Anhydrobiois is the process through which some organisms remove their bulk water to inhibit freezing in colder temperature. Although extreme desiccation leads to dehydration, organisms can survive extreme conditions including starvation. Since there is no free water to support the diffusion of metabolic intermediates or the activity of enzymes, most anhydrobiotic organisms are ametabolic.
Extreme desiccation also places extreme stress on proteins and lipids due to the loss of hydration shells that are important for maintaining their functional conformation. Thus, these organisms use polyhydric alcohols including sorbitol and glycerol as cellular desiccants, to minimize “free water”, and stabilize proteins and membranes. Polyols form hydrogen
Levis, N. A., Yi, S. X., & Lee, R. E. (2012). Mild desiccation rapidly increases freeze tolerance of the goldenrod gall fly, eurosta solidaginis: evidence for drought-induced rapid cold-hardening. Manuscript submitted for publication, Available from Journal of Experimental Biology. (215, 3768-3773)Retrieved from http://jeb.biologists.org/content/215/21/3768.full
plasma membranes, meaning animals and plants contain lipids. In this paper I will display and
The protozoan commonly known as the “water bear” is an extremophile that has engaged many in the scientific community. The Tardigrade is an invertebrate that has eight legs and comes in many shapes and sizes. This group has many adaptations such as cryptobiosis that allows it to survive in extreme environments. The Tardigrade can be found from land, to water, to sulfur springs, and to over 25 species found in the frozen tundra of Antarctica (Miller et al, 2001). To understand these creatures this paper will summarize the taxonomy, reproduction, food, and protective genetics, of the Tardigrades. The first section to this paper will examine is how these creatures are divided taxonomically.
Dehydration can happen at any age and from a variety of primary causes including diarrhea, vomiting, use of diuretics, exercise, and exposure to extreme heat. The body has compensatory mechanisms to balance mild dehydration or fluid deficit of 2-4%; however, moderate fluid deficit of 5-8% can lead to electrolyte imbalances, postural hypotension, and dryness in skin and mucous membranes (Porth, 2011). In severe dehydration, or fluid deficits greater than 8% severe hypotension and shock can occur (Porth, 2011). The circulatory system has its own compensatory mechanisms for fluid volume deficits. These include changes in cardiac output, heart rate, and blood pressure.
Molin, M., Yang, J., Hanzen, S., Toledano, M., Labarre, J. and Nystrom, T. (2011). Life span extension and H2O2 resistance elicited by caloric restriction require the peroxiredoxin Tsa1 in Saccharomyces cerevisiae. Mol Cell, 43 (5): 823-833. doi:10.1016/j.molcel.2011.07.027.
Being hypothermic or having frostbite on any part of your body can be very dangerous. This is an interesting topic because it can happen to anyone at anytime and if your are not prepared for it, it can be life threatening. If you are just going out to play in the snow and you are not dressed warm enough or all your skin is not covered frostbite can develop and you are at risk of hypothermia. Even if it is not snowing and there is not a cloud in the sky you can develop hypothermia if it is cold enough. If you are going to go hiking or skiing you will want to be aware of what hypothermia is and what to do if you get frostbite as this can result in the amputation of limbs and fingers. When skiing up in Vermont over Christmas break while going down the mountain my fingers started hurting and they were very cold. My dad and I were going down to the base of mountain, it was our final run of the day. We were skiing in negative 20 degree weather. This sparked my interest in hypothermia and frostbite because if we had not decided to get off the mountain frostbite developed on my hands and fingers and I would have run the risk of maybe getting them amputated. The purpose of writing this paper is to show how dangerous and lethal hypothermia and frostbite are if not taken care of properly.
The hypothesis for this experiment was, If three different types of waters (saltwater, fresh water, tap water) are tested, then the liquids won’t evaporate at the same rate and tap water will evaporate at the fastest rate because it won’t have any non-volatile substances to hold it back from evaporating.
up of a glycerol (a type of alcohol with a hydroxyl group on each of
The Biological Importance of Water as a Solvent and as a Medium for Living Organisms
“Drinking water is like washing out your insides. The water will cleanse the system, fill you up, decrease your caloric load and improve the function of all your tissues.” – Kevin R. Stone --
Actually the nature of body, itself indicate the dehydration condition by regulate self mechanism. The thirst is body’s ways of telling that it needs the fluid. The thirst is the craving for fluids which is the sign of dehydration, resulting in the basic instinct of animals to drink. It is a mechanism involved for regulation of body in water balance. It arises when the water volume of the body falls below a certain threshold level. Because of that osmolite concentration becomes too high and the message go to the nervous system which cause the thirst is triggered. When the 2% body is hydrated that time thirst occurs and the mouth become dry. But in view of the fact that severe dehydration also not affect on the body but also mild dehydration also serious causes on the body. As thirst sense more slowly, it is difficult to understand the dehydrated situation. Furthermore sensation of thirst is gradually decreasing as raise the dehydration situation. This mild dehydration too effect on body by decreasing performance, energy level, consciousness, person’s mood. One of the lead scientists ...
Humans use water on a daily basis, in everything from drinking, to cleaning, and for recreational uses in pools or waterparks. But the human body itself is the main contester in how it is used. Water is a dissolving essential in vitamins and nutrients for food and for delivering them to cells. Our bodies also use water to flush out toxins, regulate body temperature, and aid our metabolism. The human body is 50-75 percent water, and when that water is lost in digestion or sweat, it needs to be replenished to continue functioning.
Everything from the hormonal activities in animals and plants, to kidney dialysis machines which are used to selectively remove water and some salts and wastes from the kidneys of ill people are all possible by the actions of osmosis and diffusion (Reasoner 1). However, perhaps one of my favourite applications of osmosis is in the use of food preservation. Because fruits contain such a high percentage of water (they almost universally have water contents that are greater than 75% of their weight), they spoil relatively easily and quickly (RRTCAD). Historically, human beings have gotten around this issue by drying their fruit through intense heating, boiling or exposure to the sun. However, this method of desiccation may take away some of the more favourable qualities of fruit and has been shown not to preserve fruits as well as a process called osmotic dehydration. Osmotic dehydration is a less harsh method of drying that mimics nature. First fruits are dropped in scalding water (i.e.
The process of alcoholic fermentation begins with the use of enzymes. The enzymes begin to break down the long chains in starch molecules, a polysaccharide that consists of a large quantity of glucose molecules (C6H12O6) joined by glycosidic bonds as seen in figure 1, into single glucose molecules, a monosaccharide with six carbons and five hydroxyl groups. After the starch has become sugar, the enzymes are used once again, this time to convert the sugars into ethyl alcohol and carbon dioxide, CO2, as seen in figure 2 (World of Scientific Discovery, 2007). The carbon dioxide produced is released into the atmosphere, leaving water and ethanol, the alcohol, behind. Ethanol is a colorless flammable liquid with a molecular formula of C2H6O, giving it a molar mass of 46.07 grams per mole. Ethanol is also characterized by a melting point of -114°C or 159 K.
When plants such as seaweeds or others that grow under water, their parts are supported on all sides by hydrostatic pressure. There is not much difference in the density between plant cells and their surrounding liquid environment. Aquatic plants do not require significant structural support; their cell walls only contain polysaccharides, c...