Cell Structure and Function Pre-lab Questions

Cell Structure and Function PRE-LAB QUESTIONS 1. What are the functional requirements of life? Movement, Responsiveness, Respiration/Metabolism, Reproduction, Excretion 2. Using Table 1, identify the major similarities and differences between prokaryotic and eukaryotic cells. Similarities: Ribosomes, DNA, Cytoplasm, Cell Membranes Differences: Nucleus and Membrane-bond organelles. 3. Where is DNA housed in a prokaryotic cell? Where is it housed in a eukaryotic cell? Prokaryotic: Cytoplasm Eukaryotic: Nucleus 4. Compare and contrast the role of secretory vesicles, the lysosome, and the peroxisome. Secretory Vesicle: Composed in sac freed pinched off Golgi body and transports proteins and lipids to the plasma membrane Lysosome: Also released from the Golgi body and contains enzymes used to digest components. Peroxisome: Responsible for the breakdown of lipids, amino acids, and hydrogen peroxide, a toxic byproduct of certain cellular reactions. 5. Identify three structures that provide support and protection in a eukaryotic cell. Cell membrane, cell wall, and the cytoskeleton Cell Structure and Function EXPERIMENT 1: CELL STRUCTURE AND FUNCTION Post-Lab Questions 1. Identify A and B in the slide image below. Onion root tip, 1000x. A: __Chromosome____________________ B: __Nucleus____________________ Cell Structure and Function 2. What components of the eukaryotic cell were visible in the onion root tip? Which components were not? Why do you think some components were more visible than others? You were able to see the chromosomes, cytoplasm, cell wall and the nucleus. Was not able to see the mitochondria, ribosomes, rough and smooth endoplasmic reticulum, centrioles and Golgi body. The reason why I think that some components are more visible is because they are too small to be seen under the light microscope. 3. In this experiment, you observed onion root tip cells. What structure could be observed in these cells that would not be observed in a human cell? Cell walls can be observed in an onion root tip but not in a human cell. 4. Would an animal cell be able to survive without mitochondria? Why or why not? The animal would not be able to perform cellular respiration and would not be able to convert food energy into ATP. Cell Structure and Function EXPERIMENT 2: EXPLORING CELL SIZE Data Tables Table 2: Results From Surface Area-To-Volume Experiment Block Dimensions Surface Area (cm2) Volume (cm3) Time Required for Complete Color Change Distance of Diffusion 1 cm × 1 cm × 1 cm 6cm^2 1cm^3 Did not completely color change 0.42cm 1 cm × 2 cm × 2 cm 16cm^2 4cm^3 Did not completely color change 0.4cm 1 cm × 1 cm × 6 cm 26cm^2 6cm^3 Did not completely color change 0.4cm Post-Lab Questions 1. How did the surface area affect diffusion from the block? What about volume? What about the surface area-to-volume ratio? The larger the surface area, the longer it took for diffusion. Volume also had a positive correlation with time for diffusion As volume in the cubes increased, the percentage of diffusion decreased. As surface area to volume decreased, the time required for diffusion increases. 2. Which factor had the greatest effect on diffusion from the block? The greatest factor that affected diffusion was the size of the block. 3. How does this experiment demonstrate the need for cells to maintain a smaller size? Cell Structure and Function This experiment demonstrates the need for cells to maintain a smaller size because if our cells were too big and the surface area could not effectively support the volume of the cell, it will divide to maintain a smaller size. 4. Determine the surface area, volume, and surface area-to-volume ratio for the three blocks below. Then, state which block would be the most ideal cellular morphology. Why? Block 1: Surface area: 13.5cm^2 Volume: 3.375cm^3 Surface Area to Volume: 4 Block 2: Surface Area: 12.5cm^2 Volume: 1.5cm^3 Surface Area to Volume: 8.333 Block 3: Surface Area: 32cm^2 Volume: 12cm^3 Surface Area to Volume: 2.667 The Second block would be the most ideal cellular morphology because it has the highest surface area to volume ration. Cell Structure and Function ©eScience Labs, 2016