Liceo classico “Gonzaga”
Milano
UTILIZZARE
SPAZIO PER
INSERIRE
FOTO/IMMAGIN
E DI
RIFERIMENTO
LEZIONE
Science course
From Prokaryotes to Eukaryotes
Teacher
Maria Elena Scortecci
Microscope
eye pieces
revolver
stage
focus knob
diafragm and condenser lens
light source
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Scientific classification
Prokaryotes
(bacteria and archaea)
• unicellular (cell size 1-10 µm)
• no nucleus (karyon) and
organelles
• special cell wall
• single circular cromosome +
plasmids
• aerobic or anaerobic
• reproduction by fission
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Scientific classification
Eukaryotes
(amoeboroa, fungi,
animalia, plantae)
• uni-multicellular (cell size 10100 µm)
• several pairs of chromosomes
in a nucleus
• many organelles
• only aerobic
• sexual reproduction
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How to observe cells
blotting paper
dye (i.e. methylene blue)
pipettes
water
coverslips
microscope slides
paddle
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Eukaryotes animalia
(human buccal mucosa)
• round cells
• small blue
nucleus
• cytoplasmic
membrane
• cytoplasm
• organelles
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Prokaryotes bacteria
(lactobacillus) from yoghurt
• very small cells: 2
µm long
• form filaments
• metabolize
lactose
• produce lactic
acid
• no organelles
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Eukaryotes fungi
(saccharomyces cerevisiae) from brewer yeast
• oval cells
• nucleuses
• dividing cells by
budding
• use glucose to
produce energy,
breathing
oxigen
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Eukaryotes plantae
(pelargonium)
• prismatic cells in mutual contact
• stiff
• typical organelles: chloroplasts,
chromoplasts, amyloplasts
• no dye, because they are naturally
stained cells
• photosynthetic cells:
CO2 + H2O  glucose + oxygen
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Eukaryotes plantae
cyclamen leaves, with stomata
and puzzle shape
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Eukaryotes plantae
onion cell
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Eukaryotes plantae
stomata cells in Setcrasea
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Eukaryotes plantae
tracheides in fennel
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Copyright 2012 © eni S.p.A.
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