of
metabolism

Growth and Development

Reproduction
Energy is converted
between trophic levels.

Energy is always converted as it moves from one trophic
level to the next. Most of the energy is converted into a
form that can’t be used again.

How would one organism use up it’s energy?

Energy is converted into motion, heat, growth, and metabolism.
**Law of Conservation of
Energy:

**Energy is neither created nor
destroyed; it is transformed from
one type to another

Example: sunplantappleATP
(fuel of cells)you writing these
notes
How do living organisms transform
or use energy?

Movement

Metabolism… transforming
chemicals like food into energy
like ATP

Heat… a by-product of
metabolism

Growth and Development

Reproduction
**The Rule of 10%
Of all energy taken in by a trophic level,
most of it is used in growth, motion,
metabolism or body heat. Only 10% of
the energy is available to the next trophic
level.
Energy pyramids have as many
levels as links in a food chain!
Reflection on left side:

An owl needs much more habitat than a mouse because
...

When a carnivore eats an herbivore most of the energy .
..