Daphnia or daphnids are commonly called water fleas because of their jerky or jumping swimming style. Daphnia is a genus of small, aquatic (mostly freshwater), generally between .2 and 5 mm in length, and characterized by a single compound eye, two double branched antennae, and generally have a translucent exterior. Daphnia is planktonic crustaceans that belong to the class of Branchiopoda, which are characterized by flattened leaf-like legs used to produce a water current for the filtering apparatus. Within the branchiopods, Daphnia belongs to the order of Cladocera, whose bodies are enclosed by a translucent shell, known as the carapace. It has a double wall, between which hemolymph flows and which is part of the body cavity. The carapace …show more content…
For humans, daphnia also makes model organisms for biological study. The translucent carapace makes them excellent subjects for the microscope as one can observe the beating heart (John Clare, …show more content…
In a closed system, blood is always contained within vessels (arteries, veins, capillaries, or the heart itself. In an open system, blood (usually called hemolymph) spends much of its time flowing freely within body cavities where it makes direct contact with all internal tissues and organs. In humans, the heart is the main pump which divided into four chambers. The top two chambers are the atriums and the bottom two chambers are the ventricles. Blood enters the heart through the superior and the inferior vena cava. These are the two largest veins in the body. Unlike humans, fishes exhibit single cycle circulation, where the oxygen deprived blood comes to the heart, from where it is pumped to the gills and then circulated to the entire body (BBC, 2014). Daphnia depends on oxygen levels in the environment, moreover, they adapt to the changing levels of oxygen in the atmosphere. When there is a scarcity of oxygen, they produce hemoglobin, an oxygen transport molecule. The normal oxygen level daphnia lack hemoglobin, however, the low-oxygen level daphnia are protein rich and turn bright red which eases the effort of the hungry fish in spotting them (Bergen, 2004). This experiment is to test the effect of 10% alcohol in Daphnia’s heart rate. Daphnia, like many animals, is prone to alcohol intoxication
Planaria usually live in water, water doesn’t have any effect on them which the reason why it is used as a control group in this experiment. Planarian will be put near the edge in a two-chamber tray containing water, in the side that is not covered with a dark piece of paper. Five planaria will be tested in a 2- chamber tray. We will measure how long it takes the planaria to move from the edge of a chamber receiving light, to the dark chamber. Subsequently, start by adding the lower concentration of caffeine in the water, replacing planarian in the same position and measuring how long it takes now to go back to the dark chamber in the presence of caffeine. We will duplicate the same procedure with higher concentrations of caffeine and additionally take the average of the time all five planaria took to move from the edge of the chamber in brightness, to the dark chamber in different concentrations of
The experiment studies the effects of Red Bull and its major components on the heart rate of a Daphnia. The experiment focuses on the effects of conditions on the cardiovascular system. The Cardiovascular system is responsible for the transport of blood, oxygen, nutrients and waste circulating the body. It consists of the heart, vessels, and blood as in closed circulatory system and hemolymph in open circulatory system, the cardiovascular system is also responsible for thermoregulation in the body. (Gonzalez, 2012). The heart helps pump blood to the lungs and rest of the body. The pumping of heart or the contraction and relaxation of heart determines the heart rate and depends on multiple chemicals that we could influence by using stimulants, depressants, varying temperatures, aerobic, and anaerobic
· The daphnia will be submersed in the water and left to equilibrate for 3 minutes, after this time one of the Daphnia will be removed and put onto a microscope slide, this will then be quickly put under the microscope. -1- · Under the microscope, the Daphnia will be observed for 20 seconds, this heart rate will be counted and recorded, this can the be
I predicted that the blackworms in higher caffeinated solutions would have higher pulse rates, because caffeine is known to increase blood pressure and heart rate. However as far as scientists know, invertebrates are not expected to have a strong response to caffeine like vertebrates do. Also, caffeine in low doses is known to lower pulse rate. The results do not support my hypothesis. The results show that when black worms are placed in caffeinated solutions, their pulse rates on average are lower than those placed in a solution with no caffeine. A possible flaw that may have occurred during experimentation is that the petri dishes were not properly cleansed, or that there were other properties in the water that influenced the outcome. To eliminate these flaws, I could have boiled the petri dishes and water to insure that there were no other properties to influence the data. Further experimentation should be performed with higher doses of caffeine to further insure that caffeine does in fact lower their pulse rate. The insufficient number of trials performed lead to less confidence in my conclusion that caffeine lowers the heart rate in
The second part of this lab was a computer simulation program to illustrate a frog’s electrocardiogram using various drugs in an isolated setting. The computer program entitled “Effects of Drugs on the Frog Heart” allowed experimental conditions to be set for specific drugs. The different drugs used were calcium, digitalis, pilocarpine, atropine, potassium, epinephrine, caffeine, and nicotine. Each of these drugs caused a different electrocardiogram and beats per minute reading. The calcium-magnesium ration affects “the permeability of the cell membrane”(Fox). When calcium is placed directly on the heart it results in three physiological functions. The force of the heart increases while the cardiac rate decreases. It also causes the appearance of “ectopic pacemakers in the ventricles, producing abnormal rhythms” (Fox). Digitalis’ affect on the heart is very similar to that of calcium. It inhibits the sodium-potassium pump activated by ATP that promotes the uptake of extracellular calcium by the heart. This in return strengthens myocardial contraction (Springhouse). Pilocarpine on the other hand
Daphnis et Chloé begins in a meadow outside a sacred wood, where there is a statue of three Nymphs and a statue of the god Pan. Youths and maidens enter carrying open baskets of gifts intended for the Nymphs. The stage gradually fills. The crowd bows before the altar of the Nymphs. The maidens wrap garlands around the pedestals. Daphnis et Chloé begins with a religious dance. Daphnis enters, preceded by his flocks, and Chloé join him. They bow down before the nymphs and interrupt the dances. The maidens enter and flirt with Daphnis, which upsets her. She is drawn into a dance with you men, when another herdsman named Dorcon pursues her aggressively, which upsets Daphnis. They proceed to the general dance, which includes everyone. Dorcon wants
Viperfish has its own scientific name, Chauliodus Sloani. It lives in the darkest depth of the sea in the range between 250 to 5000 feet in the daytime and shallower depths at night, primarily in tropical and temperate waters. Viperfish only grows up to 60 centimetres . However, they possess extremely over-grown teeth which is very useful for hunting prey. This fierce creature has developed a specialize hunting technique that is perfect for deep ocean floor where there is no light. This fish generates its own light and uses it to attract prey through a process known as bioluminescence . Viperfish has several light-generating-organs along the side of its body called the photophores. They also have a long spine in their back with another photophores at the end of it. They mainly use the photophores to communicate with other members of the species such as when they are attracting mate .
Elaborate: The cardiac cycle of the heart is divided into diastole and systole stages. Diastole refers to the period of relaxation experienced by the atria and ventricles. Systole is the contraction of the atria and ventricles. The pattern of blood flow starts in the left atrium to right atrium then into the left ventricle and right ventricle. During its course, blood flows through the mitral and tricuspid valves. Simultaneously, the right atrium is granted blood from the veins through the superior and inferior vena cava. The job of the superior vena cava is to transport de-oxygenated blood to
As blood travels through the circulatory system, it is first pumped from the right side of the heart to the lungs through the pulmonary arteries and then separates into arterioles which split into capillaries. Here, the deoxygenated blood receives oxygen diffused in the lungs due to large surface area and travel back through venules and then pulmonary veins to the left side of the heart. From here, the oxygen rich blood is pumped throughout the body in arteries, arterioles, and capillaries, providing the body and cells with nutrients through osmosis. Afterwards, the now deoxygenated blood travels back to the right side of the heart containing deoxygenated blood, through venules and vein to repeat the cycle over again. Also, the heart is nourished by coronary circulation through the Right and Left Main Coronary Arteries.
oxygen to survive. If the oxygen level is depressed to zero, all fish in the
In Labs 22 through 26, my lab partner and I were assigned a fetal pig to perform a dissection on in order to understand anatomy, the study of an organism’s structure1, and physiology, the study of the functions and activities of a living organism2. Throughout these labs, we studied the structure of the fetal pig and performed experiments to understand four system processes: digestion, cardiovascular, respiratory, and excretory. Dissecting an organism, physically moving and seeing the different portions of the organism, especially of a fetal pig, is very important. This helps in the understanding of the skeletal structure and what series of physical and chemical processes the mammalian species body performs in order to survive.
It was placed on a slide, a couple drops of water was placed on the slide to keep it moisturized. Next, we used a microscope to observe the heart beating in the transparent animal. According to the lab report on page 98 the normal heartbeats are about 350 per minute. By using a pencil and paper, we made a small dash for every heartbeat over a 15 second interval. Than we continued to repeat the observation of the heartbeats 3 more times for a total of 4 observations. We than totaled up the number of dashes and calculated the average of the four 15 second observations, this was labeled “Normal Heart Rate” on Table 1. Next we added 1 drop of an “unknown” solution that was assigned, we made sure to determine the average normal heart rate before doing do. The same procedure outlined above was conducted. The records were than placed in table 1. We than used water in replace of the unknown solution. The same procedure was conducted, we analyzed whether the Daphnia had recovered or not. Lastly our records were compared among our
Crustacea is a large subphylum of Arthropoda, consisting of almost 52 000 described species, including animals like crabs, lobsters, shrimp and barnacles. The majority of these are aquatic, living in marine or fresh water environments, though some have adapted to living on land like some crabs and woodlice. Most crustaceans are relatively small, though there are some exceptions. All of them have a hard, strong exoskeleton, divided into two parts, which has to be shed in order to allow the animal itself to grow. They have a large circulation system, where blood is pumped around the body by the heart. Only some crustaceans have sexes separate, and those that are usually mate seasonally and lay eggs. The study of Crustacea is called carcinology.
...n in Starfish Caught by Towed Demersal Fishing Gears." Marine Biology 138.3 (2001): 527-36. Print.