Our sense organs 45

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Neurons are the building blocks of the brain. They possess the same genes as other body cells, they are constructed along similar lines, and they are kept alive by the same biochemical processes which support other cells. But they differ in some essential aspects, making them the most extraordinary cells in a living organism. The differences include shape, type of cell membrane, and the presence of a structure known as a synapse. The cell membrane has the ability to produce neural signals, and in the synapses these signals are carried to other nerve cells by means of transfer substances called neurotransmitters. During the development of the organism from a fertilised ovum, neurons are formed at the astounding rate of 250,000 per minute over nine months. It used to be thought that neurons do not subdivide after an embryo is fully developed. Thus, the number of nerve cells formed up to the moment of birth had to last one’s entire lifetime. Recent evidence indicates that at least some nerve cells may be replaced in the adult organism after all. With between ten and fifty thousand connections per nerve cell, the entire system forms an immeasurably complex branched network. If it were possible to describe it as a circuit diagram, then even if each neuron were represented by a single pinhead, such a circuit diagram would require an area of several square kilometres! Compare this to the complex engineering drawings which are often produced according to the DIN-A0-Format on only one square metre (841 mm x 1189 mm). Such a circuit diagram of the brain would be several hundred times more complex than the entire global telephone network. In reality, nobody really knows anything much about the internal connections of the brain. The total length of the nerve fibres in the greater brain (cerebrum) is about 500,000 km, with some authors even estimating it to be as much as one million km. <strong>Our</strong> “command centre“, the brain, would be useless if there were no links to the body. Outside of the brain the total length of nerve fibres is 380,000 km, which is equal to the distance of the moon from the earth. They form a branching network throughout the body, continually carrying information and commands to 82 and fro between the brain and all our other parts. In places the thickness of these fibres is only one thousandth of a millimetre, but messages travel along them at a speed of about 40 metres per second or 144 km/h. This is equal to the speed of a hurricane-force wind (force 12). Processing speed: The incredibly dense neuronal network can process signals at a very high rate. The brain can do 10 18 = 1 million million million computations in a second, which is a hundred million times as fast as the fastest super computer at time of writing (10 10 calculations per second). The most fascinating aspect, however, is not the actual physical performance of the brain, but its ability to process these unimaginably vast quantities of information in unique ways which we cannot yet fully comprehend. Energy consumption: The brains of dogs and cats are responsible for between five and six per cent of the energy consumption of the entire animal. This is more or less true for all mammals (regardless of body size), with the exception of primates (apes, monkeys, etc.). In rhesus monkeys, the percentage is about nine, but for humans it is an impressive 20 per cent. <strong>Our</strong> brain requires about 20 Watts, which is one fifth of the energy (100 Watts) consumed by the whole body. The brain of a growing embryo requires a much greater proportion of energy, namely 60 per cent. Structure: The cerebrum occupies the greater part of the brain’s volume. It consists of two halves or hemispheres, each of which is responsible for the functioning of the opposite half of the body. The two halves are connected via the corpus callosum, which is essentially a broad cable made up of 300 million nerve fibres. Each hemisphere is covered by a three millimetre thick layer of nerve cells. This layer, the cerebral cortex, is intensely convoluted and has a total surface area of about 2,200 cm 2 . The cortex 1 enables us to organise, to remember, to understand, to com- 1 Cortex: Latin cortex = bark, crust, shell. The word cortex is used anatomically to indicate the outer layer or surface of an organ. In the brain there is the cerebral cortex, and the cerebellar cortex; the kidneys have the renal cortex.
Corpus callosum Anterior commissure Thalamus with anterior nucleus Olfactory bulb with olfactory nerves Optic chiasma Pituitary gland Pons Spinal medulla Medulla oblongata Cerebellum Pineal body Great cerebral vein Sensory cortex Central sulcus Motor cortex Vertical section through the brain 83
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1 st English edition 1999 2 nd Expa
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Contents Foreword .................
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Foreword What would you expect from
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Part 1: Man - an ingenious construc
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The eye - our window to the outside
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the inside of the eyeball. It conta
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➨ ➨ ➨ not mean that we can se
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eyes. There will be no more death o
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Malleus Head Long (lateral) process
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amplitudes. The pressure exerted by
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Whispering 25 Spacious office 50 Mo
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less viscous liquid, called the per
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The sense of smell - beyond words F
Page 32 and 33: finest detail, using plenty of imag
Page 35 and 36: The sense of taste - not just for c
Page 37: self will serve believers as his gu
Page 40 and 41: A section of human skin. The layers
Page 42: 3 In addition to sweat, the skin al
Page 46 and 47: Heaven: a) Heaven is a place where
Page 49 and 50: The heart - more than a high-tech p
Page 51 and 52: from the heart via the arteries. Th
Page 53 and 54: Foetal circulatory system. Neonatal
Page 55: “shunted on a siding” as far as
Page 58 and 59: 6 Transportation of hormones: The b
Page 60 and 61: One cell contains 32 pg (1 picogram
Page 62 and 63: each case. We can only stand amazed
Page 64 and 65: The Bible and blood: Having explore
Page 67 and 68: The kidneys - marvels of filtration
Page 69: ➡ ment, followed by the thin loop
Page 72 and 73: The cells - our body’s 100 millio
Page 75 and 76: DNA - information storage technolog
Page 77 and 78: total anatomy and physiology of a h
Page 79: The structure of the DNA molecule:
Page 84 and 85: municate, to evaluate, and to be cr
Page 86 and 87: Motor cortex - body movements The
Page 88 and 89: The fact that Archimedes had hands
Page 91 and 92: Body, soul, and spirit - man is mor
Page 93 and 94: a) A small cube lies in the corner
Page 95 and 96: MAN’S STRUCTURE Monism Dualism Tr
Page 97 and 98: explained in terms of a technologic
Page 99 and 100: What is man? Having learned of the
Page 101 and 102: Genesis 1:28: “God blessed them a
Page 103 and 104: TEKEL, PARSIN. This is what these w
Page 105 and 106: with Abraham (Gen 15:7-21, 17:3-14)
Page 107 and 108: Does God also have sense organs? We
Page 109 and 110: 109
Page 111 and 112: Every person - known to God? Job sa
Page 113 and 114: - a distorted image evolutionary th
Page 115 and 116: A very special man: Jesus Today man
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Page 119 and 120: All unbelief is sin, as we read in
Page 121 and 122: water here will soon be death’s p
Page 123 and 124: single set yet constructed, Cameron
Page 125 and 126: en, but only he who does the will o
Page 127 and 128: engines and at 7.16 metres diameter
Page 129 and 130: Personal testimonies: Jesus found t
Page 131 and 132: friends whom I could consult. The b
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133
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Getting your name in the “Book of
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sheep... I am the good shepherd; I
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to make sure that the entire Word o
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Beloved of God Today many people al
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Man in heaven: sharing the glory of
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On the third of June 1998, possibly
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something special. The first night
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The Empress Elisabeth of Austria, b
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Jesus prays to His Father in John 1
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© Copyrights and acknowledgements:
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Our sense organs 45

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