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A variety of resources have been selected to help your understanding of National Biology, Cell Biology.  Select from the menu opposite or navigate to an alternative part of the Hyndland Biology Department website using the options above.

Coverage for the Unit is detailed below (updated 6/5/14):

1 Cell structure

Cell ultrastructure and functions to include: cell wall, mitochondrion, chloroplast, cell membrane, cytoplasm, vacuole, nucleus, ribosome and plasmid using examples from typical plant, animal, fungi and bacterial cells.

Functions of structures exemplified later in this Unit.
Fungal structure in terms of similarity to plant and animal cells but with a different cell wall structure.
Bacterial structures only to include absence of organelles and a different cell wall structure to plant and fungal cells. Chemical composition of cell walls not required.

2 Transport across cell membranes

a. The cell membrane consists of lipids and proteins and is selectively permeable.

b. Passive transport is along a concentration gradient and does not require energy.

c. Diffusion in cells as the movement of molecules down a concentration gradient.

d. Osmosis as the movement of water molecules across a membrane in terms of water concentration.

e. Animal cells can burst or shrink and plant cells can become turgid or plasmolysed in different solutions.

f. Active transport requires energy for membrane proteins to move molecules and ions against the concentration gradient.

Different concentrations of substances exist between cells and their environment.

Diffusion in terms of concentration gradients and importance to cells could include glucose, carbon dioxide, oxygen or amino acids.

Appropriate examples for active transport could include sodium and potassium in nerve cells, or iodine in seaweeds.

These processes can be applied across relevant areas of the Course.

3 Producing new cells

a. Maintenance of diploid chromosome complement by mitosis.

b. Sequence of events of mitosis, including the terms chromatids, equator and spindle fibres.

c. Cell production by cell culture requires aseptic techniques, an appropriate medium and the control of other factors.

d. Mitosis is required for growth and repair.