Selasa, 19 Januari 2010

what is biology?

Chapter I

Most of the important questions of today can be considered from philosophical, social, and scientific standpoints. None of these approaches individually presents a solution to most problems. For example, it is a fact that the human population of the world is growing very rapidly. Philosophically, we may all agree that the rate of population growth should be slowed. Science can provide information about why populations grow and which actions will be the most effective in slowing population growth. Science can also develop methods of conception control that would limit a person’s ability to reproduce. Killing infants and forced sterilization are both methods that have been tried in some parts of the world within the past century. However, most would contend that these “solutions” are philosophically or socially unacceptable. Science can provide information about the reproductive process and how it can be controlled, but society must answer the more fundamental social and philosophical questions about reproductive rights and the morality of controls. It is important to recognize that science has a role to play but that it does not have the answers to all our problems. However, it will be able to help humans to solve most of their problem if they try to develop their knowledge about science. One of the basic science which is able to give some helps to solve human problem is biology. How can biology give some help to solve human’s problem? Of course it because biology is the science of living things. When human understand about the important of biology, they will be able to understand about the importance of life. Automatically, they will be easier to face some problem of life. Further more, as the students of Biology Department, it will be more important for us to learn and to built our understanding about Biology. We should be able to answer the question “What is Biology?” because it is a basic for us to develop our knowledge about biology.

B.Problem Formulation
1.What is the importance of biology?
2.What is life?
3.What is the future direction of biology?

This letter is written based on the following purposes:
1.To built an understanding about the importance of biology in human’s life.
2.To make clear about the definition of life
3.To understand the future direction of biology

The benefits which are able to be found from this handing out are as follows:
1.We will be able to be sure that biology is extremely important in our life.
2.We will be able to understand the definition of life exactly
3.We will be able to realize the future direction of biology


A.Biology as a science
Science begins with curiosity about the world and a desire to understand it. Science involves testing ideas about how thins work and how they are made, thereby modifying ideas and developing knowledge. Through the process of questioning and observation of ourselves and the things about us, similarities, differences and patterns are perceived, investigated, measured and classified. In Europe, since the fifteenth century, science has been on advance. Developments had been based on accurate observations, carefully devised experiments and the collection of numerical data that is then handled mathematically. The word “science” itself a relatively recent one, originating in the nineteenth century. However, the concept of science is exactly much older than that.
Do you know when did science start? The beginning of science may date back to the earliest human life. Our earliest ancestors survived at the expense of the wild plants and animals around them. From the outset, the quality of human observations played a key part in survival.

The position of Biology is as the science. The word science is a noun derived from a Latin term (scientia) meaning knowledge or knowing. In its more restricted contemporary sense, science is a system of acquiring knowledge based on scientific method, and to the organized body of knowledge gained through such research. Humans have accumulated a vast amount of “knowledge” using a variety of methods, some by scientific methods and some by other methods. Science is distinguished from other fields of study by how knowledge is acquired, rather than by the act of accumulating facts. Science is actually a process used to solve problems or develop an understanding of natural events that involves testing possible answers. The process has become known as the scientific method. The scientific method is a way of gaining information (facts) about the world by forming possible solutions to questions followed by rigorous testing to determine if the proposed solutions are valid (valid = meaningful, convincing, sound, satisfactory, confirmed by others). A scientific method seeks to explain the events of nature in a reproducible way, and to use these reproductions to make useful predictions. It is done through observation of natural phenomena, and/or through experimentation that tries to simulate natural events under controlled conditions. It provides an objective process to find solutions to problems in a number of scientific and technological fields.
When using the scientific method, scientists make several fundamental assumptions. There is a presumption that:
1. There are specific causes for events observed in thenatural world,
2. That the causes can be identified,
3. That there are general rules or patterns that can beused to describe what happens in nature,
4. That an event that occurs repeatedly probably has thesame cause,
5. That what one person perceives can be perceived by others, and
6. That the same fundamental rules of nature apply regardless of where and when they occur.

This approach can be used by scientists to solve particular practical problems, such as how to improve milk production in cows or to advance understanding of important concepts such as evolution that may have little immediate practical value. Yet an understanding of the process of evolution is important in understanding genetic engineering, the causes of extinction, or human physiology—all of which have practical applications. The scientific method requires a
systematic search for information and a continual checking and rechecking to see if previous ideas are still supported by new information. If the new evidence is not supportive, scientists
discard or change their original ideas. Scientific ideas undergo constant reevaluation, criticism, and modification. The scientific method involves several important identifiable components, including careful observation, the construction and testing of hypotheses, an openness to new
information and ideas, and a willingness to submit one’s ideas to the scrutiny of others. However, it is not an inflexible series of steps that must be followed in a specific order. This scientific method involves making hypotheses about observations and testing the validity of the hypotheses. When hypotheses are disproved, they can be revised and tested in their new form. Throughout the scientific process, people communicate about their ideas. Theories and laws develop as a result of people recognizing broad areas of agreement about how the world works. Current laws and theories help people formulate their approaches to scientific questions. To make it clear, we are able to see the scientific method in its sequence below:
Observation is the process by which perceptions of objects or events are selected, interpreted and their significance judged. Scientific inquiry often begins with an observation that an event has occurred repeatedly. An observation occurs when we use our senses (smell, sight, hearing, taste, touch) or an extension of our senses (microscope, tape recorder, X-ray machine, thermometer) to record an event. Observation is more than a casual awareness. The information gained by direct observation of the event is called empirical evidence (empiric = based on experience; from the Greek empirikos = experience). Empirical evidence is capable of being verified or disproved by further observation.
b.Questioning and exploration
The formation of the questions is not as simple as it might seem because the way
the questions are asked will determine how you go about answering them. A question that is too broad or too complex may be impossible to answer; therefore a great deal of effort is put into asking the question in the right way. In some situations, this can be the most time-consuming part of the scientific method; asking the right question is critical to how you look for answers. Once a decision has been made about what question to ask, scientists explore other sources of knowledge to gain more information. After exploring the appropriate literature, a decision is made about whether to continue to explore the question. If the scientist is still intrigued by the
question, a formal hypothesis is constructed and the process of inquiry continues at a different level.
c.Constructing Hypotheses
Hypothesis is a statement that provides a possible answer to a question or an explanation for an observation that can be tested. Hypothesis ca also be defined as a tentative explanation for an observed event. To be a scientific, a hypothesis must be testable by means of predictions and investigations. A good hypothesis must be logical, account for all the relevant information currently available, allow one to predict future events relating to the question being asked, and be testable. Furthermore, if one has the choice of several competing hypotheses one should use the simplest hypothesis with the fewest assumptions.
d.Testing Hypotheses
Set up an experiment that will allow you to test your hypothesis using a control group and an experimental group. Control groups are the variables which must be controlled in the investigation and not allowed to vary at all. Meanwhile, the experimental group consists of the dependent variable and the independent variable. Independent variable is the condition that is changed systematically in an experiment, for instance, in an experiment in which seedings are grown in the different temperatures, so temperature will be used as the independent variable. Whereas the dependent variable is the effect or the out come from the alteration of independent variable. A common method for testing a hypothesis involves devising an experiment. An experiment is a recreation of an event or occurrence in a way that enables a scientist to support or disprove a hypothesis. If the processes of questioning and experimentation
continue, and evidence continually and consistently supports the original hypothesis and other closely related hypotheses, the scientific community will begin to see how these hypotheses and facts fit together into a broad pattern. When this happens, a theory has come into existence.
e.The development of theories and laws.
A theory is a widely accepted, plausible generalization about fundamental concepts in science that explain why things happen. It can be widely accepted because it had been done by sing the sequence of scientific method, hence it can be received by society. Whereas, a scientific law is a uniform or constant fact of nature that describes what happens in nature. An example of a biological law is the biogenetic law, which states that all living things come from preexisting living things. While laws describe what happens and theories describe why things happen, in one way laws and theories are similar. They have both been examined repeatedly and are regarded as excellent predictors of how nature behaves. In the process of sorting out the way the world works, scientists use generalizations to help them organize information. However, the generalizations must be backed up with facts. The relationship between facts and generalizations is a two-way street. Often as observations are made and hypotheses are tested, a pattern emerges which leads to a general conclusion, principle, or theory. This process of developing general principles from the examination of many sets of specific facts is called induction or inductive reasoning. Meanwhile, when general principles are used to predict the specific facts of a
situation, the process is called deduction or deductive reasoning. In the process of science,
both induction and deduction are important thinking processes used to increase our nderstanding of the nature of our world. Noteworthy, the most important thing to develop the thory and law of science is the existence of communication. For the most part science is conducted out in the open under the critical eyes of others who are interested in the same kinds of questions. An important
part of the communication process involves the publication of articles in scientific journals about one’s research, thoughts, and opinions. The communication can occur at any point during the process of scientific discovery. And finally, people can share and support one another to develop the theory and law of science.
Now, we are able to understand that a science should be got by using the scientific method in its sequence. Accordingly, we can understand that biology is also a science, because we need to do a series of scientific method if we want to find a fact of biology.

B.Science and nonscience
We have realized that biology is a science. But, can we differ science from nonscience? As we know that both scientists and nonscientists seek to gain information and improve understanding of their fields of study. But, the differences between science and nonscience are based on the assumptions and methods used to gather and organize information and, most important, the way the assumptions are tested. The difference between a scientist and a nonscientist is that a scientist continually challenges and tests principles and assumptions to determine a cause-and-effect relationship, whereas a nonscientist may not be able to do so or may not believe that this is important. For example, a historian may have the opinion that if President Lincoln had not appointed Ulysses S. Grant to be a General in the Union Army, the Confederate States of America would have won the Civil War. Although there can be considerable argument about the topic, there is no way that it can be tested. Therefore, it is not scientific. This does not mean that history is not a respectable field of study. It is just not science.
Unscience known as pseudoscience (pseudo = false). It is not science but uses the appearance or language of science to convince, confuse, or mislead people into thinking that something has scientific validity. When pseudoscientific claims are closely examined, it is found that they are not supportable as valid or reliable. The area of nutrition is a respectable scientific field, however, there are many individuals and organizations that make unfounded claims about their products and diets. We all know that we must obtain certain nutrients like amino acids, vitamins, and minerals from the food we eat or we may become ill. Many scientific experiments have been performed that reliably demonstrate the validity of this information. However, in most cases, it has not been demonstrated that the nutritional supplements so vigorously advertised
are as useful or desirable as advertised. Rather, selected bits of scientific information (amino acids, vitamins, and minerals are essential to good health) have been used to create
the feeling that additional amounts of these nutritional supplements are necessary or that they can improve your health. In reality, the average person eating a varied diet will obtain all of these nutrients in adequate amounts and nutritional supplements are not required. In addition, many of these products are labeled as organic or natural, with the implication that they have greater nutritive value because they are organically grown (grown without pesticides or synthetic fertilizers) or because they come from nature. The poisons curare, strychnine, and nicotine are all organic molecules that are produced in nature by plants that can be grown organically, but we wouldn’t want to include them in our diet.
However, many fields of study have both scientific and nonscientific aspects. The style of clothing worn is often shaped by the artistic creativity of designers and shrewd marketing by retailers. Originally, animal hides, wool, cotton, and flax were the only materials available and the choice of color was limited to the natural color of the material or dyes extracted from nature. The development of synthetic fabrics and dyes, machines to construct clothing, and new kinds of fasteners allowed for new styles and colors. Similarly, economists use mathematical models and established economic laws to make predictions about future economic conditions. However, the reliability of predictions is a central criterion of science, so the regular occurrence of unpredicted economic changes indicates that economics is far from scientific. Many aspects of anthropology and sociology are scientific in nature but they cannot be considered true sciences because many of the generalizations in these fields cannot be tested by repeated experimentation. They also do not show a significantly high degree of cause and effect, or they have poor predictive value.

C.Biology as the Science of Life
We have known Biology is a science. But, for more complete understanding, we should realize that biology is the science of life. The word biology simply means the study of life. Biology is concerned with the study of all living things, from bacteria to higher plants and mammals. Biology is also a modern science, although it has ancient origins. Biology aims to provide understanding of the structure and function of organisms and how they interact with one another.
We know that biology is the science of life. However, the word “Life” and “Science” are words that we use frequently, and without apparent difficulty. But, it is surprisingly hard to say what we mean by life and by science. What do we mean? Let’s start with life because the position of biology as a science have been explain above.
All activities of living things make up “life” as biologist understand the word. It is not a fully satisfactory definition to say that life is what living thins do. Living things are known as organisms. When organisms are studied in biology in any details, it usually turns out that the underliying process within one type of organism are very similar to those occurring within organisms of other types. All organism have a great deal in common, even though they may look and behave very differently. Consequenlty, for biologists, “LIFE” is identified as a combination of characteristics common to all living organisms and absent from non-living things. The site of life is the cell, the functioning unit structure of which living thing are made.

D.The characteristic of Life
Living things have special abilities and structures not typically found in things that were never living. The ability to manipulate energy and matter is unique to living things. Energy is the ability to do work or cause things to move. Matter is anything that has mass and takes up space. Developing an understanding of how living things modify matter and use energy will help you appreciate how living things differ from nonliving objects. Living things show five characteristics that the nonliving do not display. There are eight characteristics activities common to all organisms. They are respiration, nutrition, metabolism, excretion, sensitivity, locomotion, reproduction, and growth. The possession and practice of these characteristic activities of organism is the way for biologist to identify and define life.
Respiration is the process by which sugars such as glucose and certain other substance are broken down to release chemical energy for other life process such us protein synthesis and growth. Respiration occurs in living cell, and take place in very many steps. Each step involves enzymes and at several of stages energy is released. Some of this energy is transferred to other molecules and is available to be used in other reactions. The reactions of respiration inside cells are known as tissue respiration and they are dependent upon haseous exchange between the organism and the environment. Most respiration requires oxygen, and is known as aerobic respiration. The final breakdown product from aerobic respiration are carbondioxide and water. Meanwhile, respiration in the absence of air is known as anaerobic respiration. It may take place in cells that have been deprived of air.
Nutrition is the process by which the organism obtains the energy to maintain the function of life, and matter to create and maintain their structure. Energy and matter are obtained from nutrients. There are a few different methods of nutrition which is done by the organisms. Most plants are autotrophs, it means that they make their own organis nutrients (food) from an external supply of relative simple raw materials (inorganic nutrients), using energyfrom sunlight in photosynthesis. Alternatively, and much more rarely, the energy source is a specific chemical reaction which is known as chemosynthesis. Autothrops go on to make all their other requirements from the products of photosynthesis (or chemosynthesis) by combining them with each other and with additional inorganic nutrients. Animals are heterotrophs. This means that they depend upon existing foods (organic nutrients) which have to be broken down before they can be used. Humans and animals also known as holozoic organism which take food into the body, digest it, and finally absorbed the soluble product of digestion to fulfill their requirement of energy. A few animals (such as plasmodium) also known as parasitic organism which live on or inside the host organism and feed on the living host.
The metabolism of organism is the total of the chemical process of life that take place within it. Living things has an ability to make chemical substance , including many different types of molecule and some very large molecules. Living things also break down substance. So we can divided that metabolism into process that involve building-up molecules, known us anabolism, and those that involve breaking molecules, known as catabolism. In anabolism simple chemicals are combined to make complex molecules. Some of which are stored as energy sources for later use. Examples of anabolism include starch synthesis from glucose, and protein synthesis from amino acids. In catabolism complex compounds are broken down with release of energy. Respiration, I which glucose is broken down and energy is released, is an example of catabolism. The reactions of metabolism is not haphazard or accidental, but are controlled by the organism. For example, each step is catalyzed by a different enzyme. The cell nucleus controls which enzymes are present in a cell. Consequently the cell nucleus indirectly controls metabolism. Metabolism also results in the productions of substances of no furtger use to the organism. Some of them even harmful and are excreted.
Metabolic processes involve the total of all chemical reactions and associated energy changes that take place within an organism. This set of reactions is often simply referred to as metabolism (metabolism = Greek metaballein, to turn about, change, alter). Energy is necessary for movement, growth, and many other activities. The energy that organisms use is stored in the chemical bonds of complex
molecules. The chemical reactions used to provide energy and raw materials to organisms are controlled and sequenced. There are three essential aspects of metabolism: (1) nutrient
uptake, (2) nutrient processing, and (3) waste elimination. All living things expend energy to take in nutrients (raw materials) from their environment. Many animals take in these materials by eating or swallowing other organisms. Microorganisms and plants absorb raw materials into their
cells to maintain their lives. Once inside, nutrients enter a network of chemical reactions. These reactions manipulate nutrients in order to manufacture new parts, make repairs, reproduce, and provide energy for essential activities. However, not all materials entering a living thing are valuable to it. There may be portions of nutrients that are useless or even harmful. Organisms eliminate these portions as waste. These metabolic processes also produce unusable heat energy, which may be considered a waste product.
Excretion is the elimination of the unwanted products of metabolism and of substances present in excess within the organism. For example, respiration produces excretory product in every living cell. Aerobic respiration produces carbon dioxide and water. Green plants produce oxygen in the light as an excretory product of photosynthesis. Animal excrete nitrogenous waste product such as ammonia, urea, or uric acid. Excretion also involves eliminating any axcess or toxic substance taken in with the diet, including water and salt.
Responsive or sensitivity is the ability of an organism to respond to a stimulus . a stimulus might be an external event such as change in light intensity, or it might be an internal like the arrival of food in the stomach. In animals a stimulus is detected by its sensory organs, such as its eyes. In plants there are no obvious sensory organs but certai cells are able to detect specific stimuli such as gravity and light. The response to a stimuli might be the movement of the whole animal, perhaps in pursuit or away from danger, or of part of the animal, such as a hand jerking away from a hot object. In plants, the response is always made by an organ such as leaf stalk, stem or tendril. A response to an internal stimulus might be the secretion of enzymes in response to food, or the production of antibodies in response to an invading microbe. In general the responses of organisms are adaptive, in that an organism alters its environment by moving from a less favourable to a more favourable position. Alternatively, the organism may make modifications to the way it works to the way it behaves or to its sturectures, and as a result be better suited to the environment. Some organisms can tolerate adverse conditions or adapt themselves better that others. In most animals there is a system of receptors or sense organs that detect changes, together with nerves that carry electrical impulses to organs which make a response. Responses are bought about by effector organs such as muscles or glands. Plants lack such a sophisticated sensory and nervous system, yet their sensitivity is well developed. Plant responses tend to be comparatively slow growth responses, brought about by growth substances or hormones. Plants are extremely sensitive to changes in the environment, however, even though they lacj the complez sense organs of some animals. In fact almost all organisms, including some single cell organisms of quite simple structure, are highly sensitive.
Organisms also respond to changes within their bodies and in their surroundings in a meaningful way. These responsive processes have been organized into three categories:
irritability, individual adaptation, and adaptation of populations, which is also known as evolution. Irritability is an individual’s ability to recognize a stimulus and rapidly respond to it, such as your response to a loud noise, beautiful sunset, or noxious odor. The response
occurs only in the individual receiving the stimulus.

Movement and Locomotion is one of the most obvious characteristics of living things. The movement of many animals are speedy and efficient, but most plants and some animals lead a generally stationary life. Animal movements are usually associated with obtaining food, finding mates or escaping from predators. In contrast, most plant movements are relatively slow growth movements, involving only part of the organism. They occur in response to an environmental stimulus.
Reproduction is the ability of organisms to produce their individuals of the same species. Reproduction may involve a sexual process, or it may be a sexual. In sexual reproduction, special sex cells or gametes are formed. Two gametes fuse in a process known as a fertilization to form form a new cell called a zygote. The zygote grows into a new individual. Some organisms have elaborated mechanisms of parental care of the developing offspring or progeny. In sexual reproduction the progeny are very similar to their parents, but not identical to them. Sexual reproduction is the name for reproduction that does not involve a sexual process. In some organisms asexual reproduction is achieved by a simple division (fission) of a parent cell or body into two or more offspring, or fragmentation of the parent body to yield parts that are capable of developing into new individuals. Other organisms produce special spores. In yet others, individuals bud off from the parent organisms. These indviduals are genetically identical to each other and to their parent.
Since all organisms eventually die, life would cease to exist without reproduction. There are a number of different ways that various kinds of organisms reproduce and guarantee their continued existence. Some kinds of living things reproduce by sexual reproduction in which two
individuals contribute to the creation of a unique, new organism. Asexual reproduction occurs when an individual organism makes identical copies of itself.
Growth and Development which also the characteristic of living thing should be defined separately. Growth is defined as an irreversible increase insize of the organism and is usually accompanied by an increase in solid materials and the amount of cell materials. Development involves the change in shape and form of an organism as it matures. Most animals have a limited period of growth and development which results in an adult of characteristic size and form. Most plants and a few animals grow throughout their entire life, at least during particular season of the year. All organisms are constantly breaking down and rebuilding their structures, but the components can vary over the life of the organism.

E.Why should we study biology?
Biology is important for us to be learnt. Biology plays such a valuable part in general education that there is hardly any need to justify its study further. Issues that are biologically based crop up in everyday experiences. for example: When we know why we should have thanked a green plant today! As we seek to understand the behavior of our pets, and our fellow human beings; When we read that a toddler has mum’s eyes, dad’s ears and the milk man’s teeth; As we relax in a nature reserve, work in the garden or walk in the park; When we choose food and drink from the supermarket and collet a prescription from the chemist; When we support a greenpeace campaign, or argue about defence and nuclear weapons; When we read about develoments in biotechnologies new and old; When we discuss the ethies of transplant surgery or embryo experimentation; And when we communicate concern about increasing atmospheric levels of carbon dioxide, about the destruction of the ozone layer, and the issues of word hunger and human lifestyles,east and west, north and south.
Moreover, what study in an Advanced level course may be relevant to us whatever our ultimate employment. Some people with hingher qualifications in biology move into work that does not use their subject directly. But such people hardly ever regard their study of biology as wasted. Biology may in fact be directly useful to you in finding employment. Biologist are employed in laboratory work, in industry, fieldwork, agriculture, horticulture forestry, health care, work with animals, marine and freshwater biology, information science and in teaching or lecturing. All these opportunities arise through some from of further or higher education, following your Advanced or BTech level course.

F.Future Directions in Biology
Where do we go from here? Although the science of biology has made major advances, many problems remain to besolved. For example, scientists are seeking major advances in the control of the human population and there is a continued interest in the development of more efficient methods of producing food. One area that will receive much attention in the next few years is the relationship between genetic information and such diseases as Alzheimer’s disease, stroke, arthritis, and cancer. These and many other diseases are caused by abnormal body chemistry, which is the result of hereditary characteristics. Curing certain hereditary diseases is a big job. It requires a thorough understanding of genetics and hemanipulation of hereditary information in all of the trillions of cells of the organism.
Another area that will receive much attention in the next few years is ecology. Climate change, destruction of natural ecosystems to feed a rapidly increasing human population, and pollution are all still severe problems. Most people need to learn that some environmental changes may be acceptable and that other changes will ultimately lead to our destruction. We have two tasks. The first is to improve technology and increase our understanding about how things work in our biological world. The second, and probably the moredifficult, is to educate, pressure, and remind people that their actions determine the kind of world in which the next generation will live.
It is the intent of science to learn what is going on in these situations by gathering the facts in an objective manner. It is also the role of science to identify cause-and-effect relationships and note their predictive value in ways that will improve the environment for all forms of life. Scientists
should also make suggestions to politicians and other policymakers about which courses of action are the most logical from a scientific point of view. SUMMARY

The conclusions of this topic are as follows:
1.Biology is important to be learnt because it is the study of life.
2.Life is identified as the combination of characteristics common to all living thngs and absent from non-living things.
3.There are two basic future direction of biology, they are as follows:
a.To improve technology and increase the understanding of human about how things work in our biological word.
b.To educate, pressure, and remind people that their actions will determine the kind of world in the next generation.

1.The readers should learn more and understand more about the importance of biology.
2.It will be better for the readers to compare literatures one another to get the best understanding.

Anonima. 2009. “Science.”
Anonimb. 2009. “Characteristics Of Living Things.”
Karmana, Oman. 2007. “Biologi.” Bandung: Grafindo Utama.
Ross, enger. 2002. “Concepts In Biology Tenth Edition”. USA: The McGraw-Hill

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