Medium 9789380386638

A Book of Biotechnology

Views: 272
Ratings: (0)
This Book of Biotechnology has been written for Graduate and Post Graduate students of Biotechnology of various universities of India. It is also useful to the students, researchers of Botany, Pharmacology, Zoology and Microbiology. The contents of this book have been divided into fourteen chapters.

List price: $24.95

Your Price: $19.96

You Save: 20%

Remix
Remove
 

16 Slices

Format Buy Remix

Blank Page

PDF

 

Prelims

PDF

 

Chp-1

PDF

Chapt er

Chapter

1

MICROSCOPY

INTRODUCTION

Almost all cells are too small to be examined directly with the human eye and so, our knowledge of cells has depended very much on microscopic techniques for magnifying them.

The history of cell biology is an excellent example of the effect of one scientific discipline on another. The improvements in microscopy produced by developments in physics have been closely correlated with the expansion of cell biology. It is interesting to compare the appearance of the microscope used by Robert Hook in the seventeenth century with that of modern light and electron microscope. The magnifications attainable by these microscopes range from X 100 to X 400,000. In addition, several different kinds of microscopy are available, and many techniques have been developed by means of which specimens can be prepared for examination.

Each type of microscopy and each method of preparing specimens for examination offers advantages for demonstration of specific morphological features.

 

Chp-2

PDF

68

A BOOK

OF

BIOTECHNOLOGY

Chapt er

Chapter

CHEMISTRY

FOR

2

BIOLOGISTS

INTRODUCTION

Chemistry is the science that deals with the composition and structure of matter and with the transformations that matter undergoes. Chemistry is a rather broad field; at one extreme, in theoretical chemistry and spectroscopy, it borders on physics, and at the other extreme, in organic chemistry, it borders on biochemistry and biology.

ATOMS, MOLECULES, ELEMENTS, COMPOUNDS

All substances, whether gas, liquid, or solid, have certain fundamental characteristics in common. If one could break down any substance into its smallest elemental units, it would be composed of atoms. Although it is difficult to observe atomic structure, atoms are known to consist of a mass of positively charged protons, noncharged (or neutral) neutrons, tiny negatively charged electrons, and other even smaller subparticles. An atom has equal numbers of electrons and protons; thus it has a total charge that is zero. When an atom loses or gains electrons it becomes a negatively or positively charged ion (e.g., Na+, Cl–). The protons and neutrons are found in a central nucleus, and the electons float around the nucleus, like negatively charged satellites attracted to a positively charged planet.

 

Chp-3

PDF

Chapt er

Chapter

3

THE SCIENTIFIC METHOD, LIVING

ORGANISMS AND THE GROUPS OF

MICROSCOPIC ORGANISMS

INTRODUCTION

Since earliest times man has been trying to solve the mysteries of nature to satisfy his curiosity.

Why does iron rust ? What happens to coal when it burns? How does a mighty tree grow out of a tiny seed? Why to certain things float on water while others sink ? How do living things differ from non-living objects? His method of finding answers to all such questions has followed a set pattern; careful observation of the phenomenon; derivation of inferences from the observations; and experimentation for the verification of inferences. The knowledge thus gained is empirical; it merely describes facts. The foundations of science were laid by classifying and correlating various facts. Science may be defined as knowledge classified, correlated, and generalized into a system. In short, it is the systematized knowledge. A mere collection of facts is no more science than a pile of bricks in a house.

 

Chp-4

PDF

130

A BOOK

OF

BIOTECHNOLOGY

Chapt er

Chapter

4

PURE CULTURE METHODS FOR THE

STUDY OF MICROORGANISMS

INTRODUCTION

The ability to determine the characteristics of a microorganism depends in large part on being able to grow pure cultures (cultures containing only that organism) of that microbe for study.

To cultivate, or culture miroorganisms it is necessary to establish a suitable environment, one in which the particular microbe can survive and reproduce. For each type of microorganism there are minimal nutritional requirements, tolerance limits for a variety of environmental factors, and optimal conditions for growth. By understanding the growth requirements of a given microbial species, it usually is possible to establish the necessary conditions in vitro

(within glass or plastic culture vessels) to support the optimal growth of that microorganism.

Cultures are routinely grown in the clinical microbiology laboratory to aid in the determination of the cause of a patient’s disease. Water quality testing laboratories culture microorganisms to determine the safety of the water supply. Various industries grow pure cultures of microorganisms in huge vessels called fermentors to produce numerous products of economic value.

 

Chp-5

PDF

MUSHROOM CULTURE

Chapt er

Chapter

159

5

MUSHROOM CULTURE

INTRODUCTION

Mushrooms have fascinated man since time immemorial. Some of them are a good source of food. About 2000 species of edible mushrooms have so far been reported from all over the world but only a few species like Agaricus campestris, the common field mushroom; A. bisporus, a cultivated variety of Europe and North America; Lentinus edodes, the Shii–take of Japan; and

Volvariella volvacea, the paddy straw mushroom of China and South-East Asia are being cultivated on an extensive scale. In Europe and North America, the cultivation of common field mushroom has become a large industry. In Great Britain and America large quantities of mushrooms are available for canning and food manufacture as well as for direct consumption.

Several million pounds of the Shii–take are produced annually in Japan and China. In India, large scale mushroom cultivation is in progress but is confined to a few states like Himachal

Pradesh, Tamil Nadu, and Uttar Pradesh.

 

Chp-6

PDF

Chapt er

Chapter

6

MYCORRHIZAE

INTRODUCTION

The root hairs and other surfaces of the young root do not constitute the chief absorbing surfaces in all plants. Exceptions to this situation are found in a number of kinds of plants in which the young, active portions of the roots are invaded by specific soil fungi. The resulting association is intimate and complex, and the combination of root and fungus is termed as a mycorrhiza (literally, “fungus root”).

WHAT IS A MYCORRHIZA ?

A mycorrhiza is mutualistic morphological and physiological association between a fungus and the root of some species of higher plant. These structures are formed as a result of the invasion of young roots by the hyphae of various species of fungi commonly found in forest soils.

It is likely that the great majority of land plants enter into this kind of relation with soil fungi. The mycorrhizal fungi are present in forest soil and become associated with seedlings that germinate there. Seedlings growing elsewhere frequently do not thrive because of the lack of mycorrhizae.

 

Chp-7

PDF

CHROMOSOMES

AND

DISEASE

Chapt er

Chapter

CHROMOSOMES

AND

191

7

DISEASE

INTRODUCTION

The congenital malformation called mongolism affects one in approximately 650. Ever since the condition was identified in the 1860’s by the British neurologist John Langdon Down, concerned physicians and investigators had been seeking its cause. For many years, Mongolism was described as a heredity disease, the result of some unknown effects in the “germplasm”.

Investigators dissatisfied with such vague explanations have argued the opposite view that the disease is environmental, and have correlated its incidence with accidents due to the developing embryo during gestation, that is, the period between conception and birth.

The explanation of mongolism is now at hand. The disease is neither typically hereditary nor environmental, as these terms are commonly employed. It arises from a defect in the mechanism by which the heredity material is passed on from parent to offspring. This leaves certain questions unanswered: for example, whether the defect in the genetic mechanism is itself hereditary or environmental in origin. The explanation is nonetheless of great significance, for it is among the first findings to come from direct investigation of the genetic apparatus of the human cell. The techniques of cell genetics have mostly been restricted to more easily studied cells of lower animals and plants.

 

Chp-8

PDF

212

A BOOK

OF

BIOTECHNOLOGY

Chapt er

Chapter

8

ENZYMES

INTRODUCTION

An enzyme (from the Greek word “enzymos” meaning “in yeast”) is a biocatalyst. It is partly or entirely a protein that can tremendously increase the efficiency of a biochemical reaction without itself being used up. Although a biochemical reaction will proceed to completion in the absence of an enzyme, the process would be extremely slow – so slow in fact, as to make life as we know it impossible. Thus, it is safe to assume that most reactions occurring in the cells are catalyzed by enzymes. The term “catalyst” is used by the physical chemist to denote a substance which alters the rate of a reaction. Consequently, negative catalysis is possible.

The word is used here in the popular sense, i.e., a substance which accelerates a reaction.

NATURE OF ENZYMES

Enzymes, being organic catalysts, have many of the properties of inorganic catalysts and thus can be characterized as follows :

1. Enzymes are active in extremely small amounts-that is, in a biochemical reaction only a small amount of enzyme is necessary to convert a large amount of substrate to product. The two terms substrate and product signify the starting and ending material of a reaction respectively. The number of moles of substrate converted per minute by

 

Chp-9

PDF

222

A BOOK

OF

BIOTECHNOLOGY

Chapt er

Chapter

PROTEINS

AND

9

NUCLEIC ACIDS

INTRODUCTION

The chemistry of nucleic acids, as expressed through the proteins, regulates the intricate biochemical properties of life and the dynamics of evolution. A most significant influence of proteins resides in the fact that many are functionally active as enzymes. The enzymes are vital for the rapid rate of biochemical reactions. Although many biochemical reactions will proceed to completion in the absence of enzymes, these reactions are extremely slow. Indeed, we could go so far as to say that enzymes and life are inseparable.

Two other important functions of proteins are as major natural hydrogen ion buffers and structural components of cells. Certainly many important characteristics of proteins led scientists to the chemistry of regulators of cellular information, the nucleic acids.

AMINO ACIDS AND AMIDES

The acid hydrolysis of protein molecule reveals that it is composed of smaller repeating units, the amino acids. With the exception of two secondary amino acids, the amino acids found in protein have the following general structure.

 

Chp-10

PDF

234

A BOOK

OF

BIOTECHNOLOGY

Chapt er

Chapter

10

CARBOHYDRATES

INTRODUCTION

Carbohydrates are a group of organic compounds containing the elements carbon, hydrogen, and oxygen, generally in the ratio of 1 : 2 : 1, with the general formula (CH2O)n (the n in the formula means that CH2O is repeated a certain number of times ; if 6 times, a molecule of glucose –C6H12O6 is formed.) One carbon bears a carbonyl group and the others hydroxyl groups. However, the definition of this group (as hydrates of carbon) has been broadened to include compounds containing nitrogen and sulphur, and compounds that do not conform to a strict 1 : 2 : 1 ratio of carbon, hydrogen, and oxygen. Carbohydrates, therefore, are considered to be polyhydroxy—aldehydes or polyhydroxy-ketones, and their derivatives.

The carbohydrates are derived more or less directly from carbon dioxide and water in photosynthesis. Sugar, starch, and cellulose are examples of carbohydrates that illustrate the importance of this class of compounds to life. Cellulose is the principal constituent of wood

 

Chp-11

PDF

246

A BOOK

OF

BIOTECHNOLOGY

Chapt er

Chapter

11

STAINING

INTRODUCTION

The subject of dyes or stains and methods of using them has become one of vast proportions.

The number of dyes available is enormous, and ways of employing stains are almost as enormous as the workers using a particular dye or combination of stains. The preparation and use of stains has all become a science in itself, and there exists a most valuable journal, Stain

Technology, devoted to these and related subjects. Experimenting with new dyes and new staining schedules is a most fascinating occupation, and there is a very great deal yet to be learned about stains and their utilization.

STAINS AND THEIR USE

Although stains were used as early as 1770 in the study of the structure of the wood, it was not until 1839 that Ehrenberg used them to study microbes. Their use depends upon the following properties :

1. The chemical must be chromogenic–in other words, it must possess colour – forming groups in its molecules.

2. The stain must exist as a salt in aqueous solutions–that is, it must break up (dissociate) into positively and negatively charged particles. These are called, respectively, cations and anions. For example, in the case of methylene blue, when placed in an aqueous medium the following chemical reaction occurs :

 

Chp-12

PDF

254

A BOOK

OF

BIOTECHNOLOGY

Chapt er

Chapter

12

CHROMATOGRAPHY

INTRODUCTION

Chromatography is an analytical technique for separating two or more chemical compounds in solution by taking advantage of the fact that they are removed from solution at different rates when the latter is percolated down a column of a powdered adsorbent or passed across the surface of an absorbent paper. This is one of the most significant and reliable methods used in the fields of chemistry and biological sciences to obtain and identify substances (such as proteins, chlorophyll pigments, etc.), in a high state of purity.

Chromatography, a term derived from the Greek words chroma, colour, and graphien, to record, was introduced by the Russian botanist Michael Tswett in 1906. He described the separation of a mixture of leaf pigments on a column of calcium carbonate.

CHROMATOGRAPHIC METHODS

In all the chromatographic techniques, difference in affinity involves the process of adsorption, or partition. In adsorption, the binding of a compound, to the surface of the solid phase takes place. In partition the relative solubility of a compound in two phases, results in the partition of the compound in two phases.

 

Chp-13

PDF

258

A BOOK

OF

BIOTECHNOLOGY

Chapt er

Chapter

13

TRACER TECHNIQUE—THE USE

OF ISOTOPES AS TRACERS

INTRODUCTION

The atoms of most chemical elements exist in more than one variety. Each kind of a given element has a different atomic weight, but all of them carry the same nuclear charge. For example, there are three different kinds of magnesium atoms with atomic weights of 24, 25, and 26 respectively. Such different varieties of atoms of a given element are called isotopes.

Differences in the chemical behaviour of two isotopes of the same element are so slight as to be barely detectable, and ordinarily they cannot be separated by chemical methods. The chemical properties of all isotopes of a given element are virtually identical, because all have the same electronic configuration ; one isotope differs from another only in the constitution of the atomic nucleus which is composed of protons and neutrons.

RADIOACTIVE ISOTOPES

In addition to the stable isotopes described above, there are many radioactive isotopes of certain heavy elements such as uranium and radium occur in nature. The atoms of many elements not normally radioactive may be made so by bombardment with various types of elementary particles such as neutrons, protons, deutrons, and alpha particles. Such bombardments are usually accomplished with the aid of a cyclotron or a uranium pile reactor.

 

Chp-14

PDF

262

A BOOK

OF

BIOTECHNOLOGY

Chapt er

Chapter

14

SPECTROPHOTOME TRY

INTRODUCTION

Coloured substances absorb certain wavelengths of light and reflect or transmit rest of it. A material or a group which absorbs ultraviolet or visible light is known as a chromophore

(coloured substance). Each chromophore is characterised by an absorption maximum, which is the radiation of a specific wavelength where the maximum excitation of a molecule takes place.

The colourless substances also have the property of absorbing certain wavelengths of invisible part of the spectrum. This principle of utilizing the ultraviolet, infrared, and fluorescent methods of analysis used in the detection and measurements of very small quantities of chemical substances is known as spectrophotometry. Absorption curves for most substances enable accurate quantitative and qualitative data to be obtained.

Spectrophotometry is a very useful device for determination of pigments, inorganic compounds (colorimetry), aromatic and heterocyclic organic compounds (ultraviolet spectrophotometry), and even gases (infrared spectrophotometry).

 

Details

Print Book
E-Books
Slices

Format name
PDF
Encrypted
No
Sku
B000000044376
Isbn
9781942270904
File size
16 MB
Printing
Allowed
Copying
Allowed
Read aloud
Allowed
Format name
PDF
Encrypted
No
Printing
Allowed
Copying
Allowed
Read aloud
Allowed
Sku
In metadata
Isbn
In metadata
File size
In metadata