In the early development process of many organisms, it is important to be able to minimize exposure to agents of stunted or arrested development. By decreasing the mortality rate for a generation of a species, that species is given an advantage in later reproduction; by increasing the number of organisms of the same species within a limited environment, more organisms of the same species are able to reproduce, resulting in an augmented overall population ("Reproduction and Development", 2013). However, when toxins are introduced to an environment, an embryo’s viability can decrease. Mortality rates for the generation of the species can increase, and defects that are harmful to the reproductive cycle can emerge. Thus, it is necessary to measure and observe the effects of certain toxins on embryonic development. The North American brine shrimp, or Artemia Franciscana (Artemia Salina), is subject to changes in its environment. Toxins introduced to its hatching environment, such as ethanol (in concentrations of 0.1%, 0.15%, and 0.2%), can have significant impact for the hatching process and embryonic development. The experiment sought to explore the relationship between birth defects and exposure to ethanol at early developmental stages through the use of American brine shrimp. However, to be able to fully comprehend the impact that certain toxins would have on the embryonic development of the North American brine shrimp, it is first important to be versed in its specific hatching process.
The North American brine shrimp goes through several stages in development before reaching adulthood. The brine shrimp is first encased in a protective capsule within a female brine shrimp’s brood sac (Drewes, C, 2006). Here, egg development rapidly...
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... ethanol present. Due to the fact that there has been a distinct correlation between the levels of ethanol present and the mortality rate of certain aquatic life forms, it was expected that when a higher concentration of ethanol was present in the artificially constructed environment, the brine shrimp would have a lower rate of hatching and a higher mortality rate. It was anticipated that if the brine shrimp cysts were exposed to levels of ethanol in 0%, 0.1%, 0.15%, and 0.2%, than the brine shrimp cysts exposed to higher levels of ethanol would develop more slowly due to the fact that ethanol changes the shape of proteins when it permeates the membrane of a call. Thus, the brine shrimp’s exposure to 0.2% ethanol would yield higher mortality rates and more developmental problems than when the brine shrimp were exposed to 0.15% ethanol, 0.1% ethanol, and 0% ethanol.
The Artemia franciscana can survive in extreme conditions of salinity, water depth, and temperature (Biology 108 laboratory manual, 2010), but do A. franciscana prefer these conditions or do they simply cope with their surroundings? This experiment explored the extent of the A. franciscanas preference towards three major stimuli: light, temperature, and acidity. A. franciscana are able to endure extreme temperature ranges from 6 ̊ C to 40 ̊ C, however since their optimal temperature for breeding is about room temperature it can be inferred that the A. franciscana will prefer this over other temperatures (Al Dhaheri and Drew, 2003). This is much the same in regards to acidity as Artemia franciscana, in general thrive in saline lakes, can survive pH ranges between 7 and 10 with 8 being ideal for cysts(eggs) to hatch (Al Dhaheri and Drew, 2003). Based on this fact alone the tested A. franciscana should show preference to higher pH levels. In nature A. franciscana feed by scraping food, such as algae, of rocks and can be classified as a bottom feeder; with this said, A. franciscana are usually located in shallow waters. In respect to the preference of light intensity, A. franciscana can be hypothesized to respond to light erratically (Fox, 2001; Al Dhaheri and Drew, 2003). Using these predictions, and the results of the experimentation on the A. franciscana and stimuli, we will be able to determine their preference towards light, temperature, and pH.
A lobster must shed its shell in order to grow. It takes about five to seven years for a lobster to become a legal size harvestable adult. Soft-shell is the term used for a newly molted lobster. A soft-shell lobster has a shell with room for growth. Soft-shell lobsters are not as full of meat because their new shell is larger than the muscle inside the body. The part not filled with its body’s muscle tissue is filled with water. Soft-shell lobsters may look big on the outside, but they have a much lower meat yield on the inside. Most adult lobsters molt from June to September depending upon location and water temperatures.
To begin the lab, the variable treatment was prepared as the Loggerlite probe, used to later measure oxygen consumption, warmed up for approximately 10 minutes. To prepare the variable treatment, 200ml of Sodium and Ammo-lock water was measured in a container and a pre-prepared “tea bag” of tobacco was steeped in the room temperature treated water until a light yellow color was visible. After preparing the tobacco solution the preparation for the live goldfish began as two beakers were filled with 100 ml of treated water. Each beaker was weighed before addi...
The crustacean moult cycle is initiated when the Y-organ in the head secretes the hormone Ecdysone (E) into the circulatory system[3,4,5]; the Y-organ is the primary source of E[5]. Upon contact with the haemolymph (a combination of blood and tissue fluid) within the circulatory system E is converted to its active form, 20-hydroxyecdysone (20E), by a P450 enzyme[4]. This causes the epidermal cells to secrete moulting fluid, which contains a mixture of enzymes such as proteases and chitinases. The moulting fluid degrades the exo- and endocuticle, and the digested cuticle is reabsorbed to create new cuticle; moult fluid also has a role in initiating the moult. The degraded cuticle is replaced by water or air so that the animal can swell in order to lose the shell. During the passive phase of the moult cycle, the shell splits along the break point caused by the decalcification of the shell, in the crab this is along the epimeral lines. Once the shell has split, the animal wiggles side-to-side to free itself from i...
The purpose of this lab was to study the response of the genus Daphnia to chemical stimuli and to examine human responses to different stimuli. A stimulus is an incentive; it is the cause of a physical response. Stimuli can have a physical or chemical change; an example of a physical change is a change in temperature and sound. An example of chemical change would be changes in hormone levels and pH levels. Muscular activity or glandular secretions are responses that occurs when stimulus information effects the nervous and/or hormone system. Daphnia is a genus; it is a small crustacean that lives in fresh water. The body of the daphnia is visible and its internal organs are clearly seen thus it was chosen for this exercise. The
The understanding of Saballaria cementarium's diet has not been thoroughly examined in much detail. Qian and Chia (1990) examined the role of detritus, form of eelgrass, as a food source for developing larvae of the organism. It is not known whether they are food limited. The experiment was conducted to reveal some facts about the feeding habits of the larvae in determining the development and growth of it. The invertebrate larvae's primary food source comes from the phytoplankton that is found in abundance at the bottom of the sea floor. The larvae fed with detritus were compared with those fed on equal concentrations of phytoplankton. Other tests were conducted to compare the degrees of survivorship among the larvae using varying concentrations of phytoplankton. Higher concentrations of phytoplankton, consumed by the larvae, yielded
The experiment measured the survival rate, the growth rate, and the size of the brine shrimp at the time harvested in various environments. To obtain these measurements, three environments were created: sea water, brackish water, and freshwater. For this experiment the scientists used 5 liter plastic buckets. Every two days, half of the water from each bucket was discarded and new water, of each respective salinity, was added into each bucket...
For many years it was believed that alcohol can affect an unborn child only after placenta and umbilical cord are fully developed. Ten to fourteen days after fertilization the egg arrives into the uterus, and nests there. In that phase there is no connection between a mother’s bloodstream and a child via umbilical cord, but while placenta is developing embryo is getting its nutrients from mother’s blood through yolk sac. The minute alcohol enters mother’s bloodstream trough her stomach and the small intestine, it will also get to the embryo by cellular processes and it will disturb the cell division.
While brine shrimp seem to be good indicator species due to the fact that they are all very genetically similar, they are not. The brine shrimp react are too sensitive towards the rubbing alcohol then humans would be. Due to their size and the way they in take the toxins, by being soaked in it, is very different from the way humans intake it, which causes them to be bad indicator
Many studies have established that a developing organism is susceptible to exogenous and endogenous factors during certain stage of the organism’s development. The effects of ethyl alcohol or ethanol on the developing fetus, which manifest a variety of characteristic abnormalities, are collectively called Fetal alcohol Syndrome. Ethanol exposure to the fetus causes various malformation ranging from the cellular to the organismic levels with the eventual results frequently being different levels of mental retardation (3).
Alcohol is an ethanol containing substance that is a common beverage in many social and private settings. Alcohol is also a teratogen, therefore alcohol co...
...oney, Andrew A. and Daniel B. Pickford. 1995. Organisation versus Activation: The role of Endocrine-disrupting Contaminants (EDCS) during Embryonic Development in wildlife. Environmental Health Perspective’s. 103 (Suppl 7): 157-164.
Applying Alcohol Myopia to Animal Experimentation.” Oxford Journals 40.5 (2005): 373-378. Web. 6 Nov. 2011.
There have been many experiments over the past few decades testing for prenatal alcohol exposure. These studies have shown that exposure causes a variety of abnormalities. These abnormalities include unusual growth, mental disabilities, Central Nervous System deformities, and distinct craniofacial disfiguration (Ungerer, Knezovich and Ramsay, 2013).
Nelson, A.N. 1971. Effects of oil on marine plants and animals. London: Institute of Petroleum.