eChapters

Introduction: Indoor Air Pollution

People think that while they are indoors, they are breathing clean air. After all, pollution is found outside, and indoor air is filtered through the HVAC system.

Indoor air can have significantly higher concentrations of pollution than air found outside. Plenty of evidences exists. Global Burden of Disease Risk lists indoor air pollution as the ninth biggest health risk.

7.1. Rural Poverty in Nigeria

The Federal Republic of Nigeria has a population of more than 160 million - the largest in Africa - and a fast-growing economy. Agriculture is the mainstay of the economy, contributing about 40 per cent of GDP. The agriculture sector employs approximately two-thirds of the country’s total labour force and provides a livelihood for about 90 per cent of the rural population. Nigeria is the world’s largest producer of cassava, yam and cowpea - all staple foods in sub-Saharan Africa. It is also a major producer of fish. Yet it is a food-deficit nation and imports large amounts of grain, livestock products and fish. Nigeria’s huge agricultural resource base offers great potential for growth. Recent government policies have started to show results: The agricultural sector reportedly grew by 7 per cent a year between 2003 and 2007, and at a slightly lower rate in recent years. Still, the area of land under cultivation could be doubled. Of an estimated 71 million hectares of arable land, only about half is presently under production. And there is substantial scope for an increase in irrigation, which now covers only 7 per cent of irrigable land. Irrigation and other inputs would substantially increase average yields for major staple crops, which are below those in other developing countries.

Despite Nigeria’s plentiful agricultural resources and oil wealth, poverty is widespread in the country and has increased since the late 1990s. Some 70 per cent of Nigerians live on less than US$1.25 a day. Poverty is especially severe in rural areas, where up to 80 per cent of the population lives below the poverty line, and social services and infrastructure are limited. The country’s poor rural women and men depend on agriculture for food and income. About 90 per cent of Nigeria’s food is produced by small-scale farmers who cultivate small plots of land and depend on rainfall rather than irrigation systems. The poorest groups eke out a subsistence living but often go short of food, particularly during the pre-harvest period. The productivity of the rural population is also hindered by ill health, particularly HIV/AIDS, tuberculosis and malaria.

Climate change is caused by both natural as well as anthropogenic causes and it has been changing since the inception of earth-atmosphere (Figure 2.1). In a broader sense, anthropogenic activities (human activities) also must be considered as natural one in longer time scale as human and their activities are also a part of natural-ecosystem-functions. Among the natural phenomena, volcanic eruptions and continental drifts significantly affect the earth’s precipitation and temperature. A huge volume of CO₂ is released due to volcanic eruption at a little span of time-period which heated up the earth-atmosphere. Climate variability is primarily governed by rise in sea temperature, movement of warm water from the Western Pacific towards Peru, and El Nino which occurs at an intervals of 3-7 years. Climate variability also influenced the alteration in temperature and precipitation world wide. And persistent climate variability cause long term climate change. Therefore, basically three drivers that causes climate change are, the alteration in the energy of sun received by earth-atmosphere (natural causes), variations of ref lectivity of earth-surface- atmosphere system (natural as well as anthropogenic causes) and fluctuations in the greenhouse effect (natural as well as anthropogenic causes).

Plant diseases are classified on the basis of type of pathogenic or nonpathogenic causes of the disease. The classification is based on the plant pathogenic organisms as follows.
1. Parasites
They include both biotic and mesobiotic agents. The diseases are incited by parasites under a set of suitable environment. Association of definite pathogen is essential with each disease.
i. Biotic agents: They are also called as animate causes. They are living organisms.Biotic agents include
1. Prokaryotes
a. True bacteria or bacteria (Facultative parasites) e.g. Citrus canker.
b. Rickettsia-like bacteria (RLB) e.g. Citrus greening, Pierce’s disease of grape.
c. Mollicutes or wall-less prokaryotes
i. Mycoplasma-like organism (MLO) e.g. Sesame phyllody, Egg plant little leaf.
ii. Spiroplasma e.g. Corn stunt, Citrus stubborn.

Introduction
Plant diseases significantly impact agricultural productivity and food security, causing substantial economic losses worldwide. The causes of these diseases can be broadly categorized into inanimate and animate factors, each contributing uniquely to plant health. Understanding these causes is essential for developing effective management strategies to prevent and mitigate disease outbreaks.
A. Inanimate Causes
a) Environmental Factors: Environmental conditions play a crucial role in the development and severity of plant diseases. Key environmental factors include:
• Temperature: Each plant species has an optimal temperature range for growth. Deviations from this range can stress plants, making them more susceptible to pathogens. For example, high temperatures can accelerate the life cycle of some fungal pathogens, while low temperatures can inhibit plant growth, creating conditions conducive to disease.
• Moisture: Water is essential for plant growth, but too much of it can become a problem. High humidity levels and frequent rainfall create an ideal environment for many fungal diseases. Pathogens like Phytophthora and Fusarium thrive under such wet conditions, spreading rapidly in overly moist soils or plant canopies. On the flip side, drought can also lead to trouble. When plants are under water stress, their natural defenses weaken, making them easier targets for both disease-causing organisms (biotic stress) and harmful environmental factors (abiotic stress).

Manifests its action mainly in chronic rheumatic, arthritic and paralytic affections, indicated by the tearing, drawing pains in the muscular and fibrous tissues, with deformities about the joints; progressive loss of muscular strength, tendinous contractures. Broken down senile. In catarrhal affections of the air passages, seems to choose preferably dark - complexioned and rigid fibered persons. Restlessness at night, with tearing pains in joints and bones, and faint - like sinking of strength. This weakness progresses until we have gradually appearing paralysis. Local paralysis, vocal cords, muscles of deglutition, of tongue, eyelids, face, bladder and extremities. Children are slow to walk. The skin of Causticum person is of a dirty white sallow, with warts, especially on the face. Emaciations due to disease, worry etc. Burning, rawness and soreness are characteristic.

Causticum is indicated in the treatment of chronic rheumatism and paralysis accompanying it. Here, Causticum ranks with Rhus Tox and Sulphur.

Key words : CAVD, Drug Design, Bioinformatics, CADD, Co-factor, Vaccinology, infectious diseases, Jenner, immunity, Molecular modeling, Immunoinformatics, Antigen, Antibody, Live Vaccine, Alive Vaccine, Protein-peptide, Enzyme, Tools for Vaccine design,
 
Vaccine – Prevention is Better than Cure

A vaccine is a biological preparation that improves immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing microorganism, and is often made from weakened or killed forms of the microbe, its toxins or one of its surface proteins. The agent stimulates the body’s immune system to recognize the agent

1. Introduction
Animal experimentation remains a cornerstone of scientific research in many fields, from medical advances to pharmaceutical testing. However, the ethical treatment of laboratory animals has become a point of significant concern worldwide. India, through the Committee for the Control and Supervision of Experiments on Animals (CCSEA), ensures that ethical standards are maintained in research institutions. Established under the Ministry of Environment, Forests, and Climate Change (MoEF&CC), CCSEA is tasked with overseeing the use of animals in experiments, ensuring that procedures adhere to ethical guidelines and international norms. CCSEA’s guidelines are in line with international standards set forth by organizations such as the International Council for Laboratory Animal Science (ICLAS) and the European Union (EU), but they are tailored to address local needs and conditions. The guidelines, which focus on the welfare of laboratory animals, emphasize the ethical review process, animal care, and the importance of minimizing animal suffering. They also stress the need for researchers to implement the 3Rs—Replacement, Reduction, and Refinement—to minimize the use of animals and ensure humane practices in research. This chapter explores the CCSEA guidelines in detail and compares them with animal welfare regulations from around the world, including the United States, European Union, Japan, and Australia. By understanding the similarities and differences between these regulations, researchers and policymakers can ensure the ethical treatment of laboratory animals on a global scale.
2. Objectives of CCSEA Guidelines
The main objective of the CCSEA guidelines is to ensure that laboratory animals are treated ethically and humanely while also supporting the validity and scientific rigor of research. The guidelines encourage researchers to prioritize animal welfare while minimizing unnecessary suffering. Specifically, CCSEA focuses on:
1. Ethical Treatment of Animals: Ensuring that animals are housed in suitable conditions, given adequate veterinary care, and provided with a comfortable environment to reduce stress.
2. Justification of Animal Use: Ensuring that animals are used only when necessary, and that their use is scientifically justified.
3. Pain and Stress Minimization: Ensuring that experimental procedures cause the least pain, distress and suffering possible.

1.1 Policy Background

Human activities have resulted in the alteration of the composition of our atmosphere triggering change in the Earth’s climate. The world’s population has grown at an alarming rate with a corresponding increase in demand for natural resources, energy, food, and goods. As a consequence of increase in consumption, vast quantities of gases and effluents are discharged that change the composition of the atmosphere and its capacity to regulate its temperature. The rise in the global temperature is caused by the accumulation of the so-called “greenhouse gases”, namely, carbon dioxide (CO₂), methane, nitrous oxide, and chlorofluorocarbons. Energy received from the sun is absorbed as short wavelength radiation and is eventually returned to space as long wavelength infrared radiation. Greenhouse gases absorb the infrared radiation, trapping it in the atmosphere in the form of heat energy.

Objective: To synthesize cDNA from isolated plant total RNA.

Background information:

Complementary DNA (cDNA) is double-stranded DNA made from template of single stranded RNA, [e.g., mRNA or microRNA] by reverse transcriptase enzyme. Mostly cDNA is used for cloning of eukaryotic genes in the prokaryotes. For the expression of a specific protein in a cell where the expression of that protein is not found (i.e., heterologous expression), the cDNA will be transferred that codes for the protein to the recipient cells. Retroviruses (e.g. HIV-1, HIV-2, simian immunodeficiency virus, etc.) also produce cDNA naturally and integrate in host's genome and further creates provirus (Croy, 1998). Major use of cDNA is in gene cloning or as gene probes or in the creation of a cDNA library. When scientists transfer a gene from one cell into another cell for the expression of new genetic material as a protein in the recipient cell, the cDNA will be added to the recipient (rather than the entire gene), because the DNA for an entire gene may have certain DNA that may not code for the protein or that interrupts the coding sequences of the protein (e.g., introns). Partial sequences of cDNAs are often obtained as expressed sequence tags.

Dr. Chauhan is an exceptional individual who had achieved a significant milestone in his academic and professional journey. Completing a Bachelor of Science (Honours) with an impressive 80.3%, Dr. Chauhan’s accomplishment is a reflection of his hard work, dedication, and unyielding passion for the field of veterinary science. This remarkable achievement not only underscores his
academic brilliance but also cements his position as an inspiring figure in the veterinary community.
From an early age, Dr. Chauhan demonstrated an innate love for animals and a deep sense of responsibility toward their well-being. These qualities formed the foundation of his journey in veterinary science. His BVSc&AH (Honours) degree, completed with such distinction, is not just a testament to his intellectual capabilities but also to his tireless commitment to improving animal health and welfare. Pursuing a degree in Veterinary science is no small feat. It demands a unique combination of scientific expertise, practical skills, and emotional resilience. For Dr. Chauhan, the rigorous academic journey involved mastering a wide array of subjects, including animal Anatomy, Physiology, Pathology, Pharmacology, and Microbiology. Each subject posed its own set of challenges, yet he tackled them with unwavering determination and an insatiable thirst for knowledge. His exemplary performance, as evidenced by his impressive score of 80.3%, highlights his ability to excel even under pressure. What sets Dr. Chauhan apart is not just his academic excellence but also his holistic approach to learning. Beyond textbooks and lectures, he actively sought opportunities to gain hands-on experience, volunteering at animal shelters and participating in community outreach programs. These experiences not only enriched his understanding of animal care but also shaped his perspective as a compassionate and empathetic veterinary professional.

Introduction

Seasonality in agriculture is a major determinant of poverty, food insecurity and hunger in areas having harvest only once or twice a year. Undiversified livelihoods survive on the crops that the households consume as food and sell for income. The risk being high, a single failed harvest can cause huge losses and can destitute a marginalized household with limited or no savings, increasing their dependence on borrowings leading to indebtedness later on. Punjab being one of the pioneer states in green revolution in country is facing lot of challenges due to monoculture i.e. paddy-wheat as the major crop rotation followed on 92% area of the state. The situation has led to serious repercussions in agriculture sector of the state along with social, financial, and ecological issues. 

Introduction 
It is a common vegetable crop of rabi season which belongs to the family Apiaceae (Umbelliferae). Due to prevalence of protandry condition, the crop is cross pollinated in nature and self-pollination within individual flower is restricted. It comprised of three distinct cultivated varieties grown over the world for various economic purposes and classified as below depending upon usefulness of different parts.
Origin
It found is globally distributed in New Zealand, Australia, South Africa, Mediterranean basin, and South America, whereas Argentina and Chile are the richest sources. Habitat is extensively ranging from Egypt, Algeria, and Abyssinia to Sweden.

Celery was grown as an aromatic and therapeutic herb by Egyptians, Greeks, and Romans. It was first grown in Italy in the 16th century after this wild variety. It was then introduced to the British Islands by the Italians and French at the end of the 17th century. It was first grown in North America in the nineteenth century. Celery’s young leaves and stem are high in minerals, vitamins, and proteins, making it one of the most essential therapeutic plants. Celery oil has a pleasant aroma. This aromatic oil aids in the efficient functioning of the human brain. On an area of roughly 5000 acres, the crop is grown primarily in Punjab (Jallandhar, Gurdaspur, and Amritsar districts), Haryana, and western Uttar Pradesh (Ladhwa and Saharanpur districts). Punjab provides almost 90% of the overall production

English name : Celery
Botanical name : Apium graveolens L.
Family : Apiaceae
Chromosome number : 2n = 22
Centre of origin : Italy
Celery is botanically known as Apium graveolens L. and is commercially recognized by different names in India, like Karnauli, Ajmod, or garden celery. There are four horticultural varieties of celery. Apium graveolens var. dulce (Miller) Pers. is cultivated for its edible leaves and stalks, commonly used in salads, appetizers, and soups. Another variety, var. rapaceum (Mill) Gaudich, known as celeriac, comprises dark green leaves grown for its root tubers, which are cooked and consumed. The other two varieties are var. secalinum and smallage.
In India, the main variety cultivated is var. dulce. Celery is commercially available in various forms, including seeds, flakes, as a vegetable, celery seed oil, and oleoresin. Celery seeds have specific quality characteristics viz. moisture content ranges from 5-11%, volatile oil content from 1.5-3% (average 2.4%), non-volatile ether extract from 5.8-14.2% (average 9.4%), cold water extract from 5.9-12.6% (average 8.4%), total ash from 6.9-11.0% (average 8.8%), and ash insoluble in acid from 0.5-4.0% (average 2.5%).

The cell number of a particular cell type in a total cell population might indicate the physiological or pathological status of the cell smear/FNAC/tissue. ImageJ is a powerful open- source software extensively used for image assessment, including cell counting. In this chapter, the steps to count cells using ImageJ has been discussed. There are two ways to count the cells in a research image using ImageJ.
A. Manual Counting
Use the “Cell Counter” plugin or simply use the multipoint tool in ImageJ. Open it, select the cell type you want to count, and click on each cell in the image to tally them. Double-click on the multipoint tool. A separate window will open named point tool. One can select the type of marking, color and size of making (Figure 30). Keep clicking on the cell type to be counted. It will record the number of cells counted. If one wants to count the second cell type in the same image, change the counter number and select the size, color and type of click point.

A finite growth capacity is a characteristic of all cells derived form the normal animal tissue. The cells pass through a series of age related changes before being incapable to divide further. The finite number of generations of growth is a characteristic of the cell type, age and species of origin and referred to as the “Hayflick limit”. The cells derived from embryonic tissue have a greater growth capacity than those derived from adult tissue.

Introduction

Cell culture is a technique that involves the isolation and in vitro maintenance of cells isolated from tissues or whole organs derived from animals, microbes or plants. This technique has immeasurable role in the field of biology. The scientific progress in biology, microbiology and biotechnology in recent years can be credited on the development of cell culture technology. With the development of cell culture the isolation of viruses has become less cumbersome, the assessment of the efficacy and toxicity of new drugs has been easier, new vaccines are being developed and there has been development in biotechnology assisted reproductive technology.

In general, animal cells have more complex nutritional requirements and usually need more stringent conditions for growth and maintenance. For the growth of the cell in vitro specific mediums are required by the cells. Previously natural mediums like plasma ,serums were used but with the advent of synthetic media the specific needs of different cell types can be catered with. Cell culture is governed by a provided set of protocols requiring a sterile pure culture of cells, various nutrients for its growth, sterile cell culture hood, appropriate aseptic techniques and the utilisation of suitable conditions for optimal viable growth of cells.

Plant cell culture
Introduction

As the human population is expanding there has been increasing concern over whether current rates of food productions can support the growing population. In response to the increasing demand, scientists and farmers have been working hard to come up with new ideas to meet these needs. These ideas range from simple procedures including selection of the best seeds to more complex procedures requiring the transplantation of genes into different plant species. This chapter focuses on one of the important aspects of plant science which is the growth of plant cells in an artificial media. This process is known as plant cell culture and can be applied in many different ways. 

Introduction
It is a fundamental biological process in which one cell splits into two or more daughter cells. Both unicellular and multicellular organisms rely heavily on it for growth, development, repair, and reproduction. There are two main types of cell division: mitosis and meiosis. Mitosis occurs in somatic cells and produces two genetically identical daughter cells that share the same chromosomal number as the parent cell. This process is necessary for tissue development and repair. Meiosis, on the other hand, happens in germ cells and results in the formation of gametes, which reduces the number of chromosomes by half to ensure genetic diversity in progeny. Proper regulation of cell division is vital for maintaining cellular health, and disruptions in this process can lead to disorders like cancer.
The different stages of cell division is as follows:-
1. Interphase
• Although not a component of mitosis, interphase is essential for preparing the cell for division. It is separated into three sub-phases:
• G1 phase (Gap 1): The cell expands in size while creating proteins and organelles. S phase (Synthesis): DNA replication occurs, guaranteeing that each daughter cell receives an identical copy of the genetic information.
• G2 phase (Gap 2): The cell continues to expand while new organelles are synthesised)
The cell checks for DNA replication mistakes and gets ready for mitosis.
2. Prophase
• In this phase chromatin condenses into visible chromosomes, each made up of two sister chromatids linked at the centromere.
• The nuclear membrane breaks down, allowing the spindle fibres to interact with the chromosomes.

There are a number of different cell lines derived from human and animals. With the dramatic increase in numbers of cell lines, the risk of intraspecies and interspecies cross contamination rises proportionally. It is particularly a major problem in laboratories where many different cell lines of human and animal origin are handled at a time. The purity of the primary cell or continuous cell lines and species of its origin should be checked on a regular basis to authenticate the cell line identity. In the absence of such monitoring, inter and intra species cell line contamination are likely to occur in the laboratory resulting in loss of investigator’s time effort and resources. The advantages of working with a well defined cell line free from contaminating organisms would appear obvious.

Cell Lysis Procedure

Pellet the cells in a microfuge tube: add 1.5 ml culture, centrifuge for 15 seconds at maximum speed, discard the supernatant, and then repeat the procedure. This will result in the cells from 3 ml of culture in a single tube.

Resuspend the cells in 1 ml Lysis buffer.

Take 300 µl aliquot for Bradford protein assay.

Add 50 µl lysozyme, and mix gently.

After 10-20 minutes at room temperature, microfuge for 10 minutes to pellet cell debris.

Use supernatant for LDH assay.

Plant body consists of numerous microscopic box like components called cells. The word cell has been derived from the Latin word cellula, meaning a small room. The descriptive term for this smallest living biological structure was coined by Robert Hooke in a book he published in 1665. When he compared the cork cells, he saw through his microscope to the small rooms monks lived in. The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life, which is classified as a living thing and is often called the building block of life (Maton et al., 1997). It is defined as a mass of protoplasm surrounded by a membrane- the plasma membrane- within which complicated chemical reactions are going on.

ALL LIVING ORGANISMS ARE MADE UP OF UNITS CALLED CELLS

All living creatures are made from 1 or more cells

All cells are produced from previously existing cells (no spontaneous generation)

All cells appear to be descended from the first cell which existed about 4 billion years ago

For a species to exist its reproductive cells must be potentially immortal (no aging)

Our bodies start from a single cell and contain about 100,000,000,000,000 (10^14) cells at maturity

Principle

Cell viability refers to the quantity of healthy cells in a sample, while cell proliferation is a crucial indicator for comprehending the mechanisms and pathways involved in the survival of cells or death following exposure to toxic substances. The methods used to assess viability are typically the same as those used to detect cell proliferation. Cell cytotoxicity and proliferation assays are commonly employed in drug evaluations to determine if the test compounds impact cell proliferation or exhibit direct cytotoxic effects. Cell viability can be determined by calculating the ratio of total live cells to the total number of cells (live and dead). Staining also helps to observe the general cell structure. Cell proliferation assay by MTT. Metabolically active cells reduce the yellow tetrazolium MTT (3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide) through dehydrogenase enzymes to produce NADH and NADPH. The purple formazan produced inside the cell can be dissolved and measured using spectrophotometry. The MTT Cell Proliferation Assay quantifies cell proliferation rate and detects decreases in cell viability caused by metabolic events leading to apoptosis or necrosis. The MTT Reagent produces minimal absorbance values when no cells are present.

I. WALL COMPONENTS – CHEMISTRY

The main ingredient in cell walls are polysaccharides (or complex carbohydrates or complex sugars) which are built from monosaccharides (or simple sugars). Eleven sugars are common in these polysaccharides including like glucose and galactose. Carbohydrates are good building blocks because they can produce a nearly infinite variety of structures. There are a variety of other components in the wall including protein, and lignin. Let’s look at these wall components in more detail:

A. Cellulose: β1,4-glucan (structure provided in class). Made of as many as 25,000 individual glucose molecules. Every other molecule (called residues) is “upside down”. Cellobiose (glucose-glucose disaccharide) is the basic building block. Cellulose readily forms hydrogen bonds with itself (intra-molecular H-bonds) and with other cellulose chains (inter-molecular H-bonds). A cellulose chain will form hydrogen bonds with about 36 other chains to yield a microfibril. This is somewhat analogous to the formation of a thick rope from thin fibers. Microfibrils are 5-12 nm wide and give the wall strength - they have a tensile strength equivalent to steel. Some regions of the microfibrils are highly crystalline while others are more “amorphous”.

Summary

Multicellular organisms are made up of diverse set of cells. Cells respond to the changes in the particular microenvironment by means of cellular communication. This cell-cell communication is extremely important for the development, maintenance and survival of the organism. This communication is equally important for the unicellular organisms. Cells communicate to one another and respond to the environmental changes using diverse chemical languages, as discussed in this chapter. However, in many cases like multicellular organisms, cell communication is primarily mediated by specific receptor(s) expressed on the cell membranes. These receptors bind to the extracellular signaling molecules (called ligands) and activate specific signaling pathways to bring about particular cellular responses. These different receptors, ligands and signaling pathways are briefly discussed here.

Cell mediated immune response (CMI) is the major defense mechanism against intracellular microbes and tumor cells. It is mediated mainly by T lymphocytes. T cells originate in bone marrow but the maturation of T cells occurs in thymus.

Cell mediated immune response performs different functions in protecting the immune system. When antigens are destroyed by cells, without producing antibodies, the immunity is called cell-mediated immunity (CMI) or cellular immunity. In this immunity T cells play a major role. The principal role of cell mediated immunity is to detect and eliminate the cells that have intracellular pathogens. When the antigen remains inside the cell the antibody cannot handle them. The intracellular pathogens are controlled by cell- mediated immunity. CMI is invited by the recognition of antigens by T cells. T cell lymphocytes recognize protein antigens of intracellular microbes that are displayed on the cell surface of infected cells. It is also important for elimination of cells which express foreign MHC molecules. Antigen specific and nonspecific cells can contribute to the cell-mediated immune response. The activities of both specific and non-specific components usually depend on effective local concentration of cytokines.

Cell

Cells (small, membrane-bounded structures filled with a variety of chemicals in an aqueous solution that interact to give life) are the basic unit of life. Cells are capable of acquisition and use of energy, have the capacity to reproduce and respond to the environment and are able to carry out a variety of chemical reactions. They maintain a relatively constant internal environment despite changes in the external environment. There are two types of cells, namely, prokaryotes and eukaryotes.

The prokaryotic (pro = before, karyote = nucleus) cells are the simple form of cell types which include the various types of cells of bacteria and their relatives, all belonging to kingdom Monera. They possess a cell wall constructed of peptidoglycan, a substance unique to prokaryotes. Beneath the cell wall, there is a plasma membrane that encloses a cytoplasm containing DNA, RNA, proteins and various small molecules.

This chapter describes the cells, tissues and organs responsible for immune defence. It examines lymphocytes, macrophages, dendritic cells, neutrophils, mast cells, natural killer cells and plasma cells, emphasizing their respective functions. Primary and secondary lymphoid organs—including bone marrow, thymus, bursa of Fabricius, spleen, lymph nodes and mucosa-associated lymphoid tissue—are discussed. The chapter also covers lymphocyte maturation, antigen presentation, phagocytosis, immune-cell surface markers and the organization of lymph-node regions. Positive and negative selection of T lymphocytes and the formation of memory cells are included. Together, these topics explain how immune components develop, communicate and coordinate effective responses against infectious agents.

Cells are the Working Units of Life

With the possible exception of viruses, every form of life on Earth either is a cell or composed of cells. All cells come into existence through the activity of other cells.

All Cells are either Prokaryotic or Eukaryotic

All cells can be classified as prokaryotic or eukaryotic. All plants, animals, fungi, and protists are either single eukaryotic cells or are composed of eukaryotic cells. Prokaryotic cells are either bacteria or archaea. Eukaryotic cells have most of their DNA contained in a membrane-lined nucleus, whereas prokaryotic cells do not have a nucleus. Eukaryotic cells also have more specialized structures, called organelles, than do prokaryotic cells. All prokaryotes are single-celled, whereas many eukaryotes are multi-celled.

The Eukaryotic Cell

There are five principal components to the eukaryotic animal cell: the nucleus, other organelles, the cytosol, the cytoskeleton, and the plasma membrane. Organelles are “tiny organs” within the cell that carry out specialized functions, such as energy transfer and material recycling. The cytosol is the fluid in which these organelles are immersed (The cytoplasm is the region of the cell inside the plasma membrane but outside the nucleus.) The cytoskeleton is composed of several groups of proteins that give the cell support and facilitate transportation of cellular elements. The plasma membrane is the chemically active outer boundary of the animal cell. Plant cells have a plasma membrane that has, outside of it, a cell wall.

Introduction

Robert Brown discovered the nucleus in some plant cells in 1831. After analyzing tissues from a range of animals and plants, T. Schwann (1839) declared, “All living organisms are composed of cells.”

The fundamental elements of Prokaryotic and Eukaryotic cells

The simplest cells, called prokaryotic cells, have a straightforward structural arrangement. There is only one membrane system in it. They contain rickettsia, spirochete, mycoplasma, virus, blue-green algae, and bacteriablue-green algae, or cyanobacteria are the largest and most intricate prokaryotes, where higher plant photosynthesis occurs and have changed throughout time.

Prokaryotic cells

Prokaryotic cells range in size from 1 to 10 µm. They take place in a range of formats. A bacterial cell is made up of three basic parts:

I. External layer: It is composed of the inner cell or plasma membrane, middle cell wall and outer slimy capsule.

a. Cell membrane: The thin, flexible membrane of the cell, composed of proteins and lipids, regulates the flow of chemicals throughout the cell. It carries respiratory enzymes for reactions that release energy. Respiratory enzymes are found in mesosomes, which are folded regions of the plasma membrane that are compared to the mitochondria in eukaryotic cells. Similarly, the pigments and enzyme molecules found in photosynthetic cells are linked to the in-folds of the plasma membrane known as photosynthetic lamella, which is responsible for absorbing light and converting it into chemical energy.

b. The cell wall: It is the non-living, semi-rigid layer that encloses the cell membrane, with a thickness that varies from 1.5 to 100 µm. It is chemically made up of peptidoglycans. Certain bacteria, such as mycoplasma, don’t have cell walls.

A cellular phone is also known as a mobile phone, cell phone, portable phone and a hand phone. It is a device that can make and receive telephone calls over a radio link while moving around a wide geographic area. It does so by connecting to a cellular network provided by a mobile phone operator, allowing access to the public telephone network.

The cell phone was invented by Dr. Martin Cooper who led a team of developers at Motorola and made the first cell phone call in April 3, 1973 at Motorola.

Today, cell phones are becoming capable of doing almost anything a computer is capable to do. Below, are few examples of what a phone can do?

Introduction
Embryogenesis begins with the fertilization of the oocyte by the sperm, leading to the formation of a zygote. This single cell undergoes a series of highly regulated mitotic divisions known as cleavage, forming a multicellular structure called the blastocyst. As the blastocyst implants in the uterine wall, the cells continue to divide and differentiate into the three primary germ layers: the ectoderm, mesoderm, and endoderm. Each of these layers gives rise to specific tissues and organs, controlled by genetic instructions and cellular signalling mechanisms.One of the most critical aspects of embryogenesis is the intricate interplay of cellular signalling pathways and genetic mechanisms, which regulate the precise growth and differentiation of cells into tissues and organs. Understanding these mechanisms not only helps in comprehending normal embryonic development but also in diagnosing and treating developmental disorders in veterinary practice.
Cellular Signalling in Embryonic Development
Cellular signalling is a fundamental process in embryogenesis that ensures cells communicate with each other to perform specific tasks. The coordination of cell proliferation, differentiation, migration, and apoptosis (programmed cell death) is essential for the proper formation of tissues and organs.
Types of cell signalling
1. Short range signalling: It involves communication within a cell as well as between nearby cells. This includes:
a) Paracrine signalling: where a cell releases signals that affect neighbouring cells.
b) Autocrine signalling: where a cell sends signals to itself, affecting its own behaviour.

Introduction

The smallest, most basic, most primitive organisms are known as prokaryotic (Greek: pro= primitive or prior, and karyon = nucleus). Likely, they originated around 3.5 billion years ago. Bacteria, such as Mycoplasma and Cyanobacteria, are known to contain these cells. A prokaryotic cell is a deeply organized single-enveloped system. Its constituent nuclear parts are encased in a plasma membrane, with the cytoplasmic ground substance encircling the center. Prokaryotic cells’ cytoplasm lacks distinct cytoplasmic organelles, the nuclear envelope, and any other cytoplasmic membrane.

Despite being incredibly thin and delicate structures, in Eukaryotes plasma membranes are essential to many of a cell’s most vital processes. Membranes are lipid-protein assemblages where non-covalent linkages hold the constituents in place in a thin sheet. Both integral protein and phospholipid lateral mobility are significantly impacted by the physical condition of the lipid bilayer. The plasma membrane is a selectively permeable barrier that permits solute passage via assisted diffusion, active transport, and simple diffusion via membrane channels or the lipid bilayer. A system of membrane organelles, such as the endoplasmic reticulum, Golgi complex, and lysosomes, is found in the cytoplasm of eukaryotic cells. These organelles are physically and functionally connected to the plasma membrane and one another. The cytoplasm is separated into a luminal region inside the ER membranes and a cytosolic space outside the membranes by the endoplasmic reticulum (ER), a network of tubules, cisternae, and vesicles. Additionally, the ER is where the majority of a cell’s membrane lipids are generated and transported to different locations. Proteins’ asparagine residues are added with sugars (a process known as glycosylation), which starts in the rough ER and continues in the Golgi complex.

Estimation of Cellulose in Feeds and Fodders
Principle

The feed well ground is digested with acetic acid which dissolves all other constituents like protein, disaccharides, fatty acids, etc., and cellulose and mineral contents are unaffected. The residue is made acid and alcohol free by washings. Alcohol removes water, benzene removes pigments and fat and at the end the sample is dried and ashed. The difference between the dried weight before ashing and weight after ashing gives cellulose content of the feed sample.

Introduction 
The world is reaching a crucial moment in the energy sector as the third decade of the twenty-first century unfolds (Azarpour et al., 2022). Concern over the prospects of our energy supplies has increased globally because of the key priorities posed by climate change and the necessity for economic stability and energy security. The transition to energy from renewable sources is widely viewed as a crucial component in transforming our relationship with nature, the economy, and cultural values (O'Connor and Cleveland, 2014; Hassan et al., 2024). Reducing the usage of fossil fuels in our energy supply systems is known as an energy transition (Cherp, Jewell and Goldthau, 2011). Fossil fuels, such as crude oil, and natural gas, supply a substantial share of the world's energy. Interest in energy transitions has grown because, in addition to the fact that most fossilfuel resources are reserve-based, burning the vast amounts of fossil fuels that are currently available, and the resulting environmental effects are the main drivers of energy transitions (Crow, Brown and De Young, 2006). Bioenergy refers to renewable energy produced from materials derived from biological sources. Any organic substance such as plants, agricultural or forestry residues, or the organic portion of industrial and municipal trash that stores solar energy as chemical energy is considered a biomass feedstock. The first energy source that humans employed was biomass, which could supply roughly onefourth of the world's primary energy, or 138 EJ (exajoules) (calculated by averaging estimated numbers from five reports) (Welfle, 2017). Because of its versatility in producing various forms of energy and chemicals, bioenergy is a desirable energy choice for all stages of development. It has a great potential for integration with current infrastructures, may produce energy that may be dispatched to balance changing demands, and most importantly provides energy with lower greenhouse gas emissions compared to fossil fuel pathways, unlike many other renewable energy sources (Demirbas, 2008). It is anticipated that sustainable renewable energy sources, including biomass, sun (heat energy and PV (photovoltaic)), wind, hydroelectricity, geothermal, and wave and tidal energy sources, are expected to play a vital role in the future global energy supply (Panwar, Kaushik and Kothari, 2011). Compared to other sources of sustainable and clean energy, biological feedstock offers the advantage of being able to be stored and being easily accessible year-round from a variety of sources. Estimates suggest that biomass contributed 10% of the global energy demand in 2008 (Main-Knorn et al., 2013), with further advancements expected to increase this contribution by two to six times by 2050 (Zema et al., 2012). It is believed that biomass is a distinctive and promising form of "green" energy. It is abundantly found in nature and can be easily produced in most rural environments (Broda, Yelle and Serwanska, 2022). Biomass sources are generally classified into two categories: inherent and processed materials, the most common forms of sources comprise, wood, logging wastes, animal dung, aquatic plants and algae, agricultural crop waste products and processing residues, and municipal solid waste. Additionally, three categories have been established for biomass resources. Wastes include agricultural remnants, agricultural processing by-products and wastes, urban wood debris, urban organic materials, and wastes from mills. Forest goods include bark, sawdust, logging leftovers, timber, trees, plants, and wood debris from land clearing. Bioenergy crops encompass grasses, fast-growing woody plants, woody herbaceous plants, oilseed plants (soybean, sunflower, and safflower), sugar crops (cane and beet), and starch plants (corn, wheat, and barley) (Qian, Malmali and Wickramasinghe, 2016). Growers favour energy plants, sometimes referred to as

Cellulosic ethanol refers to the production of ethanol, an alcohol fuel, from cellulose found in plant fibers rather than from seeds or fruits. This biofuel can be derived from various sources such as grasses, wood, and other plants. The fibrous components of these plants are mostly from crop residues and other sources indigestible for animals, except for ruminants like cows and sheep, as well as hindgut fermenters like horses, rabbits, and rhinos. The interest in cellulosic ethanol stems from its potential economic value. Plant growth and cellulose formation serve as a mechanism to capture and store solar energy in a chemically stable manner, facilitating easy transport and storage of the resulting supplies. Moreover, the ability of grasses and trees to grow in temperate regions makes cellulosic ethanol commercially viable and offers a potential solution from non-food sources other than grain and tuber starch. This cellulosic ethanol development in the biofuel industry presents an opportunity to derive carbonaceous liquid fuels and petrochemicals, which are vital for our current standard of living, in a balanced and renewable manner by recycling carbon from the surface and atmosphere through any kind of plant orgin or any plant or tree species, Additionally, commercially viable cellulosic ethanol could mitigate the issue associated with conventional biofuels based on grains, which compete with food production and may lead to increased food prices. However, the production of cellulosic ethanol is currently economically feasible and has been implemented on a large scale in India. Several 2G ethanol plants are being developed by companies like Indian Oil Corporation Limited (IOCL), Bharat Petroleum Corporation Limited (BPCL) and Hindustan Petroleum Corporation Limited (HPCL). Different types of biomass contain varying amounts of sugars, and the complexity of the biomass is determined by the structural and carbohydrate components. Plant biomass mainly consists of lignin (13.6-28.1%), cellulose (40.6-51.2%) and hemicellulose (28.5-37.2%), which serve as the raw materials for fuel production. The conversion of biomass into sugars is a crucial step in biofuel production. Therefore, selecting an appropriate pretreatment process based on the biomass type is essential to achieve optimal sugar yield with minimal energy input.

Celosia is an attractive flowering crop valued for its distinctive inflorescences, bright colours and use as loose and ornamental flowers. The crop includes forms such as Cristata, Plumosa and Spicata, with the characteristic brain-like appearance of cockscomb resulting from fasciation. This chapter deals with the origin, distribution, genetics, botanical features and important varieties of Celosia. It explains climatic and soil requirements, propagation, land preparation, nutrient management, planting, irrigation and cultural practices for commercial production. The chapter also covers plant growth regulation, insect pests and diseases, harvesting, postharvest management and yield. Its practical approach makes it relevant to students, growers and floriculture entrepreneurs.

Scientific name: Centella asiatica (L) Urban
Fmily: Apiaceae
The plant Centella asiatica belongs to the family Apiaceae. C. asiatica widely distributed throughout tropical and subtropical regions of the world. Commonly known as Gotu Kola, Indian pennywort or Asiatic pennywort. It has a long history of utilization in Chinese and Ayurvedic traditional medicines since centuries. Leaves are yellowish-green color, thin and edible. The plant
grows horizontally through its stolones which roots in underground. C. asiatica shows a wide range of biological activities such as anti-inflammatory, anti-ulcer, wound healing, anti-psoriatic, anti-convulsant, hepato protective, immuno-stimulant, anti-diabetic, sedative, anti-bacterial, anti-viral, antitumor, cardio protective and anti-oxidant activities.
Origin and distribution
C. asiatica widely distributed throughout tropical and subtropical regions of the world. C. asiatica is widely found in Sree Lanka, India, Indonesi, Malaeysia and China. It is especially common in the Indian sub continent. It is also present in Eastern and Northern parts of Australia. It may also found in Tropical parts of Africa and Madagascar. C. asiatica has been introduced and is now cultivated or found in Thailand, Cambodia, Vietnam, The Philippines, Myanmar, and Brazil. Beyond Madagascar it is found in parts of Southern and Central Africa. The plant grows in countries such as Hawaii and Fiji. It is also found in Southern states like Florida.

Centre of origin are also known as centre of diversity. N. I. Vavilov in 1926 has proposed that crop plants evolved from wild species in the areas showing diversity and termed them as primary centers of origin. Primary centers, crops moved to other areas with the movements of man. But in some areas, certain crop species show considerable diversity of forms although they did not originate there. Such areas are known as secondary centers of origin of these species. Genetic diversity is essential for crop improvement. Vavilov has suggested eight main centers of origin of crop plants.

1. Chinese Centre

This centre is considered to be one of the earliest and largest independent center of origin of cultivated plants. This centre includes mountain regions of central and western China. The endemic species listed from this centre include, soya bean, radish, turnip, pear, peach, plum, colocasia, buckwheat, opium poppy, brinjal, apricots, oranges, china tea etc.

2. Himalayan Centre

This centre is also known as the Indian centre of origin. This centre includes regions of Assam, Burma, Indo-china and Malayan Archipelago. The crops originated from this centre are rice, red gram, chick pea, pea, mung, brinjal, cucumber, sugar cane, black pepper, moth bean, rice bean, cotton, turmeric, indigo, millets etc.

Centesis is a surgical puncture or perforation into body cavity or structure usually done to aspirate fluid, air or tissue. The medical purpose of puncturing body cavities is not only to obtain fluid sample for diagnostic purpose but also to remove excessive fluid for therapeutic purpose for alleviating the respiratory distress owing to excessive fluid accumulation in peritoneal cavity, pleural cavity or pericardial sac. This procedure is usually done to get fluid from abdominal cavity, thoracic cavity, pericardial sac or joint capsule and is aptly known as abdominocentesis, thoracentesis, pericardiocentesis or arthrocentesis respectively.

Brain

The brain, a command centre of the body, is a complex organ. The substance of the brain is made of the grey matter and the white matter. The grey matter is often identified as cerebral cortex but other parts of the brain also contain the grey matter. Inside the brain, the grey matter is organized into large accumulations of neurons which are called the nuclei of the brain. Each nucleus is associated with a specific function. In addition to neurons, there is other type of cells the glial cells called neuroglia. The neurons are responsible for sending and receiving impulses or signals. The glial cells are nonneuronal and provide support and nutrition to neuronal cells, form myelin and facilitate signal transmission in the nervous system. The white matter is made of millions of nerve fibres that are coming from neurons and are going to establish communications with different parts of the brain and spinal cord. Since these nerve fibres are coated with myelin sheath around them these appear white and the area occupied by these nerve fibres become the white matter of the brain.

The brain has three basic components, the forebrain, midbrain and the hindbrain.

Fore brain: The forebrain (Prosencephalon) is the rostral portion of the brain. It consists of cerebrum (Telencephalon) and the thalamus, hypothalamus and pineal gland together constituting the interbrain (Diencephalon).

Mid brain: The midbrain (Mesencephalon) is the middle portion of the brain. It is in the centre lying between the interbrain and hindbrain. It consists of a cranial part of brain stem.

Hind brain: The hindbrain (Rhombencephalon) is the caudal most portion of the brain. It consists of remaining (caudal) part of the brain stem, the medulla oblongata (Myelencephalon) and the cerebellum and pons (Metencephalon).

The place of origin of the crop plant can be found out on the basis of genetic affinities. This would mean to find out the geographical distribution of the wild progenitors of the cultivated plants. If one can locate the distribution of a given progenitor, one can delimit the area in which domestication could have occurred. Vavilov based his judgment on variation patterns in cultivated plants. Information on wild plants in those days was much more fragmentary than what it is today. Even today, genetic and ecological information on wild relatives of several cultivated plants is incomplete and in such cases assessment of a place of origin is difficult to make. However, in most cases required information is available on genetic affinities between wild and tame, on distribution areas and on ecological affinities of the wild progenitors. On this basis it is possible to determine the initial place of origin.

Since historical times, Indian spices have been contributed not only to the country’s wealth and prosperity but also to the subcontinent itself as a whole. Spices precisely witnessed many wars, bloodshed, armoury alongwith the glowing accounts and adventurous voyage by Pliny, Ptolemy, Marco Polo, Vasco da Gamma and other travelers. The Southern parts of India, especially the Malabar Coast, with its abundance of the World’s best pepper, cinnamon and ginger was enormously creating impact of a plethora of spices which attracted the foreign trade and continue even today by creating a unique brand value globally. In the past, invaders travelled to India by overcoming many odds and barriers with the prime focus on capturing spice trade and dominating the trade scenario of those days throughout the world. As a result, gradually Indian spices travelled far and wide to traditional destinations by providing flavor, aroma, pungency, taste and colour to a variety of foods and beverages.

It was the end of 18^th century, from when scientific research began on the idea of origin of cultivated plants. The pioneers of this field were Darwin, Alphonse de Candolle, N.I Vavilov and many more. Charles Darwin wrote his famous book ‘On the Origin of Species by Means of Natural Selection’, or the ‘Preservation of Favoured Races in the Struggle for Life’ published on 24^th November 1859. According to him, cultivated plants may have originated from its wild form after a series of intense modifications. Afterwards, a Swiss botanist Alphonse de Candolle studied 247 cultivated plant species and documented his work in the book “Origin of cultivated plants” in 1886. Later, Vavilov first identified the Centres of origin. He could determine the origin of plants by analyzing the pattern of variation and proposed that, crop plants have been evolved from their wild species in the geographic region of the greatest genetic diversity of that particular plant. That area is known as the primary centres of origin of the particular plant. But, some crop species were found to show substantial genetic diversity even though they did not originate there. Such areas are known as secondary centres of origin for that particular species.