1. INTRODUCTION All biological activities depend on metabolic energy, and thus understanding why rates of metabolism vary is of fundamental importance. A major factor affecting meta- bolic rate is body size. Respiratory metabolic rate (R) typically scales with body mass (M) according to the power function R=aM, where a is a normalization constant (antilog of the intercept in a log-log plot) and b is the scaling exponent (slope in a log-log plot). Rubner (1883) observed that the scaling exponent b was 2/3 in dogs of different size, which he explained using the theory of Sarrus & Rameaux (1839: cited in McNab 2002). According to this theory, to maintain a constant body temperature, endothermic animals must metabolically produce enough body heat to exactly balance the amount of heat lost through their body surface. Therefore, since body surface scales as M, so should metabolic rate. However, in broader comparisons of different species of mammals, Kleiber (1932) found that b was closer to 3/4 than 2/3. Since that time, it has been commonly assumed that b is typically 3/4, a generalization known as 'Kleiber's h e law' or the 3/4-power law' (Brody 1945; Hemmingsen

1. INTRODUCTION All biological activities depend on metabolic energy, and thus understanding why rates of metabolism vary is of fundamental importance. A major factor affecting meta- bolic rate is body size. Respiratory metabolic rate (R) typically scales with body mass (M) according to the power function R=aM, where a is a normalization constant (antilog of the intercept in a log-log plot) and b is the scaling exponent (slope in a log-log plot). Rubner (1883) observed that the scaling exponent b was 2/3 in dogs of different size, which he explained using the theory of Sarrus & Rameaux (1839: cited in McNab 2002). According to this theory, to maintain a constant body temperature, endothermic animals must metabolically produce enough body heat to exactly balance the amount of heat lost through their body surface. Therefore, since body surface scales as M, so should metabolic rate. However, in broader comparisons of different species of mammals, Kleiber (1932) found that b was closer to 3/4 than 2/3. Since that time, it has been commonly assumed that b is typically 3/4, a generalization known as 'Kleiber's h e law' or the 3/4-power law' (Brody 1945; Hemmingsen

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter11: The Blood

Section: Chapter Questions

Problem 1SQE

See similar textbooks

Similar questions

O, saturation curve is shown beloww for hemoglobin at various pHs. Detail this Bohr effect from the molecular perspective. Be sure to include discussion of what causes this (i.e. specific amino acids), why the curves are right shifted with decreasing pH, and why this is logical in delivery of 02 to areas of higher demand. 100 Myoglobin 80- pH 7.6 60 pH 7.4 pll 7.2 40- pH 7.0 pH 6.8 20- Venous 0- 0. 20 10 60 80 Percent saturation
When the drug theophylline is administered for asthma, a concentration below 5 mg/L has little effect and undesirable side-effects appear if the concentration exceeds 20 mg/L. For a body that weighs W kg, the concentration when M mg is present is 2M/W mg/L and the constant that measures the rapidity at which the concentration falls is T = 6 h. If a 500-mg tablet of the drug is taken by a person weighing 70 kg, after how many hours should the second dose be taken so as to prevent the drug from falling below the effective concentration? About 6 hours Once a day About 12 hours O About 8 hours
Inorganic compounds of metallic mercury are presumed from metabolic studies to distribute uniformly after inhalation or ingestion with 8% going to the liver and 92% to the total body. Biological clearance of mercury in each of these tissues occurs by two compartments, 95% with a biological half-life of 40 days and the remaining 5% with a biological half-life of 10,000 days. For an intake of 1 MBq of 203Hg (Tr= 46.61 d). Determine the following 1. Total number of transformations in the Liver. 2. Total number of transformations in the total body.
op of Form Normal Levels of Substances in the Arterial Blood: pH 7.40 + 0.05 pCO2 (partial pressure of carbon dioxide) 40 mm Hg pO2 (partial pressure of oxygen) 90 - 100 mm Hg Hemoglobin - O2 saturation 94 - 100 % [HCO3-] 24 meq / liter Vignette #1: A 21-year-old noncompliant female with a history of type I (insulin-dependent) diabetes mellitus was found in a coma. Her blood glucose was high, as well as her urine glucose, urine ketones, and serum ketones. Her serum bicarbonate was < 12 mEq/L. Her respiration was exaggerated, and her breath had an acetone odor. Her blood pressure was 90/60 and his pulse weak and rapid (120). 1. Define noncompliant. 2. Is this person experiencing ketoacidosis or insulin shock? Explain your answer. 3. Why is the serum bicarbonate low? 4. What is the acid-base status of this individual? 5. What are the causes of the dyspnea, hypotension, and tachycardia? 6. What type of treatment does this person need?…
An analgesic drug was given to an elderly patient (70 kg body weight) by IV bolus injection at a dose of 800 mg. The drug has apparent volume of distribution of 21 L, and elimination half-life of 6 hours. Calculate the metabolism rate constant (Km) if you know that 80 % of the drug is metabolized in the liver and 20 % is excreted unchanged in urine
In the human body, blood vessels can dilate, or increase their radii, in response to various stimuli, so that the volume flow rate of the blood increases. Assume that the pressure at either end of a blood vessel, the length of the vessel, and the viscosity of the blood re- main the same, and determine the factor Ralated/Rpormal by which the radius of a vessel must change in order to double the volume flow rate of the 79. blood through the vessel.
Measurements of oxygen binding by whok human blood, at 37 °C, at pH 7.4, and in the presence of 40 mm Hg of CO, and normal physiological lkvels of 2,3-BPG (5 mmol/L of cells), give the following: Po, (mm Hg) % Saturation (=100 x Yo) 10.6 10 19.5 30 27.4 50 37.5 70 50.4 85 77.3 96 92.3 98 (a) From these data, construct a binding curve, and estimate the percent oxygen saturation of blood at (1) 100 mm Hg, the approximate partial pressure of O, in the lungs, and (2) 30 mm Hg, the approximate partial pressure of Oz in venous blood. (b) Under these conditions, what percentage of the oxygen bound in the lungs is delivered to the tissues? (c) Using the data in Figure 7.27, repeat the calculation of part (b) if the pH drops to 6.8 in capillaries but goes back to 7.4 as CO, is unloaded in the lungs.
Acetazolamide is a drug which inhibits carbonic anhydrase. Carbonic anhydrase participates in regulation of the pH and bicarbonate content of a number of body fluids. Figure 2 shows the experimental curve of initial reaction velocity (as percentage of Vmax) versus [S] (concentration) for the carbonic anhydrase reaction. The graph also shows the curve in the presence of acetazolamide. 100 No inhibitor 50 Acetazolamide 0.2 0.4 0.6 0.8 (S] (mM) Figure 2 (i) Compare the maximal velocities and Michaelis Menten constants of the enzyme in the absence and the presence of the inhibitor acetazolamide. Determine the nature of inhibition by acetazolamide. Explain your answer. (*"A JO %) A
A radiolabeled glucose solution is utilized as a nutrient source for a human myocyte in order to investigate the metabolic response under several conditions. This system was subjected to different conditions, and the CO₂(g) emitted is captured using carbon sequestration apparatus. The radioactivity of the sequestered gas is then measured. The following are the conditions (a to d). Arrange them in terms of expected radioactivity of the captured gas noting that higher radioactivity corresponds to increased concentration of CO2(g). Unless otherwise stated, all of these conditions are at room temperature. Explain the trend in 4 to 5 sentences. a. 1.0 M phosphate buffer, pH = 6.8 b. 0.1 M NaF c. 0.1 M citric acid d. 100 °C
← http: S Scho S Grac SEX S Show S Thin D BCPS Links U2L S U2L http SU2L S Job S MD S Try bcps.schoology.com/common-assessment-delivery/start/6343073236?action=onresume&submissionid=968149682 Show What You Know: Cellular Respiration (minor summative) Which of the following formulas is the balanced chemical equation for cellular respiration? O 6CO2 + 6H2O -> C6H12O6 + 602 C6H1206+6 02-> H2O + CO2 + 6 ATP O 02 C6H1206-> CO2 + H2O + ATP O C6H1206+6 02-> 6 H2O + 6 CO2+36ATP S Try O Goo W Job G WH 4 1 2 3 Sign out
In active muscle cells, the pO2 is about 10 torr at the cell surface and 1 torr at the mitochondria(the organelles where oxidative metabolism occurs). Calculate the percentage of bound oxygentransported to the mitochondria of muscle cells by myoglobin (KD = 2 torr).
MEASURING CO2 PRODUCTION IN ANIMALS (Effect of Temperature & Effect of Size) make a introduction and importance to physiology. please include citation.