Add four drops of diphenylalamine reagent to one drop of soil filtrate.
Results - Deep Blue: High nitrate content. Pale Blue: Low nitrate content.
Clover is abundant in those areas of low soil nitrate. Grass is abundant in areas of high nitrate level.
Adaptations of Organisms to their Environment
An adaptation is a feature that suits the organism to its environment. Adaptations are solutions to a problem.
Examples of Adaptations (see also competitive, predator and prey adaptations.)
Needle-like mouth parts of aphids tap food from the phloem of the plant.
Ladybird warning colouration: releases toxic fluids to deter predators.
Grass shoot tips are at or below ground: adaptation to survive grazing.
Field mice are nocturnal: predator avoidance.
Collection Methods in Ecological Studies (Mandatory Activity)
Textbook Diagrams of the following:
Small Mammal Trap
Pitfall Trap
Cryptozoic Trap
Pooter
Net: sweep net, insect net, plankton net or fish net.
Tullgren Funnel
Direct search for a particular species is a common practice.
Errors During Fieldwork
Bias: purposely choosing sample sites to get ‘good results’ or avoid work.
Too Few Sample Sites: may not give accurate representative results.
Surveyor Variation: students vary in ability, commitment and interest.
Equipment Quality: measurement and trapping success will be affected.
Changing Nature: results may depend on the time of day, season or year.
Chance: cannot survey every square centimetre so even with many sites some species may be missed.
Improper Trapping Techniques: all evasive species may not be captured and/or insufficient numbers captured in follow up surveying.
The Cell
Cell Theory
All living organisms are made up of cells and new cells are produced when live cells divide.
Textbook Diagrams: animal and plant cell as seen with light and electron microscopes.
Light Microscope Study Components of Animal Cells: cell membrane, cytoplasm, nucleus, chromosomes.
Extra Components of Plant Cells: cell wall, chloroplast, vacuole.
Electron Microscope Study Extra components and details:
Cell membrane, mitochondrion, nuclear pores, ribosomes, chromatin, details of chloroplast mitochondrion structure, double membrane nature of nuclear envelope and outline structure of cell membranes.
(The term protoplasm is useful and refers to the cell membrane, cytoplasm and its contents and the nucleus. The large vacuole of plant cells is not included.)
