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- Biotechnology
- Terms And Explanations
- 7. Texts in the natural sciences in english for high school
- Natural Resources
Cell Biology Cell biology is the study of cell structure and function, and it revolves around the concept that the cell is the fundamental unit of life. Focusing on the cell permits a detailed understanding of the tissues and organisms that cells compose. Some organisms have only one cell, while others are organized into cooperative groups with huge numbers of cells. On the whole, cell biology focuses on the structure and function of a cell, from the most general properties shared by all cells, to the unique, highly intricate functions particular to specialized cells. The starting point for this discipline might be considered the 1830s. Though scientists had been using microscopes for centuries, they were not always sure what they were looking at. Robert Hooke's initial observation in 1665 of plant-cell walls in slices of cork was followed shortly by Antoine van Leeuwenhoek's first descriptions of live cells with visibly moving parts. In the 1830s two scientists who were colleagues — Schleiden, looking at plant cells, and Schwann, looking first at animal cells — provided the first clearly stated definition of the cell. Their definition stated that that all living creatures, both simple and complex, are made out of one or more cells, and the cell is the structural and functional unit of life — a concept that became known as cell theory. As microscopes and staining techniques improved over the nineteenth and twentieth centuries, scientists were able to see more and more internal detail within cells. The microscopes used by van Leeuwenhoek probably magnified specimens a few hundredfold. Today high-powered electron microscopes can magnify specimens more than a million times and can reveal the shapes of organelles at the scale of a micrometer and below. With confocal microscopy, a series of images can be combined, allowing researchers to
generate detailed three-dimensional representations of cells. These improved imaging techniques have helped us better understand the wonderful complexity of cells and the structures they form. There are several main subfields within cell biology. One is the study of cell 551 energy and the biochemical mechanisms that support cell metabolism. As cells are machines unto themselves, the focus on cell energy overlaps with the pursuit of questions of how energy first arose in original primordial cells, billions of years ago. Another subfield of cell biology concerns the genetics of the cell and its tight interconnection with the proteins controlling the release of genetic information from the nucleus to the cell cytoplasm. Yet another subfield focuses on the structure of cell components, known as subcellular compartments. Cutting across many biological disciplines is the additional subfield of cell biology, concerned with cell communication and signaling, concentrating on the messages that cells give to and receive from other cells and themselves. And finally, there is the subfield primarily concerned with the cell cycle, the rotation of phases beginning and ending with cell division and focused on different periods of growth and DNA replication. Many cell biologists dwell at the intersection of two or more of these subfields as our ability to analyze cells in more complex ways expands. In line with continually increasing interdisciplinary study, the recent emergence of systems biology has affected many biological disciplines; it is a methodology that encourages the analysis of living systems within the context of other systems. In the field of cell biology, systems biology has enabled the asking and answering of more complex questions, such as the interrelationships of gene regulatory networks, evolutionary relationships between genomes, and the interactions between intracellular signaling networks. Ultimately, the broader a lens we take on our discoveries in cell biology, the more likely we can decipher the complexities of all living systems, large and small.
The wide concept of "biotech" or "biotechnology" encompasses a wide range of procedures for modifying living organisms according to human purposes, going back to domestication of animals, cultivation of the plants, and "improvements" to these through breeding programs that employ artificial selection and hybridization. Modern usage also includes genetic engineering as well as cell and tissue culture technologies. The American Chemical Society defines biotechnology as the application of biological organisms, systems, or processes by various industries to learning about the science of life and the improvement of the value of materials and organisms such as pharmaceuticals, crops, and livestock. As per European Federation of Biotechnology, Biotechnology is the integration of natural science and organisms, cells, parts thereof, and molecular analogues for products and services. Biotechnology also writes on the pure biological sciences (animal cell culture, biochemistry, cell biology, embryology, genetics, microbiology, and molecular biology). In many instances, it is also dependent on knowledge and methods from outside the sphere of biology including: bioinformatics, a new brand of computer science bioprocess engineering biorobotics chemical engineering 552 Conversely, modern biological sciences (including even concepts such as molecular ecology) are intimately entwined and heavily dependent on the methods developed through biotechnology and what is commonly thought of as the life sciences industry. Biotechnology is the research and development in the llaboratory using bioinformatics for exploration, extraction, exploitation and production from any living organisms and any source of biomass by means of biochemical engineering where high value-added products could be planned (reproduced by biosynthesis, for example), forecasted, formulated, developed, manufactured and marketed for the purpose of sustainable operations (for the return from bottomless initial investment on R & D) and gaining durable patents rights (for exclusives rights for sales, and prior to this to receive national and international approval from the results on animal experiment and human experiment, especially on the pharmaceutical branch of biotechnology to prevent any undetected side-effects or safety concerns by using the products). By contrast, bioengineering is generally thought of as a related field that more heavily emphasizes higher systems approaches (not necessarily the altering or using of biological materials directly) for interfacing with and utilizing living things. Bioengineering is the application of the principles of engineering and natural sciences to tissues, cells and molecules. This can be considered as the use of knowledge from working with and manipulating biology to achieve a result that can improve functions in plants and animals. [8] Relatedly, biomedical engineering is an overlapping field that often draws upon and applies biotechnology (by various definitions), especially in certain sub-fields of biomedical and/or chemical engineering such as tissue engineering, biopharmaceutical engineering, and genetic engineering.
Biophysics is an interdisciplinary science that applies the approaches and methods of physics to study biological systems. Biophysics covers all scales of biological organization, from molecular to organismic and populations. Biophysical research shares
significant overlap
with biochemistry, nanotechnology, bioengineering, computational and systems biology. Molecular biophysics typically addresses biological questions similar to those in biochemistry and molecular biology, but more quantitatively, seeking to find the physical underpinnings of biomolecular phenomena. Scientists in this field conduct research concerned with understanding the interactions between the various systems of a cell, including the interactions between DNA, RNA and protein biosynthesis, as well as how these interactions are regulated. A great variety of techniques are used to answer these questions. Fluorescent imaging techniques, as well as electron microscopy, x-ray crystallography, NMR spectroscopy, atomic force microscopy (AFM) and small- angle scattering (SAS) both with X-rays and neutrons (SAXS/SANS) are often used to visualize structures of biological significance. Protein dynamics can be observed by neutron spectroscopy. Conformational change in structure can be measured using techniques such as dual polarization interferometry, circular dichroism,SAXS and
553 SANS. Direct manipulation of molecules using optical tweezers or AFM, can also be used to monitor biological events where forces and distances are at the nanoscale. Molecular biophysicists often consider complex biological events as systems of interacting entities which can be understood e.g. through statistical mechanics, thermodynamics and chemical kinetics. By drawing knowledge and experimental techniques from a wide variety of disciplines, biophysicists are often able to directly observe, model or even manipulate the structures and interactions of individual molecules or complexes of molecules. In addition to traditional (i.e. molecular and cellular) biophysical topics like structural biology or enzyme kinetics, modern biophysics encompasses an extraordinarily broad range of research, from bioelectronics to quantum biology involving both experimental and theoretical tools. It is becoming increasingly common for biophysicists to apply the models and experimental techniques derived from physics, as well as mathematics and statistics (see biomathematics), to larger systems such as tissues, organs, populations and ecosystems. Biophysical models are used extensively in the study of electrical conduction in single neurons, as well as neural circuit analysis in both tissue and whole brain.
surroundings Ingestion - take in food Digestion - break down and absorb nutrients from food Egestion - removal of indigestible material Reproduction - the production of new offspring that are similar to the parents Synthesis- a chemical reaction that combine small molecules into larger molecules Transport - the absorption of materials into the organism and distributed throughout the organism (oxygen comes in, carbon dioxide goes out of a cell) Respiration - cellular release of chemical energy from food Aerobic - requires oxygen Anaerobic - doesn't require oxygen Excretion - the removal of waste products from chemical reactions Cells - the basic unit of structure in an organism Unicellular - single celled Multicellular - many cells Growth - the process of becoming larger Development - the process of change during the life span to produce a more complex organism Stimulus - a change in an organisms surroundings that causes a reaction Response - the way an organism reacts to a stimulus Carbohydrates - source of cells energy Proteins and Lipids - building materials Nucleic Acids - generic material/ directs cell activities 554 7. Texts in the natural sciences in english for high school
What Is an Element? An element is a pure substance that cannot be broken down by chemical methods into simpler components. For example, the element gold cannot be broken down into anything other than gold. If you kept hitting gold with a hammer, the pieces would get smaller, but each piece will always be gold. You can think of each kind of element having its own unique fingerprint making it different than other elements. Elements consist of only one type of atom. An atom is the smallest particle of an element that still has the same properties of that element. All atoms of a specific element have exactly the same chemical makeup, size, and mass. There are a total of 118 elements, with the most abundant elements on Earth being helium and hydrogen. Many elements occur naturally on Earth; however, some are created in a laboratory by scientists by nuclear processes. Instead of writing the whole elemental name, elements are often written as a symbol. For example, O is the symbol for oxygen, C is the symbol for carbon, and H is the symbol for hydrogen. Not all elements have just one letter as the symbol, but have two letters - like Al is the symbol for aluminum and Ni is the symbol for nickel. The first letter is always capitalized, but the second letter is not. Symbol names do not always match the letters in the elemental name. For example, Fe is the symbol for iron and Au is the symbol for gold. These symbol names are derived from the Latin names for those elements. Natural resources are available to sustain the very complex interaction between living things and non-living things. Humans also benefit immensely from this interaction. All over the world, people consume resources directly or indirectly. Developed countries consume resources more than under-developed countries. The world economy uses around 60 billion tonnes of resources each year to produce the goods and services which we all consume. On the average, a person in Europe consumes about 36kg of resources per day; a person in North America consumes about 90kg per day, a person in Asia consumes about 14kg and a person in Africa consumes about 10kg of resources per day. In what form do people consume natural resources? The three major forms include Food and drink, Housing and infrastructure, and Mobility. These three make up more than 60% of resource use. International and local trade has its roots in the fact that resources are not evenly distributed on the earth’s surface. Regions with crude oil can drill oil and sell to regions without oil, and also buy resources such as timber and precious metals (gold, diamonds and silver) from other regions that have them in abundance. The uneven distribution is also the root of power and greed in many regions. Some countries use their wealth in resources to control and manipulate regions with fewer resources. Some countries and regions have even gone to war over the management, ownership, allocation, use and protection of natural resources and related ecosystems. 555 Natural Resources A. Overpopulation This is probably the most significant, single threat that natural resources face. The world’s population is increasing at a very fast rate. In the USA, a baby is born every 8 seconds, and a person dies every 13 seconds. The increase in populations mean there will be pressure on almost all natural resources. How? Land Use: With more mouths to feed and people to house, more land will need to be cultivated and developed for housing. More farming chemicals will be applied to increase food production. Many forest or vegetative lands will be converted to settlements for people, roads and farms. These have serious repercussions on natural resources. Forests: Demand for wood (timber), food, roads and forest products will be more. People will therefore use more forest resources than they can naturally recover. Fishing: Fresh water and sea food will face problems too as we will continue to depend heavily on them. Bigger fishing companies are going deeper into sea to catch fish in even larger quantities. Some of the fishing methods they use are not sustainable, thereby destroying much more fish and sea creatures in the process. Need for more: Human's demand for a comfortable life means more items (communication, transport, education, entertainment and recreation) will need to be produced. This means more industrial processes and more need for raw materials and natural resources. B. Climate Change The alteration in climate patterns as a result of excessive anthropogenic is hurting biodiversity and many other a biotic natural resources. Species that have acclimatized to their environments may perish and others will have to move to more favorable conditions to survive. C. Environmental Pollution Land, water and air pollution directly affect the health of the environments in which they occur. Pollution affects the chemical make-up of soils, rocks, lands, ocean water, freshwater and underground water, and other natural phenomena. This often has catastrophic consequences.
In recent years, waste has been viewed as a potential resource and not something that must end up in the landfill. From paper, plastics, wood, metals and even wastewater, experts believe that each component of waste can be tapped and turned into something very useful. Fossil fuel use by the pulp and paper industry in the United States of America declined by more than 50% between 1972 and 2002, largely through energy efficiency measures, power recovery through co-generation and increased use of biomass. Resource recovery is the separation of certain materials from the waste we produce, with the aim of using them again or turning them into new raw materials for
556 use again. It involves composting and recycling of materials that are heading to the landfill. Here is an example: Wet organic waste such as food and agricultural waste is considered waste after food consumption or after an agricultural activity. Traditionally, we collect them and send them to a landfill. In Resource Recovery, we collect and divert to composting or anaerobic digestion to produce biomethane. We can also recover nutrients through regulator-approved use of residuals. Conservation of Natural Resources To have an environmentally sustainable secure future where we can still enjoy natural resources, we urgently need to transform the way we use resources, by completely changing the way we produce and consume goods and services. The case of high resource consumption occurs primarily in the bigger cities of the world. Cities worldwide are responsible for 60-80% of global energy consumption and 75% of carbon emissions, consuming more than 75% of the world’s natural resources. To turn this unfortunate way of life around, we all have to play a role. Education and Public Awareness All stakeholders must aim to provide information and raise public awareness about the wonderful natural resources we have and the need to ensure its health. Even though there is a lot of information in the public domain, campaigners must try to use less scientific terms, and avoid complex terminology to send the message across. Once people understand how useful our natural resources are, they will be better placed to preserve it. Individuals, organizations and nations People and organizations in developed nations with high resource consumption rates must be aware of the issues of natural resources. People should understand that it is OK to enjoy all the items and gadgets at home, but also, give back to the environment by way of reducing waste, recycling waste and becoming a part of the solution. We can achieve this in our homes and workplaces by reducing waste and also by recycling the waste we create. Governments and Policy Governments must enforce policies that protect the environment. They must ensure that businesses and industries play fair and are accountable to all people. Incentives must be given to businesses that use recycled raw materials and hefty fines to those that still tap from raw natural resources. Businesses must return a portion of their profits to activities that aim at restoring what they have taken out of the environment. Natural resource is anything that people can use which comes from nature. People do not make natural resources, but gather them from the earth. Examples of natural resources are air, water, wood, oil, wind energy, iron, and coal. Refined oil and hydro-electric energy are not natural resources because people make them. We often say there are two sorts of natural resources: renewable resources and 557 non-renewable resources. - A renewable resource is one which can be used again and again. For example, soil, sunlight and water are renewable resources. However, in some circumstances, even water is not renewable easily. Wood is a renewable resource, but it takes time to renew and in some places people use the land for something else. Soil, if it blows away, is not easy to renew. - A non-renewable resource is a resource that does not grow and come back, or a resource that would take a very long time to come back. For example, coal is a non- renewable resource. When we use coal, there is less coal afterward. One day, there will be no more of it to make goods. The non-renewable resource can be used directly (for example, burning oil to cook), or we can find a renewable resource to use (for example, using wind energy to make electricity to cook).
Most natural resources are limited. This means they will eventually run out. A perpetual resource has a never-ending supply. Some examples of perpetual resources include solar energy, tidal energy, and wind energy. Some of the things influencing supply of resources include whether it is able to be recycled, and the availability of suitable substitutes for the material. Non- renewable resources cannot be recycled. For example, oil, minerals, and other non- renewable resources cannot be recycled. All places have their own natural resources. When people do not have a certain resource they need, they can either replace it with another resource, or trade with another country to get the resource. People have sometimes fought to have them (for example, spices, water, arable land, gold, or petroleum). When people do not have some natural resources, their quality of life can get lower. So, we need to protect our resources from pollution. For example, when they can not get clean water, people may become ill; if there is not enough wood, trees will be cut and the forest will disappear over time (deforestation); if there are not enough fish in a sea, people can die of starvation. Renewable resources include crops, wind, hydroelectric power, fish, and sunlight. Many people carefully save their natural resources so others can use them in future.
As energy is the main ‘fuel’ for social and economic development, and since energy-related activities have significant environmental impacts, it is important for decision-makers to have access to reliable and accurate data in a user-friendly format. The World Energy Council has for decades been a pioneer in the field of energy resources and every three years publishes its World Energy Resources report (WER), which is released during the World Energy Congress. The energy sector has long lead times and therefore any long-term strategy should be based on sound information and data. Detailed resource data, selected cost data and a technology overview in the main WER report provide an excellent foundation for assessing different energy options based on factual information supplied by the WEC members from all over the world. The work is divided into twelve resource-specific work groups, called Knowledge Networks; complemented by a further three groups investigating the 558 cross-cutting issues of, carbon capture and storage, energy efficiency and energy storage. These Knowledge Networks provide updated data for the website and publications, as well as working on timely deep-dives with a resource focus. An example of a magnetic force is the pull that attracts metals to the magnet. Now, the electrical field induced causes waves, called electromagnetic waves, and they can travel through a vacuum (air), particles or solids. These waves resemble the ripple (mechanical) waves you see when you drop a rock into a swimming pool, but with electromagnetic waves, you do not see them, but you often can see the effect of it. The energy in the electromagnetic waves is what we call radiant energy. There are different kinds of electromagnetic waves and all of them have different wavelengths, properties, frequencies and power, and all interact with matter differently. The entire wave system from the lowest frequency to the highest frequency is known as the electromagnetic spectrum. The shorter the wavelength, the higher its frequency and vice versa. White light, for example, is a form of radiant energy, and its frequency forms a tiny bit of the entire electromagnetic spectrum.
A population comprises all the individuals of a given species in a specific area or region at a certain time. Its significance is more than that of a number of individuals because not all individuals are identical. Populations contain genetic variation within themselves and between other populations. Even fundamental genetic characteristics such as hair color or size may differ slightly from individual to individual. More importantly, not all members of the population are equal in their ability to survive and reproduce. Community refers to all the populations in a specific area or region at a certain time. Its structure involves many types of interactions among species. Some of these involve the acquisition and use of food, space, or other environmental resources. Others involve nutrient cycling through all members of the community and mutual regulation of population sizes. In all of these cases, the structured interactions of populations lead to situations in which individuals are thrown into life or death struggles. In general, ecologists believe that a community that has a high diversity is more complex and stable than a community that has a low diversity. This theory is founded on the observation that the food webs of communities of high diversity are more interconnected. Greater interconnectivity causes these systems to be more
have the option to switch to many other species that occupy a similar role in that ecosystem. In a low diversity ecosystem, possible substitutes for food may be non- existent or limited in abundance. Ecosystems are dynamic entities composed of the biological community and the abiotic environment. An ecosystem's abiotic and biotic composition and structure is determined by the state of a number of interrelated environmental factors. Changes in any of these factors (for example: nutrient availability, temperature, light intensity, grazing intensity, and species population density) will result in dynamic changes to the nature of these systems. For example, a fire in the temperate deciduous forest completely changes the structure of that system. There are no longer any large trees,
559 most of the mosses, herbs, and shrubs that occupy the forest floor are gone, and the nutrients that were stored in the biomass are quickly released into the soil, atmosphere and hydrologic system. After a short time of recovery, the community that was once large mature trees now becomes a community of grasses, herbaceous species, and tree seedlings. An ecosystem includes all of the living things (plants, animals and organisms) in a given area, interacting with each other, and also with their non-living environments (weather, earth, sun, soil, climate, atmosphere). In an ecosystem, each organism has its' own niche or role to play. Consider a small puddle at the back of your home. In it, you may find all sorts of living things, from microorganisms to insects and plants. These may depend on non-living things like water, sunlight, turbulence in the puddle, temperature, atmospheric pressure and even nutrients in the water for life. (Click here to see the five basic needs of living things) This very complex, wonderful interaction of living things and their environment, has been the foundations of energy flow and recycle of carbon and nitrogen. Anytime a ‘stranger’ (living thing(s) or external factor such as rise in temperature) is introduced to an ecosystem, it can be disastrous to that ecosystem. This is because the new organism (or factor) can distort the natural balance of the interaction and potentially harm or destroy the ecosystem. Click to read on ecosystem threats (opens in new page). Usually, biotic members of an ecosystem, together with their abiotic factors depend on each other. This means the absence of one member or one abiotic factor can affect all parties of the ecosystem. Unfortunately, ecosystems have been disrupted, and even destroyed by natural disasters such as fires, floods, storms and volcanic eruptions. Human activities have also contributed to the disturbance of many ecosystems and biomes. Scales of Ecosystems Ecosystems come in indefinite sizes. It can exist in a small area such as underneath a rock, a decaying tree trunk, or a pond in your village, or it can exist in large forms such as an entire rain forest. Technically, the Earth can be called a huge ecosystem.
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