Chloroplast and Mitochondria Practice Key

Chloroplasts and Mitochondria Plant cells and some Algae contain an organelle called the chloroplast. The chloroplast allows plants to harvest energy from sunlight to carry on a process known as Photosynthesis. Specialized pigments in the chloroplast (including the common green pigment chlorophyll) absorb sunlight and use this energy to combine carbon dioxide and water and make GLUCOSE and OXYGEN. The complete the chemical reaction for Photosynthesis is: 6 CO2 + 6 H2O + energy (from sunlight) C6H12O6 + 6 02 RAW MATERIALS ENERGY PRODUCTS In this way, plant cells manufacture glucose and other carbohydrates that they can store for later use. Photosynthetic cells found mainly in the leaves may have thousands of chloroplasts. QUESTIONS: 1. What type of cells contains chloroplasts? Plant & some algae 2. What is the energy autotrophs use to make their own food? Sunlight 3. The food making process is called photosynthesis 4. What are the raw materials for photosynthesis? CO2 + H2O 5. What simple sugar is produced? glucos e 6. What gas is USED? CO2 RELEASED? 02 7. Where are most photosynthetic cells in plants found? leaves 8. About how many chloroplasts can be found in photosynthetic cells? thousands Chloroplasts are double membrane organelles with a smooth outer membrane and an inner membrane folded into disc-shaped sacs called thylakoids. Color and label the outer membrane light green. Thylakoids, containing chlorophyll and other accessory pigments (red, orange, yellow, brown), are in stacks called granum (grana, plural). Color and label the grana (STACK) dark green in Figure 1. Grana are connected to each other by structures called lamellae, and they are surrounded by a gel-like material called stroma. Color and label the lamellae brown in figure 1. Color and label the stroma light blue in Figure 1. FIGURE 1-CHLOROPLAST 9. How many membranes surround a chloroplast? 2 10. The outer membrane is smooth 11. The INDIVIDUAL SACS formed by the inner membrane are called INDIVIDUAL pancakes and are arranged in like 12. What pigment is found inside a thylakoid? What color will it be? Chlorophyll, green 13. Other pigments that trap sunlight are called Accessory pigments. What colors are these pigments? red red, orange, yellow, brown 2 14. STACKS of thylakoids are called G (plural) or Stacks orginal are cted to 15. Stacks or grana are connected to each other by Light-capturing pigments in the grana are organized into photosystems. On Figure 2, color and label a single thylakoid (SINGLE DISK) dark green. In figure 2, color and label a granum (STACK) red. FIGURE 2-THYLAKOID Mitochondria are the powerhouses of the cell because they "burn" or break the chemical bonds of glucose to release energy to do work in a cell. Remember that this energy originally came from the sun and was stored in chemical bonds by plants during photosynthesis. Glucose and other carbohydrates made by plants during photosynthesis are broken down by the process of aerobic cellular respiration (requires oxygen) in the mitochondria of the cell. This releases energy (ATP) for the cell. The more active a cell (such as a muscle cell), the more mitochondria it will have. The mitochondria are bout the size of a bacterial cell and are often peanut-shaped. Mitochondria have their own DNA and a double membrane like the nucleus and chloroplast. The outer membrane is smooth, while the inner membrane is convoluted into folds called cristae in order to increase the surface area. 3