Lab Exam I Study Guide PDF

**Lab Exam I** Study Color Guide Yellow -- PowerPoint Topic \| Red -- Important \| Green -- Answer \| Blue -- Example \| **Bold** -- **Urgent** **Exercise 1: Lab Safety** **Disposing Of Items**: - Dispose of biological waste, like used Petri Dishes & Culture Materials in designated biohaza...

**Lab Exam I** Study Color Guide Yellow -- PowerPoint Topic \| Red -- Important \| Green -- Answer \| Blue -- Example \| **Bold** -- **Urgent** **Exercise 1: Lab Safety** **Disposing Of Items**: - Dispose of biological waste, like used Petri Dishes & Culture Materials in designated biohazard bins. - Sharp items (Needles, Glass) should go into sharps containers. - Chemical waste **needs** to be discarded according to **specific guidelines** provided for each substance. **Protecting Yourself**: - **Always** wear Gloves, Goggles, **and** Lab Coats to protect against spills **and** exposure to harmful substances. Familiarize yourself with safety protocols for handling specific chemicals. **MSDS** (Material Safety Data Sheet): - **It provides information about hazards of materials and how to handle them safely**, **including** **first aid measures** and **disposal instructions**. **Discarding Items**: - Items used in experiments **should** **be** **discarded** according to **their classification** (Biohazard, Chemical, **or** General Waste) Always follow lab instructions and local regulations. **PPE (**Personal Protective Equipment): - This includes Gloves, Goggles, Lab Coats, **and** Face Shields **designed** to protect you from exposure to hazards. **Scientific Method** **Steps of the Scientific Method**: - Observation - Question -- **Why**? - Hypothesis -- **Maybe**... - Prediction -- **If**, \*Hypothesis\*, Then, - Experiment****Discussion - Conclusion -- **Accept or Refuse the Hypothesis**. HEAP OQC **Variables**: - **Independent Variable**: The variable you manipulate (Amount of Light) - **Dependent Variable**: The variable you measure (Plant Growth) - **Controlled Variables**: Factors kept constant (Soil Type, Water Amount) - **Experimental Group**: The group **exposed** to the **Independent Variable**. - **Control Group**: The group **not exposed** to the **Independent Variable** for comparison. - **Placebo**: A **substance** with **no therapeutic effect** **used as a control** in testing. **Exercise 2: Karyotypes** **Making a Karyotype**: - Collect Cells (From Blood **or** Amniotic Fluid) - Induce Cell Division (Using Mitogens) - Arrest Cells in Metaphase (Using Colchicine) - Stain Chromosomes (To see Bands) - Photograph and arrange them by size and shape. **Characteristics for Karyotyping**: - **Size**, **Banding Patterns**, **Centromere Position**, and **overall Shape** helps in **identifying** and **comparing** **chromosomes**. **Karyotypes of Specific Conditions**: - **Down Syndrome**: Trisomy 21 (Three copies of **chromosome 21**) - **Klinefelter Syndrome**: XXY genotype. - **Cri-du-Chat**: **Deletion** on **chromosome 5** - **Turner Syndrome**: X0 (Missing **one** X chromosome). - **Huntington's Disease**: **Typically**, **normal karyotype**; mutation **occurs** in the gene (**HTT**) - **Chronic Myeloid Leukemia**: Philadelphia chromosome (Translocation between **chromosomes 9 and 22**). **Chromosomal Terms**: - **Homologous Chromosomes**: **Chromosome Pairs**, **one** from each parent, that are **similar in shape and size**. - **Autosomes**: **Non**-sex chromosomes (22 Pairs in humans) - **Sister Chromatids**: Identical halves of a **duplicated** **chromosome**. - **Haploid**: Cells with **one set** of chromosomes (Gametes) - **Diploid**: Cells with **two sets** of chromosomes (Somatic Cells) **Exercise 3: DNA, the Code of Life** **DNA Extraction Steps**: 1. **Cell Lysis**: **Breaking** down **Cell Membranes** using **detergents**. 2. **Removal of Proteins**: **Using** **Protease Enzymes** to **digest** proteins. 3. **Precipitation**: **Adding** **Alcohol** (Ethanol) to **separate** **DNA** **from** the solution. **Human Genome Size**: - Approximately 3 billion base pairs, **containing** about 20,000 -- 25,000 genes **Exercise 4: What is a Gene?** - **Aseptic Technique**: Procedures to **prevent** **contamination** by **Pathogens**, **including** sterilizing equipment **and** using gloves - **Milk Agar Experiment**: An experiment to test **the enzymatic breakdown of casein** (Milk Protein) **by** **bacteria**, using **milk agar plates** to observe zones of clearance around bacterial colonies. - **Enzymes**: **Proteins** that **act as catalysts**, **speeding** **up** **biochemical reactions**. **They work** by **lowering** **the activation energy of the reaction**. - **Experimental** vs. **Control Plates**: The Experimental Plate has the variable **being** tested (Bacteria producing enzymes), while the Control Plate **lacks** this variable to **serve** as a **baseline for comparison**. **Definitions**: - **Genes**: **Segments of DNA** that **encode** for **Proteins**. - **DNA**: The **molecule** that carries genetic information. - **Genome**: The complete set of genetic material in an organism. **Number of Genes**: Humans have roughly **20,000-25,000** genes. **Protein-Coding Percentage**: **1-2%** of the human genome codes for proteins. - **Transcription**: The process of converting DNA **into** messenger RNA (mRNA) - **Translation**: The process of **synthesizing** proteins **from** mRNA at the **ribosome** **Exercise 8: Isolating a Mutation** **Results Explanation**: - Results will vary based on the specific experiment. **Look** for indicators of **successful mutation isolation**, such as **changes in antibiotic resistance**. **Key Terms**: - **Conjugation**: The process by which bacteria transfer genetic material through direct contact. - **Antibiotic Resistance**: The ability of bacteria to **survive** despite the presence of antibiotics, often due to mutations **or** acquired genes. - **Plasmid**: A **small**, **circular** DNA molecule **independent** of chromosomal DNA, often **carrying genes for Antibiotic Resistance**. - **Zone of Inhibition**: The area **around an antibiotic disk** **where** bacterial growth is **prevented**, **indicating sensitivity to the antibiotic**. - **Pinpoint Colony**: A small, distinct colony of bacteria on a plate, often **representing** a **single** **bacterium** that has **multiplied**. **Lab Exam I** Study Color Guide Yellow -- PowerPoint Topic \| Red -- Important \| Green -- Answer \| Blue -- Example \| **Bold** -- **Urgent**