Perform microscopy and Gram stain preparation.
DefinitionPerformance should include
- preparation of a Gram stain using crystal violet, Gram's iodine, decolorizer, and safranin
- examination of a Gram-stained smear for gram-positive and gram-negative organisms.
- Why is immersion oil used when examining a smear for bacteria?
- What is the importance of using the correct order of reagents when performing a Gram stain?
- How do gram-positive organisms appear on a Gram stain?
- How do the gram-negative organisms appear on a Gram stain?
Related Standards of Learning
The student will demonstrate an understanding of scientific reasoning, logic, and the nature of science by planning and conducting investigations in which
- observations of living organisms are recorded in the lab and in the field;
- hypotheses are formulated based on direct observations and information from scientific literature;
- variables are defined and investigations are designed to test hypotheses;
- graphing and arithmetic calculations are used as tools in data analysis;
- conclusions are formed based on recorded quantitative and qualitative data;
- sources of error inherent in experimental design are identified and discussed;
- validity of data is determined;
- chemicals and equipment are used in a safe manner;
- appropriate technology including computers, graphing calculators, and probeware is used for gathering and analyzing data, communicating results, modeling concepts, and simulating experimental conditions;
- research utilizes scientific literature;
- differentiation is made among a scientific hypothesis, theory, and law;
- alternative scientific explanations and models are recognized and analyzed; and
- current applications of biological concepts are used.