Prokaryotes and eukaryotes; evolution of cells
Answers are for parents and teachers.
1
Compare a prokaryotic and a eukaryotic cell in a table by 4 features.
Nucleus: absent / present; DNA: circular / linear chromosomes; membrane organelles: absent / present; division: fission / mitosis.
2
Write one distinguishing feature each for animal, plant and fungal cells.
Animal: no cellulose wall; plant: plastids; fungus: chitin-like wall.
3
Describe the symbiosis hypothesis in 3–4 sentences.
A large host cell took in aerobic and photosynthetic prokaryotes and lived in symbiosis with them; these became mitochondria and chloroplasts.
4
Why can viruses be called neither prokaryotes nor eukaryotes?
They are not cells; they consist of a nucleic acid and a protein coat.
5
A blue-green film forms on an aquarium wall and turns out to be a blue-green alga. Is it a prokaryote? Explain.
Yes, cyanobacteria are prokaryotes: no nucleus and no membrane organelles, but they photosynthesise with chlorophyll.