Page 50 - Science Course 1 (Book 1)

Mo2-L2a: What are the Characteristics of Life?

Homeostasis

An organism’s ability to maintain steady internal Contractile vacuoles are cellular structures that help
conditions when outside conditions change is called maintain homeostasis by pumping excess water
homeostasis. from the cell

Hypo- Homeostasis Hyper-

Full Vacuole Empty Vacuole

Input information sent along Control Center Output:
afferent pathway to Information sent along
different pathway to
Receptor Effector
(Sensor)
Change defected
by receptor Response of effector
feeds back to influence
magnitude of stimulus
Stimulus: and return variable to
Produce homeostasis
change in
variable

Variable
(in homeostasis)

Imbalance

Maintaining homeostasis ensures that cells and the
organism can function normally and remain healthy.

Energy Desert paintbrush Sagebrush
Cells continuously use lizard
energy to transport
substances, make new
cells, and perform
chemical reactions.

Longnose
snake
Coyote

Golden-mantled Badger
squirrel
For most organisms, energy for life comes from the Sun.
The Sun’s energy can be passed from one organism to another.
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