Protazoans Amoeba Flashcards
Amoeba
naked or enclosed in a shell (naked includes Amoeba and pelomyxa). live in freshwater and sea water and in soil. They are bottom dwellers that feed on algae, bacteria, protozoa, and other microscopic organisms. The ameba is gray, transparent, irregularly shaped.
Plasmalemma
outer cell membrane
ectoplasm
is inside the plasmalemma, a peripheral rim and stiff. also referred as hayline cortex.
endoplasm
looks clear even glassy because it lacks a subcellular organelles.
Locomotion
the way an ameba moves.
pseudopodia
“false feet” changes shape by thrusting out the pseudopodia. moves Amoeba.
hayline cap
advancing end of the pseudopodium.
food vacuoles
particles of food surrounded by water and enclosed in a membrane.
phagocytes
cells and unicellular organisms that engulf foreign particles. a ingestion known as phagocytosis.
lysomes
contents are digested by hydrolytic enzymes secreted into the food vacuoles in tiny membrane bound organelles.
contractile vacuole
a clear bubble containing no particles. rids the ameba of the excess water that has been taken in along with food vacuoles and acquired by osmosis.
Nucleus
a disc-shaped often refractive to light. perfectly spherical.
Binary fission
amebas reproduce asexually by a type of mitotic cell division.
Parasitic Amebas
entamoeba are found in humans and other vertebrates. Gingivalis lives in the mouth and feeds on bacteria around the base of the teeth.
histolytic lives in large intestine and causes dysentery. the mature cyst usually contains 4 small nuclei.
Shelled Amebas
Arcella which live in bogs or swamps where much vegetation exists
difflugia found in leaf-choked puddles and aquatic vegetation
