BACTERIA
· they are unicellular organisms
· bacteria that occur in clusters but function on its own-colonial bacteria
· some are autotrophic9they manufacture food using light energy by the process of photosynthesis and chemosynthesis-using energy released from chemical processes),some heterotrophic-unable to manufacture their own food
· they are found everywhere, in air,soil and water
· they prefer moisture and darkness
· grow and reproduce best btwn temps of 30-37para
· they can survive at temps from 18-70
· some are parasites-they obtain their food from organisms around them
· bacteria that cause disease-pathogens
· mutualsim-both organisms in the relationship benefit
· parasitism-one benefits and the other is harmed
· commensalism-where one benefits by using the other for only support
structure
· cell wall
· cells have a slime capsule which prevents the cell from drying out
· they have whip-like flagella by which they move about in liquid
· cytoplasm covered by plasmalemma
· no nucleus,chromatin network is found in nucleoid
· they are prokaryotic -no true nucleus
biological importances
· page 138-141
PROTISTS
· UNICELLULAR,some such as seaweed,multicellular
· most are aquatic
· euglena and green algae-autotrophic
· entamoeba histolytica-heterotrophic(parasitic)
· slime moulds engulf food by phagocytosis
· PHAGOCYTOSIS- the process by which large particles are engulfed
· produce asexually-binary fission
THE AMOEBA
·
· unicellular
· advantage: the single cell can exist independantly, carrying out all life processes
· disadvantage: since one cell carries out all life processes, there are no specialised structures present for each process
· asymmetrical, it has a constantly changing shape because of the on-going development of the finger like outgrowths called pseudopodia, which is used in food capture and locomotion.
· surroounded by plasmalemma(cell mem.)-controls the passage of substances in and out of the cell
·...