STEM Education PNG Grade 11 Chemistry Notes

THEMA: BIODIVERSITY

  • Module 1: Ethnobotany

    • Topic 1: Medicinal/ Herbal Plants

    • Definition: Medicinal plants are various plant types used in herbalism for medicinal purposes; a herb is derived from the Latin word herba and refers to any part of the plant (fruit, seed, stem, bark, flower, leaf, stigma, or root).

    • Functions of plants: Plants produce phytochemicals for genetic processes, defence against insects and microbes, and against herbivore feeding.

    • Historical context: Medicinal plants have been used since time immemorial; traditional systems remain widely practised.

    • Societal drivers: Population rise, drug shortages, high drug costs, side effects of synthetic drugs, and resistance to infectious diseases drive interest in plant-derived medicines.

    • Typical medicinal plants cited: Aloe, Tulsi (Ocimum sanctum), Neem, Turmeric, Ginger. Basil (Tulsi) used for medicines, black tea, pooja, etc.

    • Global and historical data: FAO (2002) estimated >50,000 medicinal plants used worldwide; Kew (2016) documented ~30,000 plants with some use, with 17,810 having medicinal use.

    • Pharmacological relevance: Today ~80% of antimicrobial, cardiovascular, immunosuppressive, and anticancer drugs are of plant origin; sales exceeded US$65 billion in 2003.

    • Practical considerations: Herbal products are viewed as natural, often safer and eco-friendly, and locally available; there is a need to promote them to save lives.

    • PNG context: Importance of documenting traditional herbal plants for local communities; herbs are seen as a safety symbol relative to synthetic drugs.

    • Activity/Applications:

      • Mini Project 1: Documentation of medicinal/herbal plants in Papua New Guinea.
      • Tasks: Document traditional/herbal plants in their area; research and compile plant information; maintain documentation records; make the documentation system accessible for future reference.
      • Documentation sections: Title, Background, Methods, Results/Discussions, Conclusion; aim to support PNG communities.
      • Example: An ethnobotanical survey from East Sepik Province documents four dialect regions and compares to other PNG provinces; discusses utilization patterns, previously unreported plants, and the need for consistent databases to facilitate ethnopharmacological analysis.

    • Topic 2: Bioactive Compounds in Plants

    • Definition: Bioactive compounds are those with therapeutic, preventive, toxicological, or immunostimulant activity.

    • Classification: Primary metabolites (common to all organisms) vs. secondary metabolites (species-specific due to evolution).

    • Primary metabolites: proteins, fats, sugars.

    • Secondary metabolites (examples): Terpenes, Phenolic acids, Alkaloids, Flavonoids, Saponins, Tannins.

    • Pharmacological properties by class:

      • Terpenes: Antimicrobial, antiviral, anthelmintic, antibacterial, anticancer, antimalarial, anti-inflammatory.
      • Phenolic acids: Anti-carcinogenic, anti-mutagenic, anti-inflammatory, anti-allergic.
      • Alkaloids: Antispasmodic, antimalarial, analgesic, diuretic, local anesthetic, antihypertensive, antiasthma, anti-malarials, bactericidal.
      • Flavonoids: Antioxidant, cardiovascular protection, anti-inflammatory, hepatoprotective, antiviral, antibacterial.
      • Saponins: Antitumor, antiviral, antifungal, anti-inflammatory, immunostimulant, anti-hypoglycemic, hepatoprotective, anticoagulant, neuroprotective, antioxidant.
      • Tannins: Antioxidant, anti-carcinogenic, diuretics, hemostatic, anti-mutagenic, antiseptic.

    • Plant cyclotides: A new class of plant proteins discovered by Dr. Clement Waine; cyclotides are cyclic (ends joined) proteins, originating in plants; etymology from “cyclic” and “peptide.”

    • Practical activity: Lab exercise involves extracting cyclotides from Violaceae and Fabaceae families and testing against fish or mosquito larvae as targets; includes steps for extraction, buffer preparation, and bioassay observing effects on targets.

    • Figure references: Violaceae and Fabaceae examples provided; stepwise extraction and bioassay protocol outlined (larvae/fish targets, extraction in buffer, observation of responses to crude extract).

    • Topic 3: Examples of Therapeutic Drugs from Plants

    • Antimalarial drugs:

      • Quinine: Derived from Cinchona bark (Cinchona officinalis); traditional use in malaria; tree distributed in South/Central America, Caribbean, western Africa.
      • Artemisinin: Derived from Qing-Hao (Artemisia annua); Tu Youyou and discovery of artemisinin and dihydroartemisinin; contributed to major advances in tropical medicine.

    • Hepatoprotective agents (liver protection):

      • Fructus schisandrae chinensis (Wu-Wei-Zi) extracts shown to reduce ALT and improve hepatitis symptoms; isolation of Schisandrin C; development of bifendate and synthetic intermediate bicyclol; bicyclol approved in 2001 for hepatitis and patented in 15 countries.
      • This case highlights drug discovery from traditional herbal medicine.

    • Other plant-derived drugs: A table of additional plant-derived medicines is mentioned (not fully enumerated in the transcript).

  • Activity: Case Study of Quinine and Artemisinin (Antimalarials)

    • Students research and summarize the discovery of two antimalarial drugs (Quinine and Artemisinin).
    • Objectives: Foster creativity and innovation mindset for future discoveries/inventions.
    • Notes: Students should clearly state sources/references.

  • Additional context from the Ethnobotany section:

    • The World Health Organization and other bodies support ethnopharmacology research and documentation; plant-based medicines play a role in modern drug discovery.

THEMA: BIOTECHNOLOGY

  • Module 1: DNA Analysis and Proteins

    • Topic 1: Polymerase Chain Reaction (PCR)

    • Definition: PCR rapidly makes millions to billions of copies of a specific DNA sample; enables amplification from a very small DNA sample for detailed study.

    • Principle: Primer-mediated enzymatic amplification using DNA polymerase; polymerase extends from a preexisting 3′-OH group to generate double-stranded DNA; primers define the target region.

    • Components and schematic references: DNA template, DNA polymerase, primers, nucleotides.

    • Applications:

      • Anthropology/Evolution: DNA fragments from fossils or deceased individuals can be amplified to determine sex or genetic lineage; example: maternal lineage via mitochondrial DNA showing Denisovan admixture in Papua New Guineans (~7-8% sequence similarity with Denisovans, indicating interbreeding ~14,500–30,000 years ago).
      • Forensics: DNA profiling/typing; identify individuals from crime scenes or suspects; parental testing and paternity; use of real-time qPCR as a benchmark technology for detection of nucleic acids in microbiology and forensic applications.
      • Medical diagnosis: Early disease diagnosis (e.g., for newborns, potential parents with carrier status, cancer predisposition, tissue typing for transplantation); RT-PCR for RNA viruses (e.g., SARS-CoV-2/COVID-19) using reverse transcription to cDNA for PCR amplification; qPCR allows real-time detection.
      • Other notes: Real-time qPCR provides a quantitative measure; PCR on microchips enables high-throughput forensic analysis; mitochondrial DNA (mtDNA) is used in some forensic applications due to high copy number and matrilineal inheritance.

    • Three-step PCR procedure commonly cited: Denaturation (e.g., 94°C, 15–30 s), Annealing (54–60°C, 20–40 s), Extension (72–80°C, often 72°C).

    • Historical/visual references: Figure SC-TRB-02 (PCR amplification schema); Figure SC-TRB-03 (Denisovan heritage); Figure SC-TRB-04 (RT-PCR schematic).

    • Real-time PCR and qPCR notes: Benchmark technology for nucleic acid detection; high-throughput microchips for forensic analysis; various references cited (e.g., Bustin et al. 2012).

    • Topic 2: Dyes in DNA Sequencing

    • Sequencing definition: Determining the sequence of nucleotides (A, T, C, G) in DNA; Sanger sequencing is the well-established method discussed.

    • Sanger sequencing history: Developed by Frederick Sanger in 1977; awarded Nobel Prize in 1980 for chemistry.

    • Labels: Four fluorescent dyes label the 3’ termini of sequencing fragments; different dye colors correspond to bases.

    • Steps overview: Three basic steps of Sanger sequencing (below) with emphasis on chain termination and fragment analysis.

    • Topic 3: Proteins

    • What is a protein? A protein is a macromolecule made of amino acids linked in a chain and folded into a 3D structure; sequence determines function. Central dogma: DNA -> RNA -> Protein.

    • Synthesis: Transcription (DNA to mRNA) in nucleus; translation (mRNA to protein) at ribosome in cytoplasm; tRNA brings amino acids; codons in mRNA dictate amino acid sequence.

    • Functions: Antibodies, enzymes, messengers, structural components, transport/storage.

    • Protein structure levels: Primary, secondary, tertiary, quaternary; structures influence function. Globular vs fibrous shapes.

    • Amino acids: Building blocks; 20 standard amino acids; connected by peptide bonds via dehydration synthesis; R-group determines properties.

    • Glycoproteins: Proteins with carbohydrate attachments (glycans) via glycosylation; roles in cell recognition, signaling, immune function, and structural roles in tissues; examples include HCG, EPO, clotting factors; glycoproteins are surface proteins on cell membranes; glycoproteins influence protein hydrophilicity and function.

    • Case study: Cry proteins from Bacillus thuringiensis used in GMO crops to kill insect pests; Cry2Ah highlighted; Dr. Clement Waine involvement; engineering and commercialization in South America.

    • Cry proteins illustrate biotechnology applications in agriculture and pest control.

    • Cry protein structures: Three-dimensional structures illustrated in Figure SC-BT6.

  • Case study reference: Cry proteins and Dr. Clement Waine’s work with Bt Cry proteins and DuPont in the USA; commercially significant biotechnology application.

THEMA: HEALTH AND MEDICINE

  • Module 1: Biochemistry in Medicine

    • Topic 1: How a Medical Drug Works (Mechanism of Action)

    • What are drugs? Chemicals (excluding food) taken to affect normal body function; beneficial effects denote medicines; harmful effects denote poisons; government approval (e.g., FDA in the USA; WHO for global distribution) is required.

    • Drug classification by MoA:

      • Chemotherapeutic agents: used to cure infectious diseases and cancer (e.g., sulfa drugs, antibiotics).
      • Pharmacodynamic agents: used in non-infectious diseases (cholinergic, adrenergic, hallucinogenic, sedatives).
      • Miscellaneous agents: narcotic analgesics, local anesthetics.

    • Purposes of medical drugs:

      • Diagnosis (e.g., pupil-dilation drops, diagnostic injections).
      • Prevention (e.g., prophylaxis, vaccines intent not stated here but implied).
      • Treatment of symptoms (e.g., analgesics for pain, antipyretics for fever).
      • Cure of disease (e.g., antimicrobial agents that halt infection).

    • How drugs work: Many drugs act by binding target receptors to block or mimic natural ligand function. Agonists activate receptors; antagonists block receptors without triggering a response; receptor antagonists can be reversible or irreversible.

    • Enzyme targets: Some drugs inhibit or activate enzymes to regulate biochemical pathways.

    • Examples:

      • Agonists: Morphine, nicotine, phenylephrine, isoproterenol.
      • Antagonists: Beta-blockers like propranolol (reversible or irreversible depending on mechanism).

    • Mechanism of action examples:

      • Aspirin and NSAIDs: Inhibit cyclooxygenase (COX) pathway, reducing prostaglandin synthesis and inflammation.
      • COX-1 vs COX-2: COX-1 is generally in stomach lining; COX-2 is inducible at inflammation sites; selective COX-2 NSAIDs (e.g., celecoxib) aim to reduce GI side effects.
      • Side effects: Inhibiting COX-1 can irritate the stomach; COX-2 selectivity reduces some side effects but still can have risks.

    • Drug access to active site: Example of membrane diffusion pathway for access to COX-2 active site; celecoxib intercalates into membrane core and diffuses to the hydrophobic site.

    • First-pass effect: Oral drugs undergo hepatic metabolism before reaching systemic circulation, reducing bioavailability.

    • Mechanism of action example exercise: The action of aspirin/NSAIDs via COX inhibition and the consequences of COX-1 vs COX-2 selectivity.

    • Additional MoA concepts: Receptors, dose-response curves, and pharmacodynamics contextualize how drug effects scale with concentration.

    • Topic 2: Drug Pharmacology

    • Drug receptor concept: Drug binding to a receptor yields a pharmacological response; number of receptor-drug complexes correlates with response.

    • Dose-response relationship: Dose (log scale) vs percent maximal effect; full agonist reaches 100% maximal effect; partial agonists achieve less than maximal response even at high doses.

    • Efficacy vs potency:

      • Efficacy: Maximal response a drug can produce.
      • Potency: Dose required to produce a given effect; lower dose for the same effect implies higher potency.

    • First-pass effect: The liver metabolizes many orally administered drugs during first pass from GI tract to the systemic circulation, reducing bioavailability.

    • Drug transport across membranes: Membrane crossing occurs mainly via passive diffusion if the drug is uncharged and lipid-soluble; ionization (affected by pH and pK) influences diffusion.

      • For a weak acid: when pH < pK, HA (non-ionized) predominates; when pH > pK, A− (ionized) predominates.
      • pK is the negative logarithm of the equilibrium constant for the dissociation reaction; the relationship governs ionization states.

    • Pharmacokinetics: Absorption, distribution, metabolism, elimination govern drug levels and effects.

    • Topic 3: Significance of Diagnostic Laboratory Tests

    • Activity: A set of clinical notes focusing on common tests and interpretations.

    • Full Blood Count (FBC):

      • Purpose: Routine starting point for medical investigations; counts of blood cells provide insight into health and disease.
      • Components measured: White blood cells (WBCs), neutrophils, basophils, eosinophils; red blood cells (RBCs), platelets; hemoglobin levels.
      • Interpretation: Normal ranges common; ~5% may have minor abnormalities; abnormal results may indicate specific problems or diseases when symptoms accompany the results.
      • White blood cells: Neutrophils (~40–60% of WBCs) are first responders to bacterial infection; basophils respond to parasites; eosinophils relate to allergies or parasitic infections; elevated eosinophils can indicate allergy/asthma or cancer.
      • Red blood cells: Main function is oxygen transport via hemoglobin; normal hemoglobin for adult men/women set ranges; anemia and polycythemia described as common issues.
      • Platelets: Critical for blood clotting; normal range 150–400 x 10^9/L; risks of thrombocytopenia or thrombocytosis discussed; long periods of immobility or flight travel concerns for thrombocytosis.

    • Liver Function Tests (LFTs):

      • Purpose: Screen for liver infection/disease, monitor disease progression, assess liver’s synthetic and clearance functions, detect enzyme leakage due to liver damage.
      • Key enzymes/proteins and typical interpretations:
      • ALT (alanine transaminase): Elevated with liver damage; normal 7–55 U/L.
      • AST (aspartate transaminase): Elevated with liver or muscle damage; normal 8–48 U/L.
      • ALP (alkaline phosphatase): Elevated with liver or bone disease; normal 40–129 U/L.
      • Albumin and total protein: Low levels suggest liver damage/disease; albumin is essential for infections and other functions.
      • Bilirubin: Elevated levels indicate liver damage, bile flow obstruction, or certain anemias; normal 0.1–1.2 mg/dL.
      • GGT (gamma-glutamyltransferase): Elevated with liver or bile duct damage.
      • LD (lactate dehydrogenase): Elevated with liver damage, but non-specific.
      • PT (prothrombin time): Prolonged in liver damage or with anticoagulant therapy; normal 9.4–12.5 seconds.
      • Note: Values may vary by lab; the listed ranges are typical for adult men.

    • Kidney Function Tests:

      • Urinalysis: Screens for protein and blood in urine; proteinuria can indicate infection, heavy exercise, or kidney disease.
      • Serum creatinine: Assesses renal clearance; elevated creatinine suggests kidney dysfunction; typical thresholds: women >1.2 mg/dL, men >1.4 mg/dL indicate potential problems (approximate values per NKF).
      • Blood Urea Nitrogen (BUN): Measures nitrogenous waste from protein breakdown; high levels can reflect kidney issues but may be influenced by medications or other conditions.
      • Estimated GFR (eGFR): Estimates kidney filtration rate; <60 mL/min/1.73 m^2 can signal kidney disease.

  • The document also lists broader STEM Themen in the introductory pages and notes on the structure of the Chemistry resource book, including: ENERGY, BATTERY TECHNOLOGY, INFORMATION SYSTEM, WASTE MANAGEMENT, EARTH SCIENCES, INFRASTRUCTURE, COMPUTER SCIENCE, ARTIFICIAL INTELLIGENCE, ENTREPRENEURSHIP, and more; these indicate a cross-disciplinary approach to STEM education in PNG.

  • Important cross-cutting concepts and numerical references mentioned in the transcript:

    • Ten thematic areas (Thema) in the Chemistry Teacher Resource Book; only three Thema presented in this booklet: BIODIVERSITY, BIOTECHNOLOGY, HEALTH AND MEDICINE.
    • Biodiversity data: >50,000 medicinal plants used globally (FAO 2002); 17,810 plant species with medicinal use (Kew 2016); ~80% of several drug categories plant-derived; plant-origin drugs sales > US$65 billion in 2003.
    • Denisovan ancestry in PNG: Papua New Guineans share about 7–8% genetic sequences with Denisovans, indicating interbreeding ~14,500–30,000 years ago (mtDNA-based and geographic references).
    • Sanger sequencing: Developed 1977; 4 ddNTPs labeled with dyes; chain-termination mechanism; capillary electrophoresis yields chromatogram; typical read length up to ~900 base pairs for practical purposes in many contexts.
    • PCR cycles: Denaturation at 94°C, annealing at 54–60°C, extension at 72–80°C; RT-PCR variant combines reverse transcription with PCR for RNA templates, producing cDNA.
    • Central dogma: ext{DNA}
      ightarrow ext{RNA}
      ightarrow ext{Protein}
    • DNA structure basics referenced: DNA consists of two strands with a sugar-phosphate backbone; four bases A, T, C, G; nucleotides linked by phosphodiester bonds; base pairing supports double helix structure (conceptual).
    • Protein structure terminology and concepts: Primary, secondary, tertiary, and quaternary structures; globular vs fibrous proteins; glycoproteins and glycosylation; Cry proteins and Bt crops as biotech applications.
    • Mechanisms of drug action basics: Agonists vs antagonists; reversible vs irreversible antagonists; COX-1 vs COX-2 selectivity and implications for side effects; first-pass metabolism concept; membrane diffusion and ionization considerations for drug absorption.

  • Connecting themes to prior knowledge and real-world relevance:

    • Ethnobotany links traditional knowledge to modern pharmacology and drug discovery; modern drug companies have leveraged traditional plants (e.g., Artemisinin) to develop life-saving medicines.
    • PCR and sequencing technologies underpin forensic science, clinical diagnostics, and personalized medicine; real-time qPCR is a standard in diagnostic workflows (e.g., infectious diseases and cancer screening).
    • Understanding protein structure-function relationships underpins drug design, disease mechanisms, and biotechnology applications (e.g., Cry proteins in GM crops).
    • Diagnostic laboratory tests (liver and kidney function, FBC) are essential for monitoring health, guiding therapy, and assessing drug safety and liver/kidney status during treatment.

  • Formulas and key expressions (LaTeX):

    • Central dogma: ext{DNA}
      ightarrow ext{RNA}
      ightarrow ext{Protein}
    • PCR cycle temperatures (typical values): Denaturation: 94^ ext{°C}, 15 ext{-}30~s; Annealing: 54 ext{-}60^ ext{°C}, 20 ext{-}40~s; Extension: 72 ext{-}80^ ext{°C} (commonly 72^ ext{°C}).
    • DNA sequencing basics: Sanger sequencing uses ddNTPs to terminate extension; four dyes label ddNTPs in automated systems; chain-termination strategy yields fragments ending at every nucleotide position.
    • Dideoxynucleotide property: ddNTPs lack the 3'–OH group; once incorporated, extension ceases; the result is termination at that base.
    • Ionization in drug diffusion: For a weak acid, equilibrium between HA and A^- depends on pH relative to pK; if pH < pK, HA predominates; if pH > pK, A^- predominates.
    • Liver metabolism phases: Phase I (introducing polar groups, often via P-450 enzymes) and Phase II (conjugation, e.g., with glucuronic acid or sulfate) to enhance excretion; CYP3A4 metabolizes about 50% of drugs.
    • Kidney excretion steps: Glomerular filtration, proximal tubular secretion, distal tubular reabsorption (ionization state affects reabsorption).

  • References to figures and tables in the text (not reproduced here): PCR schematic (Figure SC-TRB-02), Denisovan ancestry illustration (Figure SC-TRB-03), Sanger sequencing figures (SC-TRB-05 to SC-TRB-09), DNA structure schematic (Figure SC-TRB-07), Sanger chromatogram concept (Figure SC-TRB-09), and other supporting visuals are acknowledged as part of the original resource.

  • Summary of the workbook structure (as context for studying):

    • The workbook is organized into three Thematic Areas (Thema) relevant to Grade 11 STEM Education: BIODIVERSITY, BIOTECHNOLOGY, HEALTH AND MEDICINE, each with modules and three topics. The contents emphasize foundational chemistry concepts, laboratory skills, and real-world applications in medicine, genetics, biotechnology, and pharmacology.