Trypanosoma lewisi: Protozoa Classification, Locomotion, Nutrition, Reproduction - Prof. M, Study notes of Zoology

Download Trypanosoma lewisi: Protozoa Classification, Locomotion, Nutrition, Reproduction - Prof. M and more Study notes Zoology in PDF only on Docsity!

“Protozoa”

• Not multicellular• Classified into many phyla or

clades

BUT:

• Now being organized into more

groups by using molecularbiology

Protozoan Classification

(Hickman)

• Phyla

• Retortamonada– Axostylata– Chlorophyta– Euglenozoa– Apicomplexa– Ciliophora– Dinoflagelatta

Cytoplasmic Movements

microfilaments in cell Fig. 11.

All is based on contractile fibers• mitotic spindle and centrioles• eukaryote flagellum and cilia• ameboid movement and cytoplasmic

streaming

Locomotion

9 + 2 double fibrils

Fig. 11.2, 11.

Flagellum

Cilia

•^

For example,

Paramecium, a protist, is

hypertonic when compared to the pond waterin which it lives.– In spite of a cell membrane that is less

permeable to water than other cells, waterstill continually enters the

Paramecium cell.

• To solve this problem,

Paramecium have aspecialized organelle,the contractile vacuole,that functions as a bilgepump to force water outof the cell.

Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

Fig. 8.

Tree of life web page

• Http://tolweb.org/tree/phylogeny.html

•^

In

pinocytosis

, “cellular drinking”, a cell

creates a vesicle around a droplet ofextracellular fluid.– This is a non-specific process. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

Reproduction

-^

Asexual– Fission; binary fission produces two identical

cells

• Multiple fission; many individuals formed

through cytokinesis

• Budding- progeny is smaller, then grows -^

Sexual– Isogametes/ansiogametes– Most “protozoa” are haploid

-^

Encystment

• Fig 11.
• Fig 11-
• Fig 11.