This document discusses locomotion in protozoa. It describes four types of locomotor organelles found in protozoa: pseudopodia, flagella, cilia, and pellicular contractile structures. It then discusses the four main methods of locomotion used by protozoa: pseudopodial movement, flagellar movement, ciliary movement, and metabolic movement. Flagellar movement involves three types of strokes: paddle stroke, undulating motion and simple conical gyration. Ciliary movement involves the rapid backward strokes of many cilia that push the protozoan forward. Metabolic movement is seen in certain flagellates and sporozoans and involves gliding, wriggling or peristaltic

1. LOCOMOTION
• Locomotion is directional
movement that enables
someone or something to
move from one location to
another.
• The word derives from the
Latin words loco (place)
and motio (to move).

2. • Pseudopodia
• Flagella
• Cilia
• Pellicular Contractile Structure
Locomotor
organelles
in
Protozoa
include:

3. A. Pseudopodia
• Pseudopodia or false
feet are temporary
structures formed by
the streaming flow of
cytoplasm.
• Pseudopodia are of
the following types:
• Lobopodia
• Filopodia
• Reticulopodia
• Axopodia

4. 1. Lobopodia
• These are lobe-like pseudopodia with
broad and rounded ends, as in
amoeba.
• Composed of both ectoplasm as well
as endoplasm.
• Lobopodian move by pressure flow
mechanism.

5. 2. Filopodia
• These are more or less filamentous
pseudopodia
• Usually tapering form base to pointed
tip, as in Euglypha.
• Filopodia are composed of ectoplasm
only.

6. 3. Reticulopodia
• The reticulopodia are filamentous.
• Filament are branched and
interconnected.
• Reticulopodia display two-way flow of
cytoplasm.

7. 4. Axopodia
• They have needle like straight
pseudopodia.
• They contain a central axial rod which is
covered by granular and adhesive
cytoplasm.
• Axopodia display two-way flow of
cytoplasm.
• Axopodia are characteristic of heliozoans.

8. B. Flagella
• Flagella are the locomotor organelle
of flagellate protozoa, like euglena,
Trypanosoma, etc.
• A typical flagellum consist of an
axoneme.
• Axoneme arises from a basal
granule, the blepharoplast or
kinestosome.
• Fibers of axoneme remain
embedded in a fluid matrix.

9. • In axoneme, 9+2
arrangement is
present.
• Each peripheral pairs
bears a double row of
short arms, made of
protein called dynein.
• Peripheral paired fiber
is connected to inner
ring through radial
spoke.

10. Types of Flagella
• Stichonematic: Only one row of lateral
appendages.
• Pantonematic: Two or more rows of
lateral appendages.
• Acronematic: Lateral appendages are
absent and axoneme ends as a terminal
naked axial filament.
• Pantacronematic: Two or more rows of
lateral appendages and the axoneme
ends in terminal naked axial filament.
• Anematic: Simple without any lateral
appendages and a terminal naked
filament.

11. C. Cilia
• Cilia, characteristic of ciliata, they
also exhibit 9+2 structure.
• These are highly vibratile small
ectoplasmic processes.
• They are nine paired peripheral
fibers are enclosed within a
delicate sheath.

12. Basal granules show nine
peripheral subfibre triplets, each
disposed in a twist-like fashion.
Each cilium arises from a
thickened structure
blepharoplast.
One sub-fibre or microfibre of
each peripheral pair bears a
double row of short, projection,
called arms.
Basal Body/Centriole Forming

13. D. Pellicular Contractile
Structures
• In many Protozoa are found
contractile structures, in pellicle or
ectoplasm, called myonemes.
• These may be in the form of ridges and
grooves (e.g., Euglena), or contractile
myofibrils (e.g., larger ciliates), or
microtubules (e.g., Trypanosoma).

14. Method of Locomotion
i. Basically there are four known methods by which Protozoa
move:
ii. Pseudopodial movement,
iii. Flagellar Movement,
iv. Ciliary movement,
v. Metabolic movement.

15. i. Pseudopodial
Movement
• The pseudopodium is fixed
on the support by some
adhesive secretion and the
protoplasm of the body
gradually flows into it.
• The ectoplasm is dissolved
and the endoplasm flows.
• New Pseudopodia appear
and, by the repetition of the
process, the animal slowly
creeps forward

16. ii. Flagellar movement
• Three types of flagella movement have been recognized:
• Paddle Stroke: Common movement of a flagellum is
sideways lash, consisting of an effective down stroke and a
relaxed recovery stroke.
• Undulating Motion: Wave-like undulations in flagellum,
proceed from tip to base and from base to tip.
• Simple conical gyration: Bustchli’s screw theory postulates a
spiral turning of flagellum like screw. This exerts
propelling action , pulling the animal forward through
water.

17. iii. Ciliary Movement
• Some Protozoan’s move with the help of
cilia.
• Cilia are small hair-like structures, present
usually in large numbers on the body
surface.
• A cilium has a practically the same histology
as that of flagellum.
• The cilia act as small oars and the backward
strokes are swift, which push the animal
forward.

18. iv. Metabolic Movement
• This is a typical of certain flagellates (e.g. Euglena) and most sporozoans at certain stages
of their life cycles.
• Such organism are seen to show gliding or wriggling or peristaltic movement.
• Contractile myonemes or microtubules, present in their pellicular walls.
• Movement of this kind are also referred as gregarine movements.