Transcript Locomotion in Lower Organisms

What are the advantages
of locomotion?
1. Able to seek out food.
2.Able to seek shelter.
3.Able to escape from predators.
4.Able to seek mates.
Aim: How does locomotion occur in lower
organisms?
I. Locomotion in Lower Organisms
A. Locomotion in the Ameba
1. Uses pseudopods (false feet) to move
2. Cytoplasm inside cell pushes toward cell
membrane causing the ameba to move
B. Locomotion in the Paramecium
1. Uses beating cilia (microscopic hair-like
structures) to move
C. Locomotion in the Hydra
1. Is essentially sessile (does not move)
2. But… It does have the ability to move in 3 ways:
a. Somersault
b. Bend over, attach its tentacles to the sea
floor, and then inch its base closer
c. Glide along its base
D. Locomotion in the Earthworm
1. Uses two sets of muscles (circular and
longitudinal) to contract and lengthen its
body to inch it forward.
2. Uses setae (bristles) to anchor itself
into the ground
E. Locomotion in the Grasshopper
1. Has an exoskeleton (skeleton that is
outside organism’s body). Exoskeleton
is a non-living material.
2. It does not grow with organism, so
organism has to molt (shed) its
exoskeleton in order for a new, larger
one to grow.
3. Has six legs that are used for walking and
jumping.
a. Front two pair are for walking
b. Rear pair are for jumping – can jump
200x its body length!!!
4. 2 sets of wings.
a. outer pair are for protection
b. Inner pair are for flying
Q. What are the advantages of
locomotion?
Lyle, it is your turn today.
Of course Lyle!!! Locomotion is good for
finding food, seeking shelter, seeking
mates, and staying away from predators.
Nice job Lyle!
Q. Which organism uses setae to anchor
itself to the ground?
John Costanzo! Please answer this
question.
Yup, the earthworm. Nothing gets
past you John!
One more…
Q. How do the grasshopper’s front legs
differ from it’s back legs?
Allison, you are being awfully quiet.
Please answer this question for the
class.
Great job Allison!! The back legs are much
larger than the front two pair. This is
because the back ones are used for jumping.