It is highly important that instructions are followed. I cannot stress this enough! Photos must be taken in the beginning, during and at the end. A clock or timer must but used and in the photos are time reference and the cue card (shown in the instructions). I will give the writer my name once they get the assignment.
Final Lab Manual BIO100A This manual was adapted from Online BIO100A – Survey of Laboratory Manual Version 4.0 by Michael Maxwell and Omar Clay. Report Instructions ljd 1. Conduct the experiment by following the detailed instructions below. (Experiment instructions start on page 6.) 2. Fill out the tables and answers the questions below to guide your experiment and organize your results and conclusions. 3. Take pictures of your experiment prior to beginning once you have all of your equipment set up, in the middle of the experiment and at the end of the experiment. You must include a card like the example below in each photo or you will receive 0 points for the lab report. 4. Record your detailed observations and results throughout the experiment. 5. Once you have conducted the experiment and completed the questions/tables, write a 3 page lab report in essay format (MLA) summarizing the experiment, results and conclusions. See the grading rubric in the LMS. On the next page you will find the materials you will need! Materials Needed ljd · Measuring cup · Measuring spoon · Water Experiment 1 · Red food coloring · Blue food coloring · Salt · Celery stalk Experiment 2 · Radish or other quick sprouting seeds (beans, pepper) · Paper towels · Salt · Zip lock bags or saran wrap · Six cups · Background Information ljdthisfs Introduction: The abiotic (non-biological) features of an ecosystem (e.g., climate, soil quality, water availability) are important to understanding the biological community that comprises the biotic component of an ecosystem. Water availability is particularly important to all life. Freshwater makes up about one percent of the world's water. Figure 6.1). Fresh water scarcity limits the range of many terrestrial species of plants and animals. Plants, like animals, have different tolerances to salt in their environment. All soils have some water-soluble salts, and essential plant nutrients are absorbed in this form. High salinity in the soil (the salt content) makes it more difficult for plants to extract water from the soil. Fresh water enters an ecosystem in the form of precipitation, a river or lake, or an underground aquifer (Figure 6.2). With human population growth, intensive agricultural practices and urban water demand, water levels in many of the world's aquifers are dropping. If fresh water is pumped out of an aquifer at a rate exceeding its natural recharge rate (from precipitation and underground water channels) salt water and other pollutants may intrude into the traditional aquifer basin. Salt water encroachment is a growing problem in the aquifers of coastal communities. Salty soil is also a problem that can arise in agriculture. As irrigation water is absorbed by plants and evaporated by the sun, salts are left behind. Over time, salt may accumulate such that the soil becomes too salty for many plants to grow. It is believed that the ancient population of Sumeria first thrived with its practice of irrigation, but over many generations began to suffer reduced crop yields due to the increasing salinity of the soil. Experiment instructions are next!! Experiment 1 Instructions: Water Transport & Salinity ljdthisfs 1. Obtain four cups and fill each cup with 400 ml of tap water. Use red dye to darkly stain two cups, and use blue dye to darkly stain the other two cups. Be sure that each red cup gets the same amount of dye and that each blue cup gets the same amount of dye. Record the drops in each. Add a spoonful of salt into each cup. 2. Label one red dye cup and one blue dye cup with an S (high salt). Add 4 spoonfuls of salt to each of these cups. Stir the solutions thoroughly. 3. Obtain two similar stalks of celery, each with some leaves at the top. Cut a 1-cm piece (about one-half inch) off the bottom of each stalk. Keep the relative lengths of the two stalks as similar as possible. 4. Carefully, split the stalks up the middle about half-way. The stalks should each now have two “legs.” Be sure that the legs of each stock are similar sized (i.e., the left leg and right leg are the nearly the same length and width). 5. Place the red S cup and the blue S cup together. Gently place one “leg” of one stalk into the red S cup, and the other “leg” of the stock into the blue S cup. The celery should now be “straddling” the two S cups (Figure 5.2.B). Place the red non-S cup and blue non-S cup together and situate the legs of the other celery stalk into each cup (i.e., the celery "straddles" these two non-S cups). 6. Record the time at which you place each celery into the pairs of cups as "Start time." 1. 7. Let the celery sit in the cups for 6 hours, or until you can see color in the leaves of one of the stalks. In Step 6 above, record the time when you remove the stalks as "Stop time." 8. Examine the top of the celery stalks. Are there differences between the celery in the high salt (S) and low salt (non-S) water conditions? Record your observations 9. Remove the celery from the cups (be sure to keep it clear which came from the high salt solution (S) and which came from the low salt (non-S) condition). Lay each stalk out flat. Starting at the top, move down the stalk, making cross-sectional cuts. Stop when you first see evidence of dye. Measure how far up each stalk the red and blue dyes climbed. In Table 6.1, record the distance (cm) traveled by the red dye in high salt conditions (S), the blue dye in high salt conditions (S), the red dye in low salt conditions (non-S) and the blue dye in low salt conditions (non-S). 10. Tear apart the celery stalk. Notice the feel of the vascular tissue, and how the food coloring lies within it. Experiment 2 Instructions: Seed Germination & Environmental Conditions ljdthisfs In this experiment, you will investigate germination of radish seeds in environments with different salt contents. You will prepare six germinating environments and monitor them over four days. Each germinating environment will be a plastic-encased, water-soaked paper towel. 1. To prepare solutions of different salinity, collect 6 clean cups and label them: “1/2”, “1/4”, “1/8”, “1/16”, “1/32”, and “0”. 2. Use a measuring spoon to add salt to 50 ml of water in a measuring cup (about ¼ cup). Add 1.5 tablespoons of table salt (sodium chloride). Stir the water while adding the salt. The solubility of sodium chloride is ~36 grams per 100 mL of fresh water at 25 C. After vigorous stirring the solution you should still be able to see some remaining some salt crystals at the bottom of your solution. This indicates that you have reached the saturation point of salt in your water. 3. Pour off 40 ml of salt water into the cup labeled '1/2." Do not pour the un-dissolved salt. The “1/2” cup will then contain your saturated salt water solution. 4. Clean your measuring cup, and fill each of the remaining cups with 40 ml of plain water. 5. Add 40 ml of plain water to your salt solution in the "1/2" cup. You will then have 80 ml of a 50% saturated saline solution in the “1/2” cup. 6. Using your measuring cup as an intermediate, transfer 40 ml the 50% saturated solution ("1/2" cup) to the cup labeled “1/4”. The “1/4” cup will then hold 80 ml of a 25% saturated saline solution. 7. Using your clean measuring cup as an intermediate, transfer 40 ml the 25% saturated solution (“1/4” cup) to the cup labeled “1/8”. The “1/8” cup will then hold 80 ml of a 12.5% saturated saline solution. 8. Using your clean measuring cup as an intermediate, transfer 40 ml the 12.5% saturated solution (“1/8” cup) to the cup labeled “1/16”. The “1/16” cup will then hold 80 ml of a 6.3% saturated saline solution. 9. Using your clean measuring cup as an intermediate, transfer 40 ml the 6.3% saturated solution (“1/16” cup) to the cup labeled “1/32”. The “1/32” cup will then hold 80 ml of a 3.1% saturated saline solution. You have now prepared a pure water solution in cup “0” and a 3.1%, 6.3%, 12.5%, 25%, and a 50% saturated saline solution in cups “1/32”,”1/16”, “1/8”,”1/4”, and “1/2” respectively. See diagram below. 10. You have six solutions ranging in concentration from 0% to a 50% saturated saline solution. You can run this experiment using each solution as the basis for a germinating environment and following the instructions as they stand. However, if you would like to discard one or two of the salt water solutions and use two solutions of your own design in their place, this is OK. Examples include using water with additives such as sugar, alcohol, soda, or bleach, or even running two at the same salt concentration to get a sense of the uncertainty. You can also use the above protocol to test the effects of even smaller salt concentrations. If you choose to run some alternatives, you still need to run pure water and at least three of the saline solutions, thus all of the rest of the salt concentration experiment still applies. If you do choose to run some alternatives, simply follow the directions below with the relevant change in mind. In the lab report, you will need to describe your alternative experiment(s) and their outcome(s) separately. Have fun! 11. Prepare for seed germination. Take three paper towels and cut them in half. Fold each half towel in half. These towels will be the seeds' germinating environment. 12. Place a folded towel in each of the cups containing your salt solutions and possible alternatives. Make sure that each towel gets soaked with the solution and that you do not lose track of which one is which condition. Label one corner of each towel with the corresponding solution (e.g., "1/2", "1/4", etc.). 13. Count out six piles of 15 or more radish seeds each. Make sure that each pile has the same number of seeds. If there are visible quality differences between seeds make sure that each pile has similar quality as well (e.g., discard cracked, broken, or discolored seeds). 14. Remove the soaked towels from the cups and lay the seeds from each pile out in each one of the towels (Figure 6.3). Be careful not to mix up which towel came from which cup. Record the