Biodiversity and Classification

Life exists in a wide variety of forms which live in different niches. This section enables learners to be exposed to an array of life forms from microorganisms to macroscopic plants and animals. These are organised according to a man-made system of classification based on observable features. Learners explore the roles of organisms in an ecosystem including microorganisms that are a major cause of diseases. This strand also includes some evolutionary development in plant and animal phyla.

Classification: interactive animation

TOPIC

Biodiversity and Classification of Microorganisms (3 weeks, 12 hours)

CONTENT

Microorganisms: basic structure and general characteristics of the following groups (links with Grade 9 and 10):

– viruses

– bacteria

– protista

– fungi(Macroscopic organisms in the protista and fungi should only be mentioned – not studied in any detail)• Mention of the roles that these groups play in maintaining balance in the environment and web of life.• Symbiotic relationships, including, nitrogen fixing bacteria in plants and E.Coli in the human intestine (link with Grade 10).

• The effect and management of one disease from each of the four groups:

– viruses (rabies, HIV/AIDS, influenza)

– bacteria (blight, cholera, tuberculosis, anthrax)

– protists (malaria)

– fungi (rusts, thrush, ringworm, athlete’s foot).

Immunity, including plants and animals’ immune responses of against the infecting microorganism

Vaccinations (briefly).

• The use of drugs, e.g., antibiotics; effect on microorganisms

• The use of microorganisms to produce medicines (e.g., insulin and antibiotics).

• Traditional technology to produce, e.g., beer, wine and cheese.

INVESTIGATIONS

Where possible, the prevalence of bacteria/fungishould be demonstrated by growing cultures on agar plates, or bread mould (fungus) on bread.

• Look for evidence of bacterial/fungal diseases on plants (school and home). Map the distribution of one disease in the study area.