11DP Biology Mid-Year Exam Study Guide (HL/SL) PDF

Study Guide for 11DP Biology Mid-Year Exam (HL/SL - same exam) NOTE: Do not rely on this study guide ONLY for your exam. You need to study all lessons and review everything, especially old exams and quizzes done in class. 1. DNA Structure and Function Key Ideas: ○ DNA has a doub...

Study Guide for 11DP Biology Mid-Year Exam (HL/SL - same exam) NOTE: Do not rely on this study guide ONLY for your exam. You need to study all lessons and review everything, especially old exams and quizzes done in class. 1. DNA Structure and Function Key Ideas: ○ DNA has a double-helix structure. ○ The backbone is made of alternating sugar (deoxyribose) and phosphate molecules. ○ Nitrogenous bases pair as follows: adenine (A) with thymine (T), and cytosine (C) with guanine (G). ○ DNA strands are antiparallel (one runs 5' to 3', the other 3' to 5'). ○ Hydrogen bonds hold complementary bases together. Vocabulary: ○ Nucleotide: Basic unit of DNA. ○ Base Pairing: A-T and C-G. ○ Antiparallel: Opposite directions of DNA strands. ○ Hydrogen Bond: Weak bond between bases. 2. Cell Structure and Organelles Key Ideas: ○ Prokaryotic cells lack a nucleus and membrane-bound organelles. ○ Eukaryotic cells are compartmentalized, with organelles like the nucleus, mitochondria, and Golgi apparatus. ○ Key organelle functions: Ribosomes: Protein synthesis. Golgi Apparatus: Modifies and packages proteins. Lysosomes: Digests macromolecules and debris. Mitochondria: ATP production via cellular respiration. Vocabulary: ○ Prokaryote/Eukaryote: Types of cells. ○ Organelle: Specialized cell structure. ○ Cytoplasm: Jelly-like fluid where reactions occur. 3. Membrane Structure and Transport Key Ideas: ○ The fluid mosaic model: phospholipid bilayer with embedded proteins. ○ Transport methods:  Passive Transport: Diffusion, osmosis, facilitated (no energy required). Active Transport: Requires energy (e.g., protein pumps). Endocytosis/Exocytosis: Materials move into/out of cells via vesicles. ○ Hydrophilic substances attract water; hydrophobic substances repel water. Vocabulary: ○ Phospholipid: Molecule forming the bilayer. ○ Osmosis: Movement of water from high to low water potential. ○ Protein Pump: Active transport protein. ○ Hypotonic/Hypertonic: Water movement into or out of cells. 4. Stem Cells and Cell Differentiation Key Ideas: ○ Stem cells can divide and differentiate into specialized cells. ○ Types of stem cells: Totipotent: Can form all cell types (including placental/embryo). Pluripotent: Can form most cell types (except placental/embryo). Multipotent: Can form a limited range of cells (e.g., blood cells). ○ Stem cells are key in growth, repair, and medical therapies. Vocabulary: ○ Specialization: Development into specific cell types. ○ Differentiation: Process by which cells become specialized. ○ Therapeutic Cloning: Producing stem cells for treatment. 5. Enzymes and Proteins Key Ideas: ○ Proteins are made of amino acids linked by peptide bonds. ○ Protein denaturation occurs due to temperature, pH, or mechanical stress. ○ Enzymes speed up chemical reactions and lower activation energy. ○ Peptide bonds form during condensation reactions. Vocabulary: ○ Peptide Bond: Link between amino acids. ○ Denaturation: Loss of protein structure/function. ○ Active Site: Region of an enzyme that binds substrates. 6. Water and Its Properties Key Ideas: ○ Water is a polar molecule, forming hydrogen bonds.  ○ Properties of water: cohesion, adhesion, and high heat capacity. ○ High latent heat of vaporization, Universal solvent, Density anomaly (ice is less dense than liquid water), Transparency, High surface tension, Capillary action ○ Hydrophilic substances dissolve in water, while hydrophobic substances do not. Vocabulary: ○ Cohesion: Water molecules sticking together. ○ Adhesion: Water sticking to other substances. ○ Polar: Uneven charge distribution in a molecule. 7. Experimental Techniques and Skills Key Ideas: ○ Centrifugation separates substances based on density. ○ Hypotonic solutions cause cells to swell; hypertonic solutions cause them to shrink. ○ Use diagrams to label prokaryotic cells, plasma membranes, and organelles. ○ Data interpretation and evaluation are crucial for experimental analysis. Vocabulary: ○ Centrifugation: Separation technique. ○ Hypotonic: Lower solute concentration outside the cell. ○ Hypertonic: Higher solute concentration outside the cell. Paper 2: Key Areas to Master 1. Secretory Cell and Organelle Functions Content to Master: ○ Structure and function of organelles involved in protein synthesis and secretion: Ribosomes: Synthesis of polypeptide chains. Rough Endoplasmic Reticulum: Modifies and folds polypeptides. Golgi Apparatus: Processes and packages proteins into vesicles for secretion. Vesicles: Transports proteins within and out of the cell. ○ Transport mechanisms: Exocytosis (active transport mechanism for releasing proteins). ○ Advantages of cell compartmentalization: Efficient separation of incompatible reactions. Increases efficiency by localizing enzymes and substrates. Skills to Practice: ○ Label and describe organelles involved in secretion. ○ Explain protein production and transport within a cell. ○ Outline the advantages of compartmentalized organelles. 2. Types of Stem Cells  Content to Master: ○ Definitions and differences between: Totipotent Stem Cells: Can differentiate into all cell types, including placental cells. Pluripotent Stem Cells: Can differentiate into most cell types (e.g., embryonic stem cells). Multipotent Stem Cells: Can differentiate into a limited range of cell types (e.g., blood cells). ○ Real-world applications of stem cells in medicine (e.g., regenerative therapies). Skills to Practice: ○ Compare and contrast totipotent, pluripotent, and multipotent stem cells (e.g., differentiation potential and source). ○ Provide examples of how different stem cells are used in therapies. 3. Osmosis and Water Potential Content to Master: ○ Why water moves from high to low water potential (osmosis principles). ○ Effects of osmosis on plant and animal cells: Plant Cells in Hypotonic Solutions: Become turgid (cell wall prevents bursting). Animal Cells in Hypotonic Solutions: Burst (no cell wall). Plant and Animal Cells in Hypertonic Solutions: Shrink (plasmolysis in plants, crenation in animals). Skills to Practice: ○ Explain the behavior of water across membranes in terms of solute concentration and water potential. ○ Compare and contrast osmosis effects in plant vs. animal cells. 4. Fluid Mosaic Model Content to Master: ○ Components of the plasma membrane: Phospholipid bilayer: Hydrophilic heads and hydrophobic tails. Proteins: Integral (e.g., pumps, channels) and peripheral proteins. Cholesterol: Stabilizes membrane fluidity. Carbohydrates: Attached to proteins or lipids (glycoproteins, glycolipids) for cell recognition. Skills to Practice: ○ Draw and label a diagram of the fluid mosaic model. ○ Explain the role of each component in maintaining membrane function. 5. Protein Structure and Denaturation Content to Master: ○ Amino acid structure: Unique R group (side chain) determines chemical properties.  Amino and carboxyl groups. Central alpha carbon atom ○ Formation of peptide bonds through condensation reactions. ○ Causes of protein denaturation: High temperature, extreme pH, or mechanical stress. ○ Effects of denaturation: Loss of tertiary/quaternary structure and function. Skills to Practice: ○ Identify and label parts of an amino acid. ○ Calculate peptide bonds in a polypeptide with a given number of amino acids. ○ Describe denaturation causes and effects in detail. 6. Data Interpretation and Experimental Design Content to Master: ○ Key functions of life (e.g., metabolism, excretion) as demonstrated by experimental data. ○ Analysis of diagrams or graphs related to: Osmosis experiments with animal/plant cells. Enzyme activity under varying conditions (e.g., temperature or pH). Skills to Practice: ○ Analyze experimental data and draw logical conclusions. ○ Justify findings using biological principles. Vocabulary to Memorize for Paper 2 Exocytosis: Active transport mechanism for releasing substances from cells. Compartmentalization: Division of cellular processes within organelles. Water Potential: Measure of water's ability to move across membranes. Turgid/Plasmolysis: States of plant cells in hypotonic/hypertonic solutions. Peptide Bond: Link between amino acids. Denaturation: Loss of protein structure and function. Hydrophilic/Hydrophobic: Affinity or repulsion to water. Diagrams to Practice for Paper 2 1. Internal and external structures of a prokaryotic cell and eukaryotic cell. 2. Labeled diagram of the fluid mosaic model of the plasma membrane. 3. Amino acid structure with labeled functional groups (amino group, carboxyl group, R group). 4. Osmosis scenarios with plant and animal cells in hypotonic and hypertonic solutions.