(c) Total 4 __________________________________________________________________________________ klm Question 3 (a) GCE: Biology B – BYB4 June 2002 Mark across whole of two parts in (a) to credit the following possible points (structure) Distant object Close object Cornea suspensory ligament Ciliary Body - in tension - relaxed; - converges light/refracts/bends light; - tension relaxed; - contracts; - pulled thin; Lens - allowed to become fatter/more spherical; - the
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exchange rates are used to express transactions in local currency in terms of U.S. dollars and vice versa. For example‚ if the exchange rate is $1 = 1.65 DM (Deutsche mark)‚ and if one wishes to change 100 U.S. dollars into Deutsche marks‚ one will receive $100 ( 1.65 = 165 DM‚ and if one wishes to change 100 DM to U.S. dollars‚ one will receive 100 DM/1.65 = $60.61. 2. A foreign currency transaction occurs when a transaction is denominated in a currency other than that of the firm. For example
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the observed process of change in the species structure of an ecological community over time. Within any community some species may become less abundant over some time interval‚ or they may even vanish from the ecosystem altogether. Similarly‚ over some time interval‚ other species within the community may become more abundant‚ or new species may even invade into the community from adjacent ecosystems. This observed change over time in what is living in a particular ecosystem is "ecological succession"
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SCIENCE CELL – STRUCTURE AND FUNCTIONS Cell – Structure and Functions Cell as the Basic Unit of Life The cell is the basic structural and functional unit of all living organisms. It is the smallest part of the body of an organism‚ is capable of independent existence and is able to perform the essential functions of life. Discovery of the Cell Robert Hooke observed cork cells under a simple microscope designed by him. He observed compartments resembling honeycombs and each compartment
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How Primary Structure Determines Protein Function Proteins are everywhere. As enzymes‚ they catalyse chemical reactions. There are many different types of proteins: carrier and channel proteins which transport substances‚ receptor proteins which are recognition site for antibodies and hormones‚ structural proteins which support cells and tissues‚ and hormones which transmit information. Proteins are big molecules with large molecular masses that are made up of many amino acids; they’re‚ essentially
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carbon dioxide from the tissues back to the lungs. In order to function most efficiently‚ haemoglobin needs to bind to oxygen tightly when the oxygen concentration is high in the lungs and be able to release oxygen rapidly in the relatively low partial pressure in the tissues. I will be comparing the structure and function of haemoglobin with the structure and function of collagen‚ which is a structural protein. Collagen’s functions are quite different from those of globular proteins such as enzymes;
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Structure and Function of the Human Digestive System By Caitlin Ong Organs of the Digestive System Mouth Structure: The mouth consists of the upper and lower jaw‚ that contain gums which hold teeth‚ the roof of the mouth is the palate and the tongue occupies the floor of the mouth. The salivary glands have ducts that open in the mouth. Function: The mouth is where the first step of digestion begins. Known as mechanical digestion‚ this involves chewing with your teeth to break the food
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ESSAY ‘The structure and importance of the plasma membrane found within and around all cells’ The plasma membrane surrounds all eukaryotic and prokaryotic cells. Eukaryotic cells have membrane bounded organelles whereas prokaryotic cells do not. The plasma membrane forms the boundary between the cell cytoplasm and the environment. Its function are to allow different environments to be established inside and outside the cell. It also controls the movement of substances into and out of the cell.
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How the structure of proteins are related to their functions Rachel Morris The basic building blocks of proteins are amino acids‚ the biuret reaction tests for protein. A solution of sodium hydroxide is added to a sample then a few drops of copper sulphate solution‚ if positive – the solution will turn mauve. There are 20 different amino acids and they can be joined in any order. Therefore there can be many different functions. A protein consists of one or more polypeptide chains (a polypeptide
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Marine Ecosystems are the largest systems on the planet‚ covering over 70 percent of the Earth’s surface and constituting over 99 percent of the living space on the planet (area x depth). These vast ecosystems are composed of many different habitats which extend from the near shore regions to continental shelves and the deep ocean. They are home to millions of species and provide food‚ income‚ protection‚ and many other vital ecosystem services to billions of people around the world. ECOLOGICAL
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