Liceo classico “Gonzaga”Milano

Science course

From Prokaryotes to Eukaryotes

Teacher

Maria Elena Scortecci

UTILIZZARE SPAZIO PER INSERIRE FOTO/IMMAGINE DI RIFERIMENTO LEZIONE

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Microscope

diafragm and condenser lens

stage

revolver

eye pieces

focus knob

light source

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 10-100 µm)

• several pairs of chromosomes in a nucleus

• many organelles

• only aerobic• sexual reproduction

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How to observe cells

microscope slides

pipettes

waterdye (i.e. methylene blue)

paddle

coverslips

blotting paper

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Eukaryotes animalia(human buccal mucosa)

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• round cells• small blue

nucleus• cytoplasmic

membrane• cytoplasm • organelles

Prokaryotes bacteria(lactobacillus) from yoghurt

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• 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

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• oval cells• nucleuses• dividing cells by

budding• use glucose to

produce energy, breathing oxigen

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Eukaryotes plantae(pelargonium)

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• 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

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cyclamen leaves, with stomata and puzzle shape

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Eukaryotes plantae

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onion cell

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Eukaryotes plantae

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stomata cells in Setcrasea

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Eukaryotes plantae

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tracheides in fennel

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