The Effects of Drugs on Daphnia

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The Effects of Drugs on Daphnia Student Study and Analysis Sheet 36W 1258 Pre-Lab Introduction Knowledge - Probe Curiosity Daphnia, often called water fleas, are arthropods, related to crabs,

This allows for observation of their internal organs, it is easy to observe certain life functions in Daphnia.

1 The Effects of Drugs on Daphnia Student Study and Analysis Sheet 36W 1258 Pre-Lab Introduction Knowledge - Probe Curiosity Daphnia, often called water fleas, are arthropods, related to crabs, lobsters, and other crustaceans. One way that they differ from those crustaceans is that their carapace is transparent. This allows for observation of their internal organs, it is easy to observe certain life functions in Daphnia. Perhaps the most dramatic are the move ment of food through the digestive system and the beating of the heart. Besides being able to view the heart actively beating, you will be able to detect changes in heart rate after changing the environment that the Daphnia live in. Chemicals that cause the heart rate to accelerate are called stimulants, those that slow it down are called depressants. Stimulants and depressants are chemicals that are naturally produced by many organisms. Have you ever wondered what causes your heart to speed up when you are afraid and how does it slow back down? There must be some chemical at work here. Besides your natural body chemicals, stimulants and depressants are formed by many other organisms such as plants and fungi. One of the chemicals we will be experimenting with in this activity is a compound called caffeine. This mate rial is found in a multitude of plants and is produced and stored in their leaves, stems, seeds and roots. It comes from a material in plants called caffeic acid. Interesting enough, the function of this material is not exactly known. It is thought that it may have a role in antibacterial and antifungal protections as well as a nat ural insecticide. Another fairly common plant derived substance is nicotine, found in great abundance in tobacco leaves. Again not much is known regarding the exact function of nicotine in plants, although it may have a role in growth regulation. Some chemicals that we use as drugs have no use at all for the organism that manufactures them. Some are actually waste products that are excreted. An example of this would be alcohol. Alcohol, whether you use it to rub on a wound or drink, is a molecule of glucose(c6h1206), they remove the energy and are left with Carbon, Hydrogen and Oxygen. These atoms are reassembled in a new form, molecules of alcohol and CO2. Some of the drugs that we use come directly from humans and other animals. An example of this is epi nepherine, a common hormone in humans that was formerly known as adrenaline. This hormone is some times referred to as the fight or flight hormone. It is produced by the body in times of stress and gets the body ready for trauma. Another function of epinepherine is that it is used as a neurotransmitter. Neurotransmitters are substances that help nerves communicate with each other as they transmit messages from one part of the body to another. In this activity, you will first learn the structures of a living Daphnia and the location of the heart. You will then take the Daphnia and treat it with the chemicals described above. The counting of the rate of heartbeats will allow you to tell if the chemical is a stimulant or a depressant. Copymaster. Permiseon granted to make unlimeed copies for use in any one school buiding. For educational use only, not for commercial use or resale. O 1996 WARD S Natural Saence All rights rfserved

Questions j 1) Observe the diagram of Daphnia included with this kit. What structures do you see that would contribute to the Daphnia being classified as a Crustacean?

$Prediction a 4\c 3) In this activity, we ll be treating Daphnia with caffeine (a substance in coffee and chocolate), nicotine (a substance in tobacco), epinephrine (a hormone produced when someone$

2 Questions j 1) Observe the diagram of Daphnia included with this kit. What structures do you see that would contribute to the Daphnia being classified as a Crustacean? 2 -+ Application 2) One of the extended activities proposed in this lab will be to change the temperature around the Daphnia and view the effect on heart rate. If this experiment were performed on humans, what results would you expect? Explain. Prediction a 4\c 3) In this activity, we ll be treating Daphnia with caffeine (a substance in coffee and chocolate), nicotine (a substance in tobacco), epinephrine (a hormone produced when someone feels threatened), and alcohol. Predict which substances you think will be stimulants and which will be depressants. [Copymastei Permission granted to make unlimited copes lor use in any one school building. For educational use on not for commercial use or resale. V 1996 WARCYS Natural Science

3 Performing the Experiment 3 Objective To learn to identify stimulants and depressants by their effect on the heart rate of Daphnia. 1.J cj ci h Materials Culture of Daphnia magna Daphnia netting Magnification chamber Pipettes Solutions of: Caffeine Epinephrine Ethyl Alcohol Nicotine Unknown samples (optional) Stopwatch or watch with a second hand Daphnia Form and Structure Study Sheet Procedure Self-Direction Mental Stimulation 1) Cut the daphnia netting into small squares and place in the bottom of the magnification chamber. 2) Using a pipette, draw up a few Daphnia from the culture dish, 1 or 2 will suffice. Place the Daphnia in the magnification chamber, on top of the netting, with as little water as you can transfer. This will keep then from swimming rapidly away. 3) Practice observing the Daphnia by holding the cover of the chamber approximately 2 inches above the top of the chamber. Locate a large daphnia and its heartbeat. Use the diagram of Daphnia to locate the heart. 4) Try timing the heart rate. To do this, have your partner start the stopwatch and tell you when to begin counting. Count for 10 seconds. Enter this heart rate in the Data Tables and compute the heart rate per minute by multiplying by 6. 5) Repeat this procedure 2 more times and find the average heart rate of a Daphnia. Enter this information into the data table. 6) Add a drop of caffeine solution to the Daphnia. Wait one minute for the solution to be absorbed, and com pute the average heart rate as performed above. Enter whether caffeine is a stimulant or depressant. 7) After you have computed the caffeine effected heart rate, discard your Daphnia as per your teacher s instructions. Rinse out and dry your chamber and net. 8) Repeat steps 2 through 7 with each of your remaining test solutions and any unknowns that your teacher might include. Copymaster. Permisaon granted to make uqlirated copies for use in any one school building. For educational use only, not for commercial use or resale. C 1996 WARDS Natural Science

(X6) Heart rate/lo sec. 1 Heart rate/lo sec.

$1 observation ata Scv\ na ysis Integrity er Mm.$ sec. ii 21 3f Claim Control Per Miii.

sec. 1 Heart rate/lo sec. if 21 21 31 Control Per Mm.

1 Heart rate/lo sec. 1 2 2 3 3 copymaster.

4 Analysis 4 Data Tables Control Per Mm. (X6) Treated with Caffeine Per Mm. (X6) Heart rate/lo sec. 1 Heart rate/lo sec. ii 21 2j 3J Control l Heart rate/lo sec. 1 observation ata Scv\ na ysis Integrity er Mm. (X6) Treated with Epinephrine Per Mi (X6) Heart rate/lo sec. ii 21 3f Claim Control Per Miii. (X6) Treated with Ethyl Alcohol Per Mi (X6) Heart rate/b sec. 1 Heart rate/lo sec. if Control Per Mm. (X6) Treated with Nicotine Per Mm. (X6) Heart rate/b sec. 1 Heart rate/lo sec copymaster. Permission granted to make unlimited cop for use in arr one school building For educational use only not for commercial use or resale C 1996 WARDS Natural Science

Questions -+ Application 1) Which substances were stimulants, which were depressants? 5 2) Would it be safe to conclude that these materials would act the same way in humans? Explain your answer.

5 Questions -+ Application 1) Which substances were stimulants, which were depressants? 5 2) Would it be safe to conclude that these materials would act the same way in humans? Explain your answer. 3) There are many substances made in the body that act as stimulants and depressants. Propose a situation where your body might need to produce a stimulant. Propose a situation for a natural depressant. 4) Why was it necessary to start with a new Daphnia after each substance? 5) Design an experiment that would test the effect of temperature on the heart rate of Daphnia. + Application Further Investigations Critical Thinking Creative Thinking 1) Design an experiment to test the effects of pollutants on the Daphnia heart rate. Investigate materials such as ph, trying to simulate the ph found in an acid polluted lake. 2) Go out with a small aquarium net to a pond and run it through some weeds along the side. Put the crea tures that you catch into a jar. There should be some Daphnia there. Bring these Daphnia back to the lab and investigate their heart rates. Compare the durability of a wild Daphnia to a lab raised Daphnia. [Copymaster. Permission granted to males untrrsted copies fix use in any one o I school building. For educational use on. not for commercial use or resale WARDS Natural Science

6 VAEI Community of Scientific Practice Level of Inquiry A Process of Scientific Inquiry Socially and Language Rich Habits of Mind (QPOE 2 ) Environment. Habits of Mind components not QPOE 2 components not currently Socially and Language Rich currently included in my lesson design included in my lesson design Environment components not. Changes I will make to include these Changes I will make to include these currently included in my lesson design components components Changes I will make to include these components Openness to New Ideas! Informed Skepticism Question 13 v Culture Supporting Risk Taking I5ercL ed Persistence * Knowledge - Probe pcor 1 Mss tftc ervi rek Collaborative Structures 10 c Explanation * Evidence C Desc Adaptability + Reasoning 50L WV\,\ Cooperative Interactions Id. Skcrt w/ -[Cc I-k& Shared Control Discourse: Oral/Written LlL Negot ated Meaning S

Episode One Debriefing: Teacher Guide

Episode One Debriefing: Teacher Guide ACTIVITY 1: DRUG BEAT In this activity, the student will conduct an experiment to learn how two common drugs affect the heart rate of an invertebrate animal. Background