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Introduction to Biodiversity

Define species, ecosystem and niche precisely; tell genetic, species and ecosystem diversity apart and weigh why biodiversity matters; analyse the threats to it and the effects of its loss, with Rwandan cases; and measure it in the field with random sampling, quadrats, transects, nets and capture–recapture, summarised with Simpson's index of diversity.

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Introduction to Classification

Place organisms in the taxonomic hierarchy and name them by the binomial system; use molecular evidence to judge relationships; compare the three domains and the five kingdoms; describe the structure, classification and importance of bacteria and of viruses; and use and construct dichotomous keys.

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Microscopy

Trace how microscopes, from Leeuwenhoek's single lens to the electron microscope, built the cell theory; name and use the parts of the compound light microscope and prepare and draw a specimen safely; calculate magnification, actual size and resolution and calibrate an eyepiece graticule; and compare light, transmission and scanning electron microscopes.

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Cell Structure and Specialisation

Identify what plant and animal cells show under the light microscope and measure them; describe the ultrastructure of eukaryotic cells revealed by the electron microscope and relate each organelle to its function; explain the fluid mosaic structure of the cell membrane; compare prokaryotic and eukaryotic cells; and relate the structure of specialised cells to their roles.

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Diversity of Specialised Tissues

Describe the meristematic and permanent tissues of plants, from parenchyma to xylem and phloem, and how they are arranged in roots, stems and leaves; describe the epithelial, connective, muscle and nervous tissues of animals; and explain the levels of organisation from cell to organism and the advantages and costs of being multicellular.

Lessons