Welcome to your OCR AS Biology 1 1. The enzyme responsible for forming hydrogen bonds during the process of DNA replication. DNA helicase DNA polymerase Lactase DNA ligase2. In complex multicellular organisms, eukaryotic cells become _________ for specific functions. Bigger Smaller Turgid Specialised3. Select the incorrect statement regarding haemoglobin. Haem group is responsible for the color of haemoglobin. Each polypeptide chain of haemoglobin contains a haem group. Haemoglobin does not contain a prosthetic group. Each haem group contains an iron atom.4. What happens when a Biuret reagent is added to a solution of free amino acids? The solution turns brick red. The solution remains blue. The solution turns milky white. The solution turns mauve/purple.5. How many oxygen molecules at a time could be carried by a haemoglobin molecule? 4 1 3 26. Many prokaryotic cells do not have __________________. One or more plasmids Microtubules One or more flagella A capsule surrounding the cell7. Prokaryotic cells have a cell wall that contains ________. Cellulose Murein Hemicellulose Pectin8. The most common protein found in animals. Collagen Albumin Haemoglobin Keratin9. Which organelle is referred as the 'Powerhouse of the cell'? Nucleus Ribosomes Cytoplasm Mitochondria10. Network of tiny tubes within the cytoplasm. Cytosol Vacuole Cytoskeleton Plasmids11. Prokaryotic cells have a single ___________ instead of a nucleus. Circular DNA molecule Capsule Cell membrane Flagellum12. Which is not a virus among the following? Bacteriophage Salmonella HIV Influenza13. Which of the following is a double membrane bound organelle? Lysosomes Peroxisomes Chloroplast Ribosomes14. Which of the following solutions turn milky white upon adding ethanol and water? a) A slice of potato b) Milk c) Palm oil d) A piece of apple a & b only None a, b & c b & c only15. Which indicates an indirect evidence for evolution? Addition of extra features in cells. Presence of basic features in cells. The fact that all cells arise from other cells. Existance of all life on Earth as cells.16. Component of plant cell wall. Hemicellulose Pectin Lignin Cellulose17. How many oxygen molecules at a time could be carried by a haemoglobin molecule? 3 2 4 118. Which is not a function of golgi bodies? Packaging macromolecules for delivery to other organelles. Intracellular digestion Determining which proteins are to be transported outside the cell. Sorting and processing proteins.19. The site of ribosome formation. Endoplasmic reticulum Vacuole Nucleolus CytoplasmTime is Up!