The Effects of Caffeine on Daphnia

The dependent variable is pulsation rates of L. variegatus before and after they were in the treatments. The standardized variable of this experiment would be the temperature of the surroundings of the L. variegatus, the three pulsation rates taken for each worm before and after the treatments, and also the amount of time each worm was kept in their respective treatments. The level of treatment for this experiment would be ten because of the six different concentration treatments of caffeine and nicotine along with the four household drugs. The sample size of the experiment differed from some treatments to other. For the three different concentrations of caffeine and nicotine, the sample size was 18 black worms each. The sample size of the control treatment of week 1 was 6 black worms. 12 black worms were used for the control of week 2, decaffeinated coffee and instant coffee. 11 black worms were used for the tea treatment and 15 were used for the tobacco treatment. There were three replications of the pulsation rate readings per worm before and after the treatment. With all this information we were able to get the results we got.

The purpose of this lab was to determine the normal heart rate of a Daphnia Magna and decipher the different effects that various substances had on it. A Daphnia Magna is a species of water fleas and can be located in the Northern United Sates against the coastline of the Atlantic in rocky pools. The water flea’s habitat consists of rivers and streams, temporary pools, lakes and ponds, and brackish water. The Daphnia Magna range from two to five millimeters in length and are shaped like a kidney bean (Elenbaas, Molly). Relating to this lab experiment we learned in class that the normal heart rate is measured anywhere between 60 and 100 beats per minute (BPM). If your resting BPM is measured at a level above the number 100 it is known as Tachycardia. This term indicates that your heart level has exceeded the normal range. Also if your heart rate is indicated below 60 then it is called Bradycardia, which means the heart is beating slower than normal. When your heart rate is affected by a substance in the body it is called a Chronotropic agent. When the heart rate decreases because of a substance or chemical it is called a negative Chronotropic and when it is affected oppositely by increasing it is known as a positive Chronotropic agent. In this experiment we added many different substances to the slide on which the water flea was placed to calculate the increase or decrease in its heart rate due to the ingredients in the substances. The first substance used was

Ectothermic animals are animals whose body temperature is affected by their surroundings. This means that if the environment is cold the animal will be cold. If the environment is warm the animal will be warm. This is because the animal doesn’t have the capability of regulating its body systems to keep a constant body temperature. When an ectothermic animal is cold, its heart rate will lower. When the animal is warmer, the heart rate will raise – as long as the temperature isn’t sufficiently high to harm the animal. (Campbell, 2005)

The isopods used for this experiment range in color from gray to brown and were about 8.5 to 18 mm in length. Each Isopod’s head had one pair of antennae and one pair of antennules, both used to detect sensory stimuli from the environment around the pillbug. Their bodies were made of a hard thorax with seven segments and an abdomen. Each pillbug had seven pairs of legs, one for each segment of its thorax. Pill bugs breathe through gill-like structures and must live in moist places.

Daphnia, also known as water fleas, are small crustaceans about 1mm-5mm long and are part of the freshwater zooplankton (Ebert 2005, Hutchinson 2005 & Clifford 1991). Daphnia can be found in most fresh water habitats such as freshwater springs, ponds and reservoirs and are the predominant food for planktivorous fish. Dapnia are ‘filter feeders’ meaning they feed on small particles suspended in the water which can include algae. It has been found that daphnia tend to migrate to the upper parts of the water at night and return to the lower parts of the water in the day to hide from predators (Ebert 2005) (Hutchinson 2005). Daphnia can reproduce through sexual reproduction and also asexual

This laboratory exercise was performed to visualize the effects of various drugs on the heart rate of Daphnia magna. The four drugs tested consisted of: Lidocaine, Acetylcholine, Caffeine, and Nicotine. These drugs were designed to have an apparent effect on the average heart rate of the Daphnia. The laboratory exercise was divided into two parts and procedures: measuring the basal heart rate of Daphnia, and measuring the drug induced heart rate of Daphnia. In order to measure the basal heart rate, various Daphnia were obtained and observed under a microscope at 40x magnification for two separate trials. Using the same technique, the drug induced heart rate with each drug (Lidocaine, Acetylcholine, Caffeine and Nicotine) was measured and

Referring to the experiment`s hypotheses that the A. franciscana prefers light, temperatures between 20-24 ̊ C, and a basic (pH 8) environment; the results regarding the first treatment, light, were initially vague. According to the experiment results, the A. franciscana did not show a clear preference towards light or dark because both sections contained high concentrations of them; the A. franciscana also strayed from the uncovered section. Several factors may shed light on the results such as the A. franciscanas physical appearance; they possess three light-sensitive eyes that can adjust to both low and high light intensities (Fox, 2001). This means that although they may prefer light they can survive in darker habitats as well; relating back to the experiment the A. franciscana may have been content with wherever they were, resulting in limited movement.

The effects of caffeine and alcohol on daphnia are expressive of whether these substances are harmful or beneficial to the organism. By understanding the results of this experiment, it may also be understood how these substances effect humans. In this study, one daphnia was exposed to increasing levels of alcohol, while the other was exposed to increasing levels of caffeine, each in order to test the hypothesis that when given amounts of caffeine and alcohol, the daphnia will be affected the same way a human would. The effect of each substance was measured by the daphnia’s heart rate one minute after the substance was added. Results reveal that alcohol slows the heart rate, while caffeine increases heart rate. Furthermore, caffeine shows a

The purpose of this experiment was to test the affect of caffeine on the heart rate of Daphnia by observing their behavior and heart rate under a microscope when exposed to different concentrations of caffeine. Caffeine is a stimulant drug used in many energy drinks and causes large amounts of stimulatory neurotransmitters to be released. Therefore, as caffeine is a stimulant drug it was hypothesized that the Daphnia heart rate would increase immensely. Daphnia is a group of microscopic, planktonic crustaceans that are arthropods that measure 1-5 millimeters in length. Daphnia live in multiple aquatic environments such as freshwater lakes, ponds and rivers. “The development of genomic infrastructure coupled with a wide range of phenotypic diversity make Daphnia a versatile model

In this experiment we find how caffeine can affect the heart rate of a culture Daphnia. Heart rate of a living organism’s can vary depending on the individual, age, body size, heart conditions, medication use and even temperature. This report will examine if the caffeine is good or bad for the living organism’s health and body. And discuss about where the caffeine is produced and used in daily life of human beings and on the environment. Daphnia is a water flea used in this experiment because of its genomic infrastructure with wide range of phenotypic diversity. This quality of Daphnia makes them a versatile model for the experiment. Also their transparent body allows the experimenter to visually see how the heart beats and count them under the light microscope during the experiment as required. The heart rate of Daphnia is monitored under different concentration of caffeine solution and the results are shown in a table and a graph. Experiment carried out to locate the effects of caffeine on a heart rate of Daphnia may or may not be a predictor of change in human heart rate under caffeine. The effects of caffeine can also be tested on humans but those experiment involving humans contains high risk, as Daphnia can only live for a short period of time and in nature most of them get eaten within their first few days or weeks of life.

Investigating the Effect of Alcohol on Heartbeat of Daphnia Daphnia are the organisms that are involved in this experiment to find out what effect alcohol has on their heartbeat. It is easy to study the effects of alcohol on the heart of Daphnia as the organ can be easily seen through the transparent body of Daphnia. The number of heartbeats may be counted before submersion in alcohol and after submersion in alcohol to investigate the effect of alcohol. Daphnia belong to the Phylum Arthropoda and are Branchiopoda which belong to the class, Crustacea. Daphnia are invertebrates and also have an exoskeleton, jointed appendages, a dorsal heart and open blood system.

The experiment took place in a laboratory setting, and the first step was obtaining sixty individual Daphnia magna (that were neither adults nor tiny offspring) from a large tank in the lab. These individuals were equally divided into three groups; low density, medium density, and high density. The twenty Daphnia assigned to the low density group were split into four groups of five and pipetted into one of four tubes filled with 10mL of Chlamydomonas algae. The twenty Daphnia assigned to the medium density group were split into two groups of ten and placed into one of two tubes also filled up to 10mL with Chlamydomonas. The final twenty Daphnia were all placed into a single tube filled with 10mL of the algae. In order to avoid suffocation-related

Daphnia are used to test water toxicity, they are a vital part of fresh water ecosystems. They are a food source for smaller fish and invertebrates and considered to be a consumer of algae and bacteria (Elbert, 2005). These small crustaceans range in size from 2-5mm long and are commonly referred to as water fleas. Daphnia belong to the group called Daphniidae, which is a relative of freshwater shrimp. It is easy to see the internal organs of daphnia because of a transparent taco shell like carapace. A carapace is the hard outer part of a shell or covering. A daphnia’s life span can range between 1-56 days. (Elenbaas, 2013; Clare 2002). The comfortable pH level for daphnia is between 7.2 and 8.5 (Clare, 2002).

The concentration of solutes in the bodily fluids of most marine invertebrates is roughly isosmotic to their environment (Raven, 2008). Because there is no osmotic gradient there is no tendency for the net diffusion of water away from the animal’s cells to occur. When a change in salinity occurs some organisms have the ability to maintain a constant internal homeostasis despite these external changes and are known as osmoregulators (Oxford, 2008). Other animals lack this ability and as such are called osmoconformers; their internal osmolarity matches that of their

It doesn’t matter what time it is because caffeine is being gulped down all around the clock. Studies have shown that about 90 percent of North American adults consume caffeine everyday or 300 tons all around the world, because let’s face it whether you have a research paper due tomorrow or just need a wake up call to your morning, many of us lean towards caffeine to give us that extra energy. In which, according to the FDA, the average caffeine consumer will take up to 200 milligrams daily, or about the equivalent drinking 4 cans of soda. We all know that soda is terrible for our body and health, so have you ever wondered the true effects of caffeine to the body?