Lab Safety and Scientific Method Quiz

Lab Safety

• Dispose of biological waste in biohazard bins, sharps in sharps containers, and chemical waste according to specific guidelines.
• Always wear appropriate PPE (gloves, goggles, lab coat) to protect against spills and exposure to harmful substances.
• MSDS provides information on material hazards, safe handling, first aid, and disposal.
• Discard items according to their classification (biohazard, chemical, general waste). Follow lab instructions and regulations.

Scientific Method

• Steps: Observation, Question, Hypothesis, Prediction, Experiment, Discussion, Conclusion (accept or refuse hypothesis).
• Variables: Independent (manipulated), Dependent (measured), Controlled (constant).
• Experimental group: Exposed to the independent variable.
• Control group: Not exposed to the independent variable; used for comparison.
• Placebo: A substance with no therapeutic effect, used as a control.

Karyotyping

• Process: Collect cells, induce cell division, arrest in metaphase, stain chromosomes, photograph and arrange.
• Chromosome identification uses size, banding patterns, centromere position, and shape.
• Down syndrome: Trisomy 21.
• Klinefelter syndrome: XXY genotype.
• Cri-du-chat syndrome: Deletion on chromosome 5.
• Turner syndrome: X0 genotype.
• Huntington's disease: Normal karyotype, HTT gene mutation.
• Chronic myeloid leukemia: Philadelphia chromosome (translocation between chromosomes 9 and 22).
• Chromosomal terms: Homologous chromosomes (pairs, one from each parent), autosomes (non-sex chromosomes), sister chromatids (identical halves of a duplicated chromosome), haploid (one set of chromosomes), diploid (two sets of chromosomes).

DNA & Genes

• DNA extraction steps: Cell lysis (breaking cell membranes), protein removal (using protease enzymes), precipitation (adding alcohol).
• Human genome: Approximately 3 billion base pairs, 20,000-25,000 genes.
• Aseptic technique prevents contamination by pathogens.
• Milk agar experiment tests bacterial casein breakdown; observes zones of clearance.
• Enzymes: Proteins that act as catalysts, speeding up biochemical reactions by lowering activation energy. Experimental plates contain the variable being tested, while control plates lack it for comparison.
• Genes: Segments of DNA that encode for proteins.

Test your knowledge of lab safety protocols, the scientific method stages, and karyotyping procedures. This quiz covers essential practices to ensure safety in the laboratory and the structured approach to scientific experimentation. Perfect for budding scientists looking to solidify their understanding of essential concepts.