Temperature regulation practical - Homeostasis.
TEMPERATURE REGULATION PRACTICAL - HOMEOSTASIS Planning A Introduction 'Homeostasis' means 'to maintain the balance' within the body, of the internal environment. The 'internal environment' is the tissue fluid that bathes the cells. This fluid provides oxygen, nutrients, and removes wastes from cells. The conditions of the internal environment which must be maintained within narrow limits are blood pH, oxygen and carbon dioxide concentrations, blood glucose concentration, salt content of blood, water balance and temperature. The two systems involved in homeostasis are the endocrine system and nervous system. The brain monitors the temperature of the blood and compares it with a set point, usually close to 37°C. If the blood is lower or higher than the set point, the brain sends messages to parts of the body to make them respond and bring the temperature back to the set point. This is an example of negative feedback. A negative feedback system means that a change of an internal factor causes effectors to restore the internal environment to its original level. It is named so because the response to the change has the opposite effect of the stimulus. During exercise, the rate of aerobic respiration is muscle rises so that there is an increase in the CO2 concentration of the blood. This reduces the pH of the blood and is detected by chemosensors in the walls
Homeostasis and excretion.
Homeostasis and excretion. Homeostasis: mechanism that maintains the internal environment at a constant level. This including the blood pH, the O2 and CO2 levels, blood glucose level, blood temperature and the water balance. This is all controlled by a negative feedback system; in this the product controls its own production. This system has three parts to it: . Sense organ that senses the difference, 2. Control centre generates a message for 3 to act, 3. Response organ this brings on the change, after receiving the message. Due to these parts, homeostasis needs the CNS and the endocrine systems to help it control it all. Thermo-regulation: Thermo-receptors in the skin monitor the skin temperature. For the body the main source of heat is the liver and muscle movement, thus shivering when cold, to enhance muscle movement to obtain some sort of heat. Regulation: is through: . Sweating when water on the skin evaporates it has a cooling effect 2. Radiation of heat the heat is radiated into the air or is conducted (transferred) to any object touching the body. This is done through blood vessels under the skin that either dilate when the body is hot or constrict when the body is cold. Body warm = vasodilatation, body cold = vasoconstriction. 3. Convection heat lost due to normal air circulation: wind=cold. The skin has hairs on it that are controlled by hair erector
Homeostasis Is a Central Theme In Animal Physiology.
Homeostasis Is a Central Theme In, Animal Physiology Homeostasis is the name given to the process that allows optimum conditions to be regulated in the body. This regulation of the internal environment must be independent of external environmental constraints. In humans this process is controlled by almost all of the bodily systems but mainly by the endocrine, respiratory and renal systems. Homeostasis therefore allows an organism to live in habitats that are not ideally suited to the internal environment, because, only in favourable conditions will the organism thrive. This allows the organism to in an environment not best suited to it's internal functioning but in conditions which may be favourable for foraging etc. a prime example are fish, a fresh water fish lives in an environment which in definition is more dilute than within it's internal environment, sea water fish on the other hand live in a environment where its surroundings are more alkali than its internal environment. The need for homeostasis can be "traced" to the cellular level, as cells interact with their immediate environment (either via cellular communication, signal proteins, expulsion of ion, and uptake of ions). It is this communication, which ultimately leads to a change in the external environment. Right to the organ level or tissue organisation were for example the expulsion of urea changes the
The objective of this lab was to experiment with a negative feedback amplifier and predict its gain without the feedback.
20ECES465 Electronics Laboratory Section 001 1/04/03 Objective The objective of this lab was to experiment with a negative feedback amplifier and predict its gain without the feedback. Procedure After connecting the circuit per specifications in part one of the lab manual and verifying 7the voltage input and output we manipulated RFEEDBACK2 in order to achieve a gain of 100 v/v at a frequency of 1 KHz. We then made a screen dump of the Acircuit value. Since we were experimenting in the real world we could not use the ideal values for the components. Table 1 shows the ideal values called for in the lab report and the actual resistance values measured by a multimeter. Table 1: Resistance values Ideal (?) Real (?) 2.28k 2.26k 78.7k 78.6k .85k .85k 8.77k 8.8k 2.28k 2.29k 78.7k 78.7k 8.77k 8.74k .75k .750k We then swept the voltage in order to find the fH frequency. We then solved Equation 1 to get the feedback factor H. After we isolated H we could then predict what the gain of the circuit would be without the feedback factor. We then opened the circuit, which resulted in the RFEEDBACK2 value of infinity. The resulting circuit gave us an output of 15.09 V with an input of .01 V. This gave us a gain of 1509 V/V. We then swept the frequency to determine fH without the feedback. Then we calculated the gain-bandwidth product with and without
Regulation and Control Homeostasis.
Regulation and Control Homeostasis: Homeostasis is defined as the maintenance of a constant internal environment. This is very important for organisms because: * Chemical reactions can take place at predictable rates. * Mechanisms are more efficient as optimum conditions can be maintained for enzymes, etc. * Organisms can acquire a degree of independence from the environment. They need not be limited to one geological location where the conditions fit their needs, but can spread out. Their activity is also not restricted to a certain time, season, etc. Principles of Homeostasis: All homeostasis mechanisms follow approximately the same steps. Input Receptor Effector Negative Feedback Receptor: Signals the deviation of a quantity from the normal, set level. Effector: Brings about the necessary change needed to return the system to the reference point. Negative Feedback: This monitors and controls the extent of the correction. In other words, this makes sure that, as levels return to normal, the corrective mechanisms are scaled down (so that a shortage or excess of the substance does not occur) Homeostatic Functions of the Liver: Carbohydrate Metabolism * The livers major role in the metabolism of carbohydrates is to convert excess glucose absorbed from the intestines into glycogen. This is stored mostly in liver and muscle cells. * The stored glycogen can be
Revision questions on Communication, Homeostasis and Energy
F214-Communication, Homeostasis and Energy Module 1-Communication and Homeostasis 4.1.1 Communication a. Outline the need for communication systems within multicellular organisms * External environmental changes o Changes in the external environment can cause stress. o It may change slowly so there will be a gradual response. o It may be a quick change so a rapid response is needed. * Internal environmental changes o The environment of internal cells is that they are protected by epithelial cells and they are bathed in tissue fluid. o The activities of cells alter their environment e.g. releasing toxic products that need to be removed. * Coordination of activities of organs o Groups of specialised cells form tissues and organs. o Cells monitor the blood and can release a substance into the blood to remove certain substances. b. State that cells need to communicate with each other by a process known as cell signalling * Cells need to communicate to ensure that the different parts of the body work together effectively. * Cell signalling-The process where one cell releases a chemical that is detected by another cell which will react and respond to the signal. c. State that neuronal and hormone systems are examples of cell signalling * Neuronal systems o Interconnected network of neurones that signal to each other across synapse junctions. * Hormonal
What is Homeostasis?
Homeostasis is involved in keeping the body's internal environment constant (like the thermostat of a central heating system). Homeostasis keeps the body's temperature at a certain level (36.5oC) and it keeps the pH of the body at a certain level so that enzymes don't denature. Blood glucose is kept constant, CO2 levels and O2 levels are monitored to ensure that enough oxygen and not too much carbon dioxide are in the blood. The overall concentration and volume of blood is also monitored homeostatically. The term Homeostasis was first used by Cannon in the late 1920s. Homeostasis is very important to animals because it allows them to rely on the external environment. A constant internal environment allows a considerable degree of independence and allows animals to live in areas from the arctic to the tropics. Many of the mechanisms involved rely on negative feedback. A movement from the set level (e.g. a rise or fall in body temperature) is detected by receptors. These receptors then send information to the control centre in the brain which reacts by returning to the original value. For example, the temperature control mechanism. Humans maintain body temperature within 1oC of 36.5. If the temperature rises too high, the resulting increase in blood temperature is detected by receptors in the hypothalamus in the brain. The heat loss centre also in the hypothalamus sends
Describe the Concept and Discuss the Importance of Homeostasis
Describe the Concept and Discuss the Importance of Homeostasis Homeostasis occurs to some extent in all living organisms. All organisms need some control on their internal environmental conditions in order to ensure that they will be able to survive. Since many of the metabolic reactions that occur within an organism depend on the use of enzymes or even the use of other organisms such as prokaryotic bacteria, it is essential that the optimal conditions required for the functioning of that enzyme be provided. Homeostasis therefore, is 'the tendency of organisms to regulate and maintain relative internal stability', and involves, among other processes, the maintenance of a constant body temperature, glucose concentration, pH, osmotic pressure, oxygen level, and ion concentrations. The ability to maintain a constant internal environment, with which we are most familiar, is that of a constant body temperature in homeothermic organisms. For example, the average body temperature of a human is 36.6°C, and varies not more than 0.5 of a degree in healthy humans. However, Poikilotherms are animals whose body temperature fluctuates with the ambient temperature, and thus have no biochemical method of temperature maintenance. Since control is needed however, Poikilotherms, such as chameleons, have developed adaptive methods for coping with this problem. They often bask in the sun
Whats involved in Homeostasis.
Homeostasis Homeostasis is involved in keeping the body's internal environment constant (like the thermostat of a central heating system). Homeostasis keeps the body's temperature at a certain level (36.5oC) and it keeps the pH of the body at a certain level so that enzymes don't denature. Blood glucose is kept constant, CO2 levels and O2 levels are monitored to ensure that enough oxygen and not too much carbon dioxide are in the blood. The overall concentration and volume of blood is also monitored homeostatically. Cannon first used the term Homeostasis in the late 1920s. Homeostasis is very important to animals because it allows them to rely on the external environment. A constant internal environment allows a considerable degree of independence and allows animals to live in areas from the arctic to the tropics. Many of the mechanisms involved rely on negative feedback. A movement from the set level (e.g. a rise or fall in body temperature) is detected by receptors. These receptors then send information to the control centre in the brain which reacts by returning to the original value. For example, the temperature control mechanism. Humans maintain body temperature within 1oC of 36.5. If the temperature rises too high, the resulting increase in blood temperature is detected by receptors in the hypothalamus in the brain. The heat loss centre also in the hypothalamus sends
With reference to specific examples and mechanisms assess the significance of homeostasis to the human body.
WITH REFERENCE TO SPECIFIC EXAMPLES AND MECHANISMS ASSESS THE SIGNIFICANCE OF HOMEOSTASIS TO THE HUMAN BODY What is homeostasis? According to the 'Oxford Colour Medical Dictionary, Third Edition' homeostasis is the "the physiological process by which the internal systems of the body (e.g. blood pressure, body temperature, acid-base balance) are maintained at equilibrium, despite variations in the external conditions" Homeostasis is the maintenance of a stable internal environment within tolerance limits, this is the restricted range of conditions where cellular operations effectively work at a consistent rate and maintain life. These conditions include temperature, blood glucose levels, pupil diameter control and many more. Homeostasis actually means 'unchanging', but that is not a true description of biological systems. DYNAMIC EQUILIBRIUM is a more accurate description. (1) "An amoeba, a single celled organism, needs to be able to take in oxygen, food and nutrients and to excrete waste products. It needs a constant state of hydration and a controlled temperature for a happy life. Man is complex and multicellular but each cell has the same needs as the amoeba and we have developed complex mechanisms to provide each cell with all that it needs" (2) The human animal is a very complex multi-cellular organism in which the maintenance of life depends upon various
