Lab Report Comparing Oxygen Consumption Rates in Different Mammalian Subclasses
The purpose in experimenting with computer simulations was to compare oxygen consumption rates in different mammalian subclasses. We compared monotremes, marsupials, and placental mammals at both warm and cold temperatures. The results supported our hypothesis that when temperature increased, metabolic rate decreased. This was also supported using a student's t-test. We also found that placental mammals had the highest oxygen consumption rates and marsupials had the lowest. We compared oxygen consumption rates in different sized crabs at different temperatures. The results supported our hypothesis that the smaller crab would have a higher rate of consumption. However, in the crabs, as temperature was increased, metabolic rate increased also.
Introduction
The second law of thermodynamics affirms that all living organisms must receive a constant energy input in order to survive (Witz 2000). Almost all bodily activities require energy. It is important to study how animals obtain, process, and dispose of products needed to maintain a positive energy balance. When cellular respiration occurs in the body, heat is produced and given off into the environment by the release of potential energy contained in the chemical bonds of macronutrients. The amount of heat released into the environment and the rate at which chemical reactions occur in the cells are directly related. Two different relationships exist, one that describes the endothermic animal and one that describes the endothermic animal. The rate of heat produced by the endothermic animal while at rest, fasting, and within the thermoneutral zone is dependent upon the basal metabolic rate (BMR). The thermoneutral zone of the endotherm is described as the range of ambient temperatures within which there is a limited change in metabolic rate. The standard metabolic rate is what the rate of heat loss in ectotherms relies upon. The difference between the two rates is the temperature factor. Due to that fact that the temperature of ectotherms has a wider range with ambient temperature than the endotherms, physiologists defined a different measure for the basal level of metabolism.
Although it is possible to measure the animal's heat lost to the environment by direct calorimetry, it is easier to use indirect calorimetry. An effective way of measuring heat loss is to use the rate of oxygen consumption. Since oxygen is required by most animal cells using biochemical pathways to metabolize macronutrients, and it varies in a predictable way, it is useful in determining metabolic rate.
The various modes of heat loss during this phase include radiation, convection, conduction and evaporation. Radiation contributes to maximum heat loss (approximately 40%) and is determined by the fourth power of difference between ambient and core temperature. Convection is the next most important mode of heat loss (upto 30%), and is due to loss of heat to air immediately surrounding the body. It is proportional to the square root of the velocity of the air currents. Evaporation contributes to less than 10% of heat loss and occurs from cleaning fluids as well as skin, respiratory, bowel and wound surfaces. Conduction accounts for least heat loss (upto 5%) and is due to cold surfaces in contact with the body such as operating room table. After 3-4 hours, a plateau phase is realized when core heat production equals heat loss to the periphery and core temperature reaches a
The respiratory system is responsible in regulating gas exchange between the body and the external environment. Differences in respiration rate indirectly influence basal metabolic rate (BMR) by providing the necessary components for adenosine triphosphate (ATP) formation (Williams et al., 2011). Observation of gas exchange were measured and recorded for two mice (mus musculus) weighing 25 g and 27 g under the conditions of room temperature, cold temperature (8°C), and room temperature after fasting using a volumeter. The rates of oxygen consumption and carbon dioxide production were measured and used to calculate BMR, respiratory quotient (RQ) and oxidation rate. The mouse at room temperature was calculated to have a BMR of 2361.6 mm3/g/hr. Under conditions of cold temperature and fasting, the BMR values decreased to 2246.4 mm3/g/hr and 2053.2 mm3/g/hr respectively. Rates of glucose oxidation increased under these treatments while rates of fat oxidation decreased. Respiratory quotient (RQ) values were calculated to determine the fuel source for metabolic activity. On a relative scale, protein or fat appeared to be the primary fuel source for all three treatments although the mouse at 8°C had the highest RQ and may have relatively used the most glucose. It was also concluded that BMR in mice are greater than in humans.
Metabolic rate is directly linked to the core temperature in an animal. An ectotherm, or cold blooded animal, warms its body mainly by absorbing heat from its surroundings. The amount of heat it derives from its metabolism is negligible. In contrast, endotherms derive most or all of its body heat from its own metabolism (Campbells,p899). Because ectotherms do not produce their own heat, they cannot actively ensure their ideal temperature for an ideal metabolic rate (aquacult.htp).
The Effect of Temperature on an Enzyme's Ability to Break Down Fat Aim: To investigate the effect of temperature on an enzyme’s (lipase) ability to break down fat. Hypothesis: The graph below shows the rate increasing as the enzymes get closer to their optimum temperature (around 35 degrees Celsius) from room temperature. The enzyme particles are moving quicker because the temperature increases so more collisions and reactions occur between the enzymes and the substrate molecules. After this the graph shows the rate decreasing as the enzymes are past their optimum temperature (higher than). They are getting exposed to temperatures that are too hot and so the proteins are being destroyed.
Mader, S. S. (2010). Metabolism: Energy and Enzymes. In K. G. Lyle-Ippolito, & A. T. Storfer (Ed.), Inquiry into life (13th ed., pp. 105-107). Princeton, N.J: McGraw Hill.
Works Cited "Animal Planet" Animal Planet. N.p., n.d. Web. The Web. The Web. 09 Apr. 2014. The 'Standard' of the 'Standard'.
Ross, A. C. (2005). Physiology. In B. Caballero, L. Allen, & A. Prentice (Eds.), Encyclopedia of
Hummingbirds have evolved certain behavioural and physical traits which allows for them to be more energetically efficient, such as specialized storage and digestion adaptations, feeding and flying adaptations and breathing adaptation. Hummingbirds are extremely small and their muscles for flight are highly oxygen-dependent and require large amounts of energy. Hummingbirds are one of the smallest endotherms and any energetic output can be metabolically stressful. The hummingbirds’ small body size means that they have very little room for energy storage and therefore often endure energetic and metabolic stresses. They are the one of the oldest aves, dating back to some 33 million years ago and have evolved certain energy efficient adaptations that have allowed for them to live so long. These adaptations allow Hummingbirds to efficiently meet their energetic needs which in turn, allows for them to not only survive but also continue to evolve and expand their specific niches.
The debate of whether dinosaurs were cold blooded or warm blooded has been ongoing since the beginning of the century. At the turn of the century scientists believed that dinosaurs had long limbs and were fairly slim, supporting the idea of a cold blooded reptile. Recently, however, the bone structure, number or predators to prey, and limb position have suggested a warm blooded species. In addition, the recent discovery of a fossilized dinosaur heart has supported the idea that dinosaurs were a warm blooded species. In this essay, I am going to give supporting evidence of dinosaurs being both warm and cold blooded. I will provide background information on the dinosaur that was discovered and what information it provides scientists.
In an article titled “Energy Digestibility of Giant Pandas on Bamboo-Only and on Supplemented Diets”, the goal of this study was to figure out the energy digestibility of bamboo by giant pandas using digestibility trials and through analysis using bomb calorimetry. An energy budget is a numerical statement that measures the amount of energy collected and the placement of the energy to various functions. Energy budgets can be described using the equation: E=M+P+U+F (where E is the total amount of energy consumed, M is the energy used for maintenance and activity, P is the energy used for production (which includes growth and reproduction), U is the energy lost in urine, and F is the energy lost in feces.). The total energy consumed minus the energy lost in feces is the digestible energy and shows the ability of the digestive system to process consumed food.
In 2002, a group of Australian researchers published a paper entitled the "Effect of different protocols of caffeine intake on metabolism and endurance performance". Caffeine use during sporting events has become much more popular and has widely studied. The purpose of the research was to examine the work increasing (ergogenic) effects of differing regiments of caffeine on metabolism and performance while simulating the typical nutritional preparation an athlete would do for a race. The study also sought to examine the effect of timing of caffeine intake, comparing results when caffeine was given before an event (precaf) to results from caffeine given during an event (durcaf). In addition, the researchers wanted to understand the practice of endurance athletes drinking defizzed Coca-Cola towards the end of a race. It was widely observed that many triathletes and marathoners feel they derive a boost from consuming Coca-Cola in the final stages of an event as a replacement to sports drinks.
Our metabolism, “the totality of an organism’s chemical reactions”, manages energy usage and production of cells. We use energy constantly and our metabolism breaks down food through complex chemical reactions into energy our cells
Now I am going to explain the physiology of the cardiovascular system and the respiratory system in relation to energy metabolism in the body.
“Animals were used in early studies to discover how blood circulates through the body, the effect of anesthesia, and the relationship between bacteria and disease” (AMA 59). Experiments such as these seem to be outdated and actually are by today’s means, scientists now commonly study for three general purposes: (1) biomedical and behavioral research, (2) education, (3) drug and product testing (AMA 60). These three types of experiments allow scientists to gain vast amounts of knowledge about human beings.... ... middle of paper ... ...& Co.
From my reading I learned that cellular respiration is a multi-step metabolic reaction type process that takes place in each living organism 's cell rather it be plant or animal. It’s my understanding that there are two types of cellular respiration, one called aerobic cellular respiration which required oxygen and anaerobic cellular respiration that does not require oxygen. In the anaerobic cellular respiration process, unlike the aerobic process oxygen is not required nor is it the last electron acceptor there by producing fewer ATP molecules and releasing byproducts of alcohol or lactic acid. The anaerobic cellular respiration process starts out exactly the same as anaerobic respiration, but stops part way through due to oxygen not being