Frog Ringer Experiment

Three Daphnia magna were placed in a petri dish with a small amount of spring water. Each Daphnia magna was measured separately. The Daphnia magna was placed on a slide and their control heart rate was measured for 15 seconds under the microscope and multiplied by four. Then, it was placed in the epinephrine solution for two minutes.The Daphnia magna was placed back onto the slide with the spring water and the heart rate was measured again for 15 seconds and later multiplied by four to observe the effect of epinephrine on the heart rate. They were then placed into a different petri dish of spring water after their experimental heart rate was recorded. All the heart rate values were placed into a Microsoft Excel document. The controlled variables included the temperature of the water, the time subjected to the epinephrine solution, and the time used for measuring the control heart rate and the epinephrine heart

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

In last procedure, the effect of epinephrine on Daphnia heart rate was observed. The result is posted on figure 5:

In order to complete this exercise, two different procedures were conducted; one measured the basal heart rate, and the other measured the drug-induced heart rate. A sample 's basal heart rate can be defined as the “resting” heart rate. This is when no drugs or altering substances are applied. In comparison, the drug-induced heart rate of a sample can be defined as the heart rate after the drug was administered to the surrounding environment. The four drugs tested on the Daphnia specimens were Acetylcholine, Caffeine,

Table 5. The effects of Atropine measured by the ventricle of the frog’s heart by amplitude, period, and BPMs.

Epinephrine/adrenaline: Heart rate is increased by the sympathetic nervous system and the hormone adrenaline circulating in the blood via activation of cell surface receptors in

Then using a disposable pipette we placed two drops of room temperature water (21 degrees) on top of the Daphnia. Then placing it careful under the microscope with a for 15 seconds using a tally counter and clicked away how many heart beats we observed and did this three times for three trials, in between the times would give the daphnia a two minute recovery period. We then would process the trials information and calculate an average. After the information calculated we then  multiplied our results by four to see the average heart beats per minute with room temperature water. We gave the daphnia five minute to recover then went on to proceed with two drops of hot water (40 degrees celsius) placed on top of the Daphnia using the pipette. Again three trials for 15 second using the tally clicker following after a two minute break. The same followed for the cold water (0 degree celsius) placing two drops on top of the Daphnia administered by pipette. In between the transitional water temperature trials we then cleaned up the excess water before placing new drops of water by gently soaking up the water with kimwipes. After five minutes we tallied the heartbeats of the Daphnia before administering the epinephrine. Then again gently gave two doses of epinephrine using a new pipette. Then after we observed and tallying the heart beats before administering the epinephrine, three times again recording our results then averaging it. Then we placed two drops of the epinephrine on top of the daphnia, tallying the heartbeats and recording and calculating our trial results. Then after two minutes we observed and tallied the effects after the epinephrine had been used.  Each trial again consisted of observation under the microscope, tallying and observing the behavior internally and externally of the

The two drugs that have been used in this experiment to test their effects on the heart rate and depolarization rate of the P wave of the crayfish. Depolarization is defined as the contractions of heart muscle, and it is shown in P wave pattern of the ECG. Comparing the results of the trials of epinephrine drug to the resting state, it shows that this drug increases the heart rate, decreases beat period, and decreases the time that take

When beta-1 receptors are turned on it leads to elevated heart rate and increased contractual force. Beta-blockers are medications used in the treatment of high blood pressure.These medications inhibit the negative effects caused by the sympathetic nervous system on the heart muscle. They act by capping off beta-receptors, and thus inhibit the stimulating affects on the heart caused by adrenaline (Aschenbrenner & Venable, 2012). The medication in-effect lowers blood pressure, by decreasing contractual force on the myocardium and reducing heart beat (Mayo Clinic,

The cardiac muscle cells can be affected by heart disease through the inability to maintain its homeostasis through the calcium pump. If there is excess calcium within the heart it results in the in ability of the heart muscle to relax. As a result, the ADP/ATP ratio increases, phosphocreatine decreases, and energy stores are depleted. Furthermore, this imbalance affects the energy needed to relax the left ventricle. Secondly, diastolic heart failure can occur from changes in preload, afterload, renin-angiotension-aldosterone system, and the sympathetic nervous system. These changes affect the fibrillar collagen within the extracellular matrix that affects the ability of the ventricular to relax. These changes along with those compensatory mechanisms results in continuous resistance that results in increased in left ventricular end-diastolic pressure (McCance & Huether, 2010).

In the presence of excess T3 and T4, an increase in number as well as affinity of beta-adrenergic receptors in the heart is noted. These receptors facilitate the action of "fight, flight and fright" hormones ( epinephrine, norepinephrine) which are positively chronotropic ( beat faster) and inotropic ( pump harder) to the heart. This may then lead to cardiac failure in older patients.

of atria and ventricle. Impulses not being transmitted from atria to the ventricle; no whole number relationship between atrial and ventricular contractions was demonstrated.

Chemicals normally present in the body, blood or interstitial fluid influence the heart rate. “Heart rate, or heart pulse, is the speed of the heartbeat measured by the number of heartbeats per unit of time -typically beats per minute” (Medterms 2012) Substances that increase a heart rate are called stimulants. Substances that decrease the heart rate are called depressants. In this lab the students recorded information on the effects of stimulants and depressants on a Daphne. An example of depressants would be a sleeping pill. For clinical use a lot of consumers take this in order to decrease heart rate and to sleep better. Antianxiety medications affect people who have severe anxiety disorders. “Medications that act as depressants are able to imped this anxiety causing brain activity, thus relieving anxiety symptoms.” (Live strong quote) An example of a stimulant would be adrenaline. Adderall is a great example of a stimulant for clinical use. This drug helps people who are diagnosed with

• autorhymicity- The heart is autorhythmic. This means it generates its own rhythmic action potential independent of the nervous system.

reports the amount of force exerted by the blood into the arteries during ventricular contraction.