This chapter considers the exchange of nutrients and waste products between the cells and the environment of unicellular organisms and simple animals. Examples include sponges. These can be accomplished by simple diffusion across the cell membranes. The chapter cites diffusion as a random process in three dimensions, the time required for equilibration increases rapidly with increasing distance. In more complex animals, diffusion of nutrients by itself would not suffice to permit adequate exchange of nutrients and waste products, as most cells are separated from the external environment by a considerable distance. The chapter describes the organization of the circulation, its gross anatomy, the structure of the blood vessels, and their innervation. One of the primary functions of the circulatory system is to promote the carriage of oxygen and nutrients to the cells and remove the products of metabolism.
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Chapter
Introduction to the cardiovascular system
Chapter
The chemical constitution of the body
This chapter describes the human body as consisting largely of four elements: oxygen, carbon, hydrogen, and nitrogen. It shows that about 70 percent of the lean body tissues is water, while the remaining 30 percent made up of organic material (i.e. molecules and minerals). The principal organic constituents of mammalian cells are the carbohydrates, fats, proteins, and nucleic acids, which are built from smaller molecules belonging to four classes of chemical compounds: sugars, fatty acids, amino acids, and nucleotides respectively. The chapter outlines the principal minerals found in tissues: calcium, phosphorus, potassium, and sodium. It gives an approximate indication of the chemical composition of the body for a young adult male, noting that there is individual variation and that the proportions of the various constituents vary between tissues and change during development.
Chapter
The physiology of high altitude and diving
This chapter describes the physiology of the cardiovascular and respiratory systems under the stresses imposed by changes to ambient pressure. It refers to the physiological adaptations which occur when a person experiences the reduced atmospheric pressure of high altitudes. It also looks at the respiratory problems associated with high ambient atmospheric pressures, such as those experienced by divers. The chapter clarifies how atmospheric pressure decreases with altitude and how the partial pressure of oxygen in the inspired air falls progressively with increasing altitude as the fraction of oxygen in the air does not change. The hypoxia of altitude can be divided into acute hypoxia, which is experienced by subjects who have been exposed to high altitude for a few minutes or hours, and chronic hypoxia, which is experienced by people living for long periods at high altitude or by mountaineers who have become acclimatized to high altitude.
Chapter
Oxidation and reduction
This chapter focuses on oxidation and reduction. When the muddy sediments at the bottom of a river or lake are disturbed, two things are often noticed. First, there is a smell of rotten eggs, indicative of the generation of hydrogen sulfide. Secondly, the colour of the sediment may change from a red-brown at the surface to a dark brown-black below. Both of these observations are linked to a lack of oxygen. In purely chemical terms, the absence of oxygen in these sediments has resulted in the reduction of sulfur(VI) to sulfur(-II); that the reduction has been carried out by bacteria does not necessarily alter the chemical result. It is not only the sediments which can become devoid of oxygen. The water in lakes, and even the bottom waters of fjords, can reach this state if the oxygen is consumed by organisms and if the chemical processes faster than it can be replaced.
Chapter
Alcohols, Phenols, Ethers, Organic Halogen Compounds, and Amines
Chris Rostron
This chapter considers a number of functional groups, such as oxygen in the air and oxygen as a component of water. It is also found in many molecules. Functional groups are made, changed, and destroyed in chemical reactions. The chapter highlights oxygen's value as a component of functional groups that stems from its high electronegativity, which means that it strongly attracts electrons. The chapter describes the hydroxyl group as the most biologically significant functional group as it is one of the most widely occurring in nature, being present in carbohydrates, proteins, and nucleic acids. The properties of carbohydrates, for example, are essentially a combination of hydroxyl chemistry and the chemistry of aldehydes and ketones.
Chapter
Transport of Oxygen and Carbon Dioxide in Body Fluids
(with an Introduction to Acid–Base Physiology)
This chapter discusses the transport of oxygen and carbon dioxide in body fluids. It also introduces the concept of acid-base physiology and shows how this focuses on the regulation of pH and the functions of respiratory pigments in animals. Haemoglobins, haemocyanins, haemerythrins, and chlorocruorins, also known as the four chemical categories of respiratory pigments, resemble the properties of the enzyme proteins. The chapter mentions the oxygen equilibrium curve as a key tool for understanding the function of a respiratory pigment. It also explores the process of carbon dioxide transport by acknowledging the other chemical forms in which carbon dioxide exists in the blood.
Chapter
The Chemical and Physical Environment
This chapter looks into how marine organisms respond to changes in the chemical and physical aspects of their environment. Measures of organismal response include whole organism, behavioral, physiological, and biochemical factors. Marine species evolve to function at the highest efficiency in a given thermal regime. Moreover, changes to salinity present challenges to marine species because of diffusion and osmosis. The chapter explains that organisms respond to environmental change by reaching a new equilibrium through a process known as acclimation. It then considers the factors of temperature, salinity, oxygen, and light with regard to the acclimation of species in an environment.
Chapter
The thermodynamic background
This chapter shows that reactions tend to proceed in the direction of decreasing Gibbs energy and towards a composition summarised by an equilibrium constant. It emphasises the importance of the thermodynamic criteria for spontaneous change and equilibration, as is central to an understanding of the molecular processes that occur in cells. The chapter begins by stating that, at constant temperature and pressure, a reaction mixture tends to adjust its composition until its Gibbs energy is a minimum. From there, the chapter discusses the variation of reaction Gibbs energy with composition. Reactions at equilibrium are then explored. The chapter ends with a case study involving the binding of oxygen to myoglobin and haemoglobin.
Chapter
Oscillatory reactions in flow systems
This chapter explores the gas-phase reaction between hydrogen and oxygen, which illustrates the influence of branched-chain kinetics on simple combustion reactions. It clarifies how chain branching provides feedback and is proven to be a classic nonlinear kinetic system. It also discusses p-Ta
ignition limits in closed vessels, which are considered vessels of parametric sensitivity. The chapter describes two distinct modes of reaction that depend on the exact initial pressure and temperature: slow reaction and ignition. It points out that in slow reaction, the rate of conversion of reactants to the product H2O may be imperceptibly low, while in ignition the reaction proceeds on a millisecond timescale with explosive force and a considerable temperature excursion.
Chapter
Cardiorespiratory Bases for Performance
This chapter provides a background on cardiovascular and respiratory systems from the perspective of the athlete. Their most important function is to deliver oxygen to the exercising muscles and to remove carbon dioxide, while maintaining blood flow to vital organs. The chapter explains how the cardiovascular system matches the blood flow to skeletal muscle to its metabolic rate. It also analyszes two circuits of the cardiovascular system that are arranged both in parallel and in series: pulmonary circuit and systemic circuit. The chapter explains that the pulmonary circuit conducts blood from the right side of the heart to the lungs and back to the left side of the heart. It clarifies how the systemic circuit conducts blood from the left side of the heart to all the tissues in the body and back to the right side of the heart.
Chapter
Introduction
This chapter considers underlying molecular and cellular elements and the link between structure and function in physiology to provide an understanding of the structures within the body. It discusses the body in terms of the hierarchical nature of organization from the molecular level through to the organismal level. It also highlights the elemental composition of the vast majority of the body which is formed from carbon, oxygen, hydrogen, oxygenydrogen, carbon, and nitrogen. The chapter analyzes an individual's body weight in terms of body composition, which is accounted for by water and is found in a variety of compartments. Given that water accounts for most of an individual’s body weight, the chapter looks in depth at the forms this water takes. It explains that the water within the body has a variety of solutes dissolved in it that. These form extracellular fluid and intracellular fluid, each of which has a unique composition.
Chapter
Cardiovascular physiology
This chapter focuses on the cardiovascular system. This provides cells with oxygen and nutrients and transports metabolic waste products away from cells. The chapter talks about the heart and the extensive system of vessels known as the circulatory system. It explains that the heart acts as a pump while the circulatory system acts as a transport system for blood. The chapter highlights the normal functioning of the cardiovascular system which is essential in order to maintain an appropriate cellular environment for all cells in the human body. It emphasizes that the heart can be thought of as a pump that ejects blood into the pulmonary and systemic circulations.
Chapter
The respiratory system
This chapter details the principal role of the respiratory system, which is to provide an exchange of gases between the body and the environment. It outlines the functions of the respiratory system, such as its contribution to the maintenance of plasma pH and the production of sound. It also explains how the respiratory system ensures that adequate amounts of oxygen are delivered to tissues and carbon dioxide is efficiently removed when exchanging gases in a variety of environmental challenges. The chapter talks about the paired lungs that sit inside the thorax, which are formed from a series of bifurcations of a single trachea. It details how air enters the lung by a suction pump, wherein inspiration results in an increase in volume and a decrease in pressure inside the lungs.
Chapter
Introduction to Oxygen and Carbon Dioxide Physiology
This chapter introduces oxygen and carbon dioxide physiology. It starts with the properties of gases in gas mixtures and aqueous solutions. The respiratory gases move from place to place principally through the mechanisms of simple diffusion and convection (bulk flow). Simple diffusion is one of the two principal mechanisms of respiratory gas transport, while transport by bulk flow occurs when a gas mixture or an aqueous solution flows and gas molecules in the gas or liquid are carried from place to place by the fluid flow. Additionally, the concept of chemical potential plays a significant role in understanding respiratory gases and gas transport. The chapter also considers the concept of oxygen cascade in line with understanding the transport of O2 from the environment to the mitochondria of an animal.
Chapter
Diving by Marine Mammals
Oxygen, Carbon Dioxide, and Internal Transport AT WORK
This chapter looks into the science of diving by marine mammals by considering the interplay between oxygen, carbon dioxide, and internal transport. Advances in technology have provided new options for getting time and depth information on the swimming of the Weddell seal. The size of a diving mammal's total O2 store is a key determinant of how long the animal can stay submerged. Moreover, circulation holds a special place in the chronicles of diving physiology because the very first physiological observations on diving were measures of heart rates. The chapter also looks into the notion of metabolism during dives and the aetiology of decompression sickness.
Book
Richard W. Hill, Daniel J. Cavanaugh, and Margaret Anderson
Animal Physiology is composed of six parts. Part I looks at the fundamentals of physiology including animal, environment, molecules, cells, genomics, proteomics, physiological development, and transport of solids and water. Part II covers food, energy, and temperature. It looks at topics such as nutrition, feeding, digestion, energy metabolism, aerobic and anaerobic forms of metabolism, thermal relations, and food. The next part looks at integrating systems: neurons, synapses, sensory processes, nervous system organization, biological clocks, endocrine and neuroendocrine physiology, reproduction, and integrating systems in action. The next part covers movement and muscle. Part V is about oxygen, carbon dioxide, and internal transport. The final part of the book looks into water, salts, and excretion.
Chapter
Oxidation of activated carbon–hydrogen bonds
This chapter evaluates the oxidation of activated carbon–hydrogen bonds. During the course of an oxidation, hydrogen can be removed in three ways, as either H+, H*, or H-. Normally, it is beneficial to have a functional group which stabilises the carbon left behind by such removal of hydrogen. As such, the chapter considers the hydrogen atom that is lost, activated by the functional group. It begins by looking at oxidation adjacent to oxygen. This is the most useful and widespread area of oxidation, as it encompasses the alcohol-aldehyde-carboxylic acid sequence which is used so often in synthesis. The chapter then studies oxidation adjacent to a carbon–carbon multiple bond, a carbonyl group, and nitrogen, as well as the oxidation of phenols and the formation of quinones.
Chapter
Oxidative cleavage reactions
This chapter focuses on reactions which lead to the cleavage of carbon–carbon single (and multiple) bonds and the introduction of new bonds between carbon and an electronegative element, such as oxygen. It also considers the similar process which leads to the cleavage of bonds between carbon and other electropositive elements such as boron or silicon. The chapter begins by looking at the oxidative cleavage of carbon–carbon double bonds. Clipping an alkene to furnish two carbonyl compounds is most readily carried out with ozone (O3): the four substituents that were attached to the alkene end up as substituents on the two new carbonyl containing compounds. The chapter then studies the oxidative cleavage of carbon–carbon sigma bonds; of carbon–boron and carbon–silicon bonds; and of carbon–halogen bonds.
Chapter
Reduction of carbon–heteroatom double and triple bonds
This chapter explores the reduction of carbon–heteroatom double and triple bonds. There are many functional groups based on multiple bonds between carbon and either oxygen or nitrogen. The chapter demonstrates some of the corresponding reduction reactions of these functional groups. It begins by looking at the reduction of carbon–nitrogen π-bonds. Nitriles contain a strong triple bond between carbon and nitrogen. In terms of reactivity, nitriles are susceptible to nucleophilic attack and therefore reduction of these groups is easily effected by 'hydride' reducing agents. The chapter then considers the reduction of carbon–oxygen π-bonds. The reduction of aldehydes to primary alcohols and ketones to secondary alcohols is normally easy to accomplish using sodium borohydride or lithium aluminium hydride.
Chapter
The Group 16 elements
This chapter discusses the essential features of the chemistry of the Group 16 elements: oxygen, sulfur, selenium, tellurium, polonium, and livermorium. All of these are nonmetals, apart from polonium, the heaviest member of the group. The chapter observes the rich variation in the structures of the compounds they form. It highlights that oxygen differs significantly from the other members of the group: it is the most electronegative element in Group 16 and is the only gas. Then it looks at hydrides, halides, and metal oxides. The chapter also looks at metal sulfides, selenides, tellurides, and polonides. Next, it tackles compounds formed between oxygen and its congeners in Group 16.
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