Fungi
- some cause decay to our food
- some cause diseases to humans and animals e.g. ringworms
- may be used as food e.g. mushrooms, yeast
- some are used in production of antibiotics e.g. penicillin, chloromycin, streptomycin
- yeast is used in brewing industry, baking and source of vitamin B
- many cause diseases to our crops e.g. late blight
- important in recycling nutrients in soil since they cause decay of organic matter
- mycorrhizal association in forest development may help in water intake/absorption
- help in nitrogen fixation
BACTERIA
- are useful in the manufacture of antibiotics
- silage formation,
- fermentation of cheese, butter, milk yoghurt
- curing of tea, tobacco and retting flax
- formation of vitamin B12 and K
- enzymes such as amylase and invertase
- hormones such as insulin
- vinegar, acetic acid, lactic acid, citric acid
- in septic tanks and modern sewage works make use of bacteria
- biogas production
- saprophytic bacteria are used in compost decomposition or cause decay
- symbiotic bacteria are used in compost decomposition or cause decay
- symbiotic bacteria in herbivores/ruminants help in digestion
- some diseases in animals/humans and plants are caused by bacteria
- many bacteria cause food spoilage/decay
- nitrifying and nitrogen fixing bacteria increase soil fertility/make nitrates available
- denitrifying bacteria reduce soil fertility/convert nitrates into nitrogen/reduce nitrates