. List three organelles bounded by a single membrane and three bounded by a double membrane. 2. Define cell signalling. Describe the pathway of a protein signal from outside to inside the cell. 3. Differentiate between prokaryotic and eukaryotic cells with diagrams. 4. Define stem cells. What are the advantages of using stem cells? 5. Categorize different types of stem cells. 6. Evaluate the advantages and disadvantages of induced Pluripotent Stem Cells (iPSCs). 7. Explain four membrane transport mechanisms with diagrams (simple diffusion, facilitated diffusion, osmosis, active transport). MADE BY HADI 8. 9. 10. Describe endocytosis and exocytosis with diagrams. Write the chemical structure of a single phospholipid. Identify the ultrastructure of animal and plant cells. LONG QUESTIONS (6 MARKS EACH) 1. Explain the structure and composition of the fluid mosaic model of the plasma membrane with a labelled diagram. 2. Describe the structure and functions of the following subcellular organelles: mitochondria, nucleus, chloroplast, Golgi apparatus, rough and smooth ER, lysosomes, ribosome
| Q | Topic | Marks |
|---|---|---|
| Q1 | Single vs double membrane organelles | 3 |
| Q2 | Cell signalling + protein signal pathway | 3 |
| Q3 | Prokaryotic vs eukaryotic cells with diagrams | 3 |
| Q4 | Stem cell definition + advantages | 3 |
| Q5 | Categories of stem cells (by potency and origin) | 3 |
| Q6 | iPSC advantages and disadvantages | 3 |
| Q7 | 4 membrane transport mechanisms with diagrams | 3 |
| Q8 | Endocytosis and exocytosis with diagrams | 3 |
| Q9 | Phospholipid chemical structure | 3 |
| Q10 | Animal and plant cell ultrastructure | 3 |
| L1 | Fluid mosaic model - structure, composition, labelled diagram | 6 |
| L2 | Organelle ultrastructure and functions (all 7 organelles) | 6 |
- Single membrane: Lysosome, ER, Golgi, vacuole, peroxisome
- Double membrane: Nucleus, mitochondria, chloroplast
- Active transport is the only process that uses ATP and moves substances against their gradient
- Osmosis specifically refers to water movement; aquaporins are the water channels
- iPSCs were discovered by Yamanaka (2006); the main risk is tumourigenicity from c-Myc oncogene
- The fluid mosaic model (Singer & Nicolson, 1972) features lateral fluidity, membrane asymmetry, and lipid rafts
- Ribosomes are the only organelle with no membrane whatsoever