INRODUCTION Flashcards
DEFINE PROTOZOOLOGY
Study of protozoa (unicellular organisms) in which all physiological functions are carried out by the organelles of the cell
KINGDOM PROTISTA
-Diverse collection of eukaryotic organisms
-which lack tissue differentiation
-Single celled
-Move independently
-Many are free living, others are parasites
complex life cycles that take place in the cells, bloodstream and tissues of the host (invertebrate-ticks, mosquitoes or vertebrates-mammals, avian)
Parasitic protozoa
Most are zoonotic – low host specificity
KINGDOM PROTISTA
Differences between Prophyta and Protozoa
cell wall- rigid/thick
nuclear material- well defined with membrane
nutrition– holozoic saprozoic
reproduction- binary fission along longitudinal axis except ciliates
Protozoa
cell wall - non rigid/ thin
nuclear material - dispersed
nutrition- holophytic
reproduction - binary fission along transverse axis
Types of Nucleus
Vesicular
Compact
chromatin concentrated in a single mass (endosome or nucleolus)
Vesicular
chromatin evenly distributed (homogenous), present in ciliates
Compact
reproductive function
Micronucleus
Organelles in the cytoplasm
(powerhouse of the cell)
Mitochondria
vegetative function
Macronucleus
carries organs of locomotion (prolongations of the ectoplasm)
Cytoplasm
outer part (homogenous and hyaline appearance)
Ectoplasm
(regulates osmotic pressure & eliminates waste material)
contractile vacuole
(protein synthesis)
Ribosomes
(enzymes for digestion)
Lysosome
(collect dehydrated proteins)
Golgi bodies
Functions ectoplasm:
Movement
Food ingestion
Excretion
Respiration
Protection
Granular, pigmented
Contains food vacuoles (role in nutrition)
Endoplasm
Movement of Protozoa
To obtain food
For reacting to physical and chemical stimuli
protozoa Very marked movement
flagellates and ciliates
Modes of Movement
Cilia
Pseudopodia
Flagella
Gliding
ciliates, Balantidium, Trichomonas (fine, short, flagella like structures
Cilia
false feet (Entamoeba)
Pseudopodia-
Mastigophora species (whiplike filamentous structure from a basal granule in the ectoplasm) ex. Trypanosomes
Flagella
Toxoplasma, Sarcocystis, Eimeria (no locomotory organelle
Gliding-
Types of Nutrition
Holophytic
Holozoic
Saprozoic
Autotrophic
No veterinary importance, COH synthesized by chlorophyll (characteristics of plants)
Holophytic
pseudopodia or a cytostome are used to ingest food material from plants or animals and passed to a food vacuole (Pre-formed food utilized thru special organs)
Holozoic
uses micropyle (micropore) to ingest fluids/solids
Eimeria
– ingest tissues of host through a temporary opening in the body wall (pinocytosis)
Entamoeba, Balantidium
absorb nutrients by diffusion and directly used by the organism; stored food seen inside glycogen granules (absorption of dissolved organic matter)
Saprozoic
live entirely from inorganic compounds (proteins, COH & lipids are synthesized from them)
Autotropic-
parasitic protozoa nutrition
= either holozoic or saprozoic; none are autotrophic or holophytic
Ways of Excretion
Osmotic pressure
Diffusion
Precipitation
Involves the contractile vacuoles, ectoplasm, cytopyge and other structures.
(Most common)
takes free molecular oxygen in and expels carbon dioxide
Aerobic respiration
Sexual -involves the male and female gametes
a) Conjugation
b) Syngamy
survive under low oxygen tension since free oxygen is seldom available in the intestine of host
facultative or obligate anaerobes