Photosynthesis cellular respiration



Photosynthesis and Cellular Respiration – Understanding the Basics of Bioenergetics and BiosynthesisThis figure shows how plant cells provide the energy needed for biological processes.First, photosynthesis uses the energy in sunlight to make glucose from carbon dioxide and water.Then, in cellular respiration, glucose and oxygen are inputs for reactions that provide the energy to make ATP from ADP and P.Finally, hydrolysis of ATP provides energy in the form needed for many biological processes.1a. Why do plants need to carry out all three of these processes?Explanation of why hydrolysis of ATP is needed:Explanation of why cellular respiration is needed:Explanation of why photosynthesis is needed:1b. Why do animals need to carry out cellular respiration and hydrolysis of ATP, but not photosynthesis?Fill in each blank in questions 2 and 3 with photosynthesis, cellular respiration or hydrolysis of ATP.2a. Photosynthesis produces glucose and oxygen which are inputs for ___________________.2b. Cellular respiration produces carbon dioxide and water which are inputs for _______________.2c. Notice that photosynthesis and cellular respiration make a cycle where the products of each process are input molecules for the other process. Draw an oval around the part of the figure that shows this cycle. 3a. Cellular respiration produces ATP and H2O which are inputs for _________________________.3b. The hydrolysis of ATP produces ADP and P which are inputs for _________________________.3c. Cellular respiration and hydrolysis of ATP make a cycle where the products of each process are inputs for the other process. Draw a rectangle around the part of the figure that shows this cycle. To represent the overall chemical equations for photosynthesis and cellular respiration, you will use 16 rectangles. Divide a sheet of paper into 16 rectangles.For photosynthesis, prepare:four rectangles, each with one of the following: C6H12O6, 6 CO2, 6 H2O, 6 O2; write the name of the molecule represented by each chemical formulatwo rectangles with +one rectangle with ––––→ to represent the chemical reactions of photosynthesisone rectangle with sunlightFor cellular respiration, you will need all of the photosynthesis rectangles except the last, plus:four rectangles, each with one of the following: ~29 ATP, ~29 ADP, ~29 P, ~29 H2Otwo additional rectangles with +one rectangle with ––––→one rectangle with two curved arrows4. Arrange the eight rectangles for photosynthesis to summarize the chemical reactions for photosynthesis. Copy this chemical equation into the top box in this chart.1524045085Photosynthesis00Photosynthesis166116083185Cellular Respiration00Cellular Respiration5a. To show cellular respiration, begin by rearranging the photosynthesis rectangles (except for sunlight) to summarize how glucose and oxygen react to form carbon dioxide and water. 5b. Beneath that, arrange the other rectangles (except for the curved arrows) to summarize how ATP is synthesized from ADP + P. 5c. Replace both straight arrows with the pair of curved arrows to indicate that these two sets of chemical reactions are coupled reactions, with energy transfer from the first energy-releasing reaction to the second energy-consuming reaction. 5d. Copy these chemical equations into the bottom box in the above chart.6. Draw two dashed arrows to show how the products of photosynthesis can be used as the inputs for cellular respiration. Next, draw two dashed arrows to show how two of the products of cellular respiration can be used as the inputs for photosynthesis.7. The sugars produced by photosynthesis are used for two different purposes:Some of the sugar molecules are used for cellular respiration to produce ________ which provides energy for the processes of life.Some of the sugar molecules are used to synthesize other organic molecules for plant growth.Multiple glucose monomers are joined together to make polymers such as starch or cellulose. 8a. Circle one glucose monomer in each polymer in this figure.8b. Put a C next to the location of each unlabeled carbon atom in one glucose monomer in cellulose.9. The sugars produced by photosynthesis can be used to synthesize other organic molecules suchas amino acids, which are the monomers in __________________ .A plant is made up primarily of water and organic molecules (e.g. cellulose and proteins). To grow, plants cells add more water and more organic molecules. After cells increase in size, many of them divide to form more cells, which also contributes to plant growth.10. How does photosynthesis contribute to plant growth? 11a. When a seed sprouts, the starch stored in the seed is broken down to glucose which is used by the growing seedling. Give two reasons why the seedling needs glucose.11b. Does a seedling that is growing underground in the dark give off CO2 ___ or take up CO2 ___?Explain your reasoning.Plant Growth PuzzleBiomass is the weight of the organic molecules in an organism. For plants and many other organisms, biomass = (an organism’s weight) – (the weight of the water in the organism).12a. Match each item in the list on the left with the best match from the list on the right.cellular respiration ___a. can result in decreased biomassphotosynthesis ___b. can result in increased biomass12b. For the process that can decrease biomass, explain where the atoms from the organic molecules go. 12c. For the process that can increase biomass, explain where the atoms in the organic molecules come from.An experimenter kept seeds in petri dishes under three different conditions (shown in the top row of the table below). At the beginning of the experiment each batch of seeds weighed 1.5 grams, which was almost all biomass, since there was very little water in the seeds.After ten days, the seeds that were exposed to water had sprouted to produce plants. To determine the biomass of each batch of seeds/plants, they were dried in an oven overnight (to remove all the water) and then weighed. 13. For each condition in the table below, circle the predicted change in biomass after ten days. Explain why you predict a decrease (↓), no change (→), or increase (↑) in biomass. Condition for each batch of seedsLight, no water94932511197200(seeds didn’t sprout)8585201545200Light, water(seeds sprouted)Water, no light943610211700(seeds sprouted)Predicted change in biomass ↓ → ↑ ↓ → ↑ ↓ → ↑Reason for predicting decrease, no change, or increase in biomass14. Your teacher will show you the results of the experiment. Enter the observed results in this table. For each condition, circle the observed change in biomass after 10 days. (1.46 grams of biomass is not significantly different from the 1.5 g of total mass in each initial batch of seeds.) If any of the observed results differ from your predictions in question 14, explain the biological reasons for the observed results. Condition for each batch of seedsLight, no water (seeds did not sprout)Light, water (seeds sprouted to produce plants)Water, no light (seeds sprouted to produce plants)Observed biomass at 10 days (grams)Observed change in biomass ↓ → ↑ ↓ → ↑ ↓ → ↑If any result did not match your prediction, explain a possible reason for the observed result.Bonus QuestionThis figure summarizes a paradoxical result – after 10 days, the dry seeds had the lowest total mass, but the plants that developed in the dark had the lowest biomass.272034081915Light, water 00Light, water 8790523810000 109728057150Light, no water →lowest volume andlowest total mass00Light, no water →lowest volume andlowest total mass400812049530Water, no light →lowest biomass00Water, no light →lowest biomass15. Explain why the plants that developed in the dark had more total mass, but less biomass than the dry seeds. (Hint: There is very little water in seeds, but about three-quarters of the total mass of an actively growing plant is water.) ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download