Rabu, 18 November 2015

Scientific report contains the formulation of problems and hypothesis, goal, method, result, discussion, and conclusion

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The results of science experiment need to the recorded in the form of a science report. It contains a description of experiment written in concise form. The description should be clear and systematic, outlining the following points; the formulation of problem and hypothesis, goal, method, result, discussion, and conclusion.

The Formula of problem and Hypothesis
The experiment is started with a question  (or question), then followed by hypothesis formulation. For example, the question is why does plant A grow better in open spaces than plant B does in shaded in shaded places? The hypothesis is that sunshine affects the rate of growth of plant A

To understand the aim of an experiment, one can answer these question
1.       Why does the experiment need to be performed?
2.       What problem will be solved?
3.       What hypothesis will be tested?

For example, the aim of the sample experiment to is to know the effect of light towards the growth of plant A.

Method is a description of the steps we are going to take and how to pursue them. Besides, we also need to record species used in the experiment, tools and chemicals, and controls to be set. In the sample, we need a flux meter to measure light intensity and ruler or vernier calipers to measure plant height and diameter, in order to determine the growth.

See picture

The results of experiments are the data collected. During research, data can be obtained or read as results. For instance, the sample will yield data on the height of plants on varying light intensity including the control. Also, limited qualitative data can be obtained such as the characteristics of the leaves, stem, and root. All data should be recorded well.

Data need to be presented concisely and systematically. It will help other to understand the result of the experiment. To choose the best form of presentation of data, one need to know the data type. If the data quantitave. It can be presented in the form of schemes or a detailed description. For example, the characteristic of an organism can be presented by describing morphology (shape, size, and color) or the developmental process of an organism such as the stages of butterfly metamorphosis. If the data is quantitave. Such as number, presentation can be in the form of tables, diagram, and graph.

The discussion of the result should be whether they support or do not support the hypothesis. Reliability and validity of the results should be considered, whether there are any errors in the results and what the magnitude of these errors would be. Additional relevant information can be collected from scientific books and articles. They act as additional support or comparison toward the results.
A scientific article is a published version of experimental results. Scientific article can be found in scientific journals or periodicals. Generally, the structure of a scientific article are introduction, content, and conclusion.


The conclusion is the summary of the results and discussion of the experiment. It is made by answering the initial aim. Again, the result may or may not support the hypothesis.

Selasa, 17 November 2015

Several Steps In a Scientific, Formulating problems, Proposing Hypotesis, Drawing Conclusion

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A person who studies biology is called a biologist. Biologists learn about nature not only from reading but also from investigating organism and the phenomena of life directly. The investigation and study are done systematically; a process called a scientist method.

Scientist Method
Scientist work scientifically by a scientific method. It is away or series of steps of action that are followed by scientists in doing scientific investigation or research. It can be formulated in several steps.

Formulating a Problem
Scientific investigation is started when a question arises in regard to the natural world For example, we see two plants growing in two different places, one is in open-lighted space (plant A) and the other is in shaded space (plant B). we may ask then why the growth of plant A is better than plant B

See Formulating Problem and question

Proposing a Hypothesis
Problem which are formulated in the form of question will raise proposed responses. These responses are temporary answers or hypothesis toward the formulated problem.

A hypothesis is often based on previous knowledge and scientific research. They can be obtained from books, journal articles, newspaper, internet or quotations.

In the case, the hypothesis will be plant A grows better in open space than plant B in shaded place because sunshine affects the rate of growth of plant A.

Performing an Experiment
Hypothesis need to be tested or proven by performing an experiment. Before the actual experiment, measures on the kinds of materials and tools to used and affecting variables have to be determined

Determined Tools and Material
Before conducting an experiment, the tools and material have to be determined. Besides, the limitations of resources, including the available funds, have to be taken in to account.

The limitations of resources will greatly affect the proposed experiment. As an example, to know whether temperature plays a role in plant growth, there has to be a thermometer available. If it is not, the temperature cannot be measured accurately and its effects to plant growth will still be In question.

Determining Variables
The next step is determining the variables of the experiment. Variables are the characteristics of the objects which can be measured quantitatively and may have changing values. For example, the growth of the plant has height as its variable.

There are two kinds of variables in an experiment, independent and depend.

Independent variable is the variable that is changed or manipulated by the subject of experiment, while the dependent variable is the variable that changes due to the experiment.

In many biological experiment, there are usually two groups of treatment: a treatment group which receives treatment and a control group (i.e a group not receiving treatment). The treatment that are given to the group are based on the availability of tool, materials, and funds.

As an example, an experiment is done with the title, “ The Effect of Light Intesity towards Plant Grow”. The treated groups in this experiment receive a varying light intensity, while the control group is kept out in the open space. In this case, light intensity is the independent variable and plant growth is the dependent one. Meanwhile, all other variables that are not under investigation such as temperature and water are kept equal for both in threat and control groups. In order to ensure a fair test.

After tools, material, and variables are determined, the experiment, “The Effect of Light Intensity towards Plants Growth”, is started by placing plant A in spaces where light intensity varies. If it does not grow well where the light intensity is low, then we know that light is needed for growth. However, we still have to perform a controlled group by planting in a region with constant light intensity. This particular plant is the control or standard plant.

All the plants in the experiment should receive equal treatment for all other variables. Those are the kinds of the plant, the size of the port, the type of the soil, and the amount of water. It is very important that experiment is done in batches or repetition to ensure valid and reliable results.

Drawing Conclusions
After an experiment is done, conclusions can be drawn. A conclusion contains the results of the experiment. It may or may not support the formulated hypothesis.

Scientific Attitude
In researching an organism or phenomenon, biologists should be have scientifically. Scientific thinking and attitude will be useful in solving daily problem or phenomenon. They are explained below

1. Able to differentiate between facts and opinions

2. Honest and truth towards facts.

3. Courage based on hospitality in raising question and argumentation.

4. Exploring curiosity

5. Concern towards the environment.

6. Starting opinion or arguments scientifically and critically.

7. Dare to suggest improvement and be willing to be responsible for it

8. Cooperative

9. Discipline and perseperance

Senin, 16 November 2015


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The role of biology in the field of medicine is especially aimed at the prevention, diagnosis, and treatment of disease and disorder. Here are some example of the use of biology in medicine.

  1. Organ transplant has given solution to those having medical problems because of organ defects.
  2. Virology has contributed to the medical wold by providing a framework to develop vaccines.
  3. Creating babies by in vitro fertilization has given option for couple unable to have babies by conventional means.
  4. Medical microbiology has succeded indetifying many human pathogenic bacteria so that countering antibiotic can be produced 

Animal Farming

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Biology Plays a major part in the development of production of farm animals. Here are some example of the use of biology in animal farming.

  1. Artificial insemination is developed by the advancement of animal anatomy, physiology, genetics, and embryology. This technique aims for obtaining carttle with high quality and increased production.
  2. Development of in vitro fertilization; in this technique, embryo is produced ex-uterus (outside the womb) of the female parent. Before embryos are implanted (attached to the uterus inner wall of the female cattle), they can be stored for a period of time liquid nitrogen of-196-C. Cattle can than be selected based on the best embryos, rather than replying on random mating to occur. In this way only the best cattle are selected to breed each time, thereby improving the overall quality of the herd. 

Rabu, 11 November 2015

Importance Biology Agriculture

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The increase in human population carries with it the need for for increased and more efficient food production. Biology has played a significant role on the improvement of food production in agriculture. Some of the example are:
  1. Farmers used to plant crops traditionally using conventional tools. With the advancement of biology and technology, they now can plant crops in many different cultivation ground along with more efficient cultivation methods
  2. Through the development of biotechnology and molecular biology, plant have been genetically engineered to produce their own pesticide. So they no longer need to be spayed manually. Among those plants are apples, pear, cabbage, broccoli, and potatoes.
  3. Plants can be propagated quickly and in large quantity by tissue culture technique. The example are palm trees, orchids, bananas, and carrots
  4. Genetic Engineering has produced seedless fruits such as watermelon, papaya, orange and grape.

Importance Of Biology Agriculture, Animal Farming, Medicine And Industri

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Along with the development of technology, biology plays an important role in life. Biology is beneficial in the field of agricultural, animal farming, medicine, and industry.

  1. Agriculture
  2. Animal Farming
  3. Medicine
  4. Industri

Jumat, 06 November 2015

How To develop The Use Of Microorganisms

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Have you ever wondered why pimples or acnes appear when you start puberty? Or have you ever thought of what happen to your heart during exercise? What about where honey come from? What makes mangoes smell different to durian? Biology can answer those sort of questions

Biology is the study of life the term comes from greek words bios that means life and that logos that means study or knowledge why do we need to study about life?

Biology affects our daily lives, environment, the food we consume, and the disease that attact us. Understanding biology can help us to.

  1. Understand ourselves and the life around us.
  2. Improve our life quality, in using natural resources for our daily needs, preventing disease, and developing new ways of using other organisms;
  3. Giving positive effects to the environment such as conserving natural habitat, preserving endangered species, and reducing the effects pollution.
Biology can help us to develop the use of microorganism

Selasa, 20 Oktober 2015

Rhizopus on Bread and Rhizopus Structure

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Have you ever observed moldy bread? The mold on the bread is a type of fungi from the group of Zygomycota.

The body of Zygomycota is composed of hyphae that lack septum. Some part of hyphae differentiate into sporangium that is supported by the sporagiophore (figure). Sporangium spore. Sexual reproduction produces vegetative walled and black zygosporangium (plural: zygosporangia). Zygomycota refer to the fungal sexual reproduction system. They do not have fruiting bodies

Habitat Zygomycota

Zygomycota mostly lives as saprophytes on terrestrial region, food, or the remains of living organism. Some are also found living as parasites that cause disease in humans and plants. Other live in a mutualistic symbiosis as lichens or mycorrhiza.

Kamis, 30 Juli 2015

Composed of Nucleic Acid and Protein Envelope Virus

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A Virus is not a cell (acellular). A virus contains a particle called virion, which can be crystallized and shows a mineral characteristics rather than life. For that matter, some scientists consider viruses as non-living. Still, other think the opposite because viruses can reproduce which is a characteristic of life. Nevertheless, viral reproduction can only be done inside a living cell. The cell in which the virus resides is called the host cell.

Because a virus is not a cell, it does not have cellular component such as the cell membrane, cytoplasm, and nucleus. A virus is composed of a nucleic acid and protein coat called a capsid.

Nucleic Acid

Nucleic Acid Are the molecules that carry the genetic information. A virus has only one type of the nucleic acids, i.e. DNA or RNA

The genetic material may be in the shape of single of double stranded chain, circular, or linier.

Protein Envelope (capsid)

The protein coat covering the genetic material is called the capsid

Composed of a large number protein subunits called capsomers. The capsid giving the virus its shape. It can be a helical structure of capsomeres, giving the virus its rod shape, or polyhedral, or a more complex shape

The T shape virus has a head and tail part and the head is usually polyhedral and the tail is composed of three structures called sheath, base plate, and tail fibers. The base plate and tail fiber are used to attach and infect cell. An example of one of these complex viruses is the T shape bacteriophage.

Body and structure of a virus. Virus is composed of nucleid acid and capsid

a. helical such as tobacco mossaic virus
b. polyhedral such as adenovirus
c.complex such as Bacteriophage
d.virus with envelope in influenza

Nucleic acid and capsid from a structure called nucleocapsid. In some viruses, the nucleocapsid. In some viruses, the nucleocapsid has a membrane called envelope. it is composed of lipids and protein and helps the virus to infect cells. An example of a virus with an envelope is the Influenzavirus. Viruses without an envelope are called naked virusses

Minggu, 26 Juli 2015

Virus Structure

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All viruses contain the following two components: 1) a nucleic acid genome and 2) a protein capsid that covers the genome. Together this is called the nucleocapsid. In addition, many animal viruses contain a 3) lipid envelope. The entire intact virus is called the virion. The structure and composition of these components can vary widely. 

A: Viral Genomes: While the genomes of all known cells are comprised of double stranded DNA, the genomes of viruses can be comprised of single or double stranded DNA or RNA. They can vary greatly in size, from approximately 5-10 kb (Papovaviridae, Parvoviridae, etc.) to greater than 100-200 kb (Herpesviridae, Poxviridae). The known structures of viral genomes are summarized below. 

All viruses contain the following two components: 1) a nucleic acid genome and 2) a protein capsid that covers the genome. Together this is called the nucleocapsid. In addition, many animal viruses contain a 3) lipid envelope. The entire intact virus is called the virion. The structure and composition of these components can vary widely. 

A: Viral Genomes: While the genomes of all known cells are comprised of double stranded DNA, the genomes of viruses can be comprised of single or double stranded DNA or RNA. They can vary greatly in size, from approximately 5-10 kb (Papovaviridae, Parvoviridae, etc.) to greater than 100-200 kb (Herpesviridae, Poxviridae). The known structures of viral genomes are summarized below. 

DNA: Double Stranded - linear or circular
          Single Stranded - linear or circular
          Other Structures - gapped circles
RNA: Double Stranded - linear
          Single Stranded - linear : These single stranded genomes can be either + sense, - sense, or ambisense The sense         strand is the one that can serve directly as mRNA and code for protein, so for these viruses, the viral RNA is infectious. The viral mRNA from - strand viruses is not infectious, since it needs to be copied into the + strand before it can be translated. In an ambisense virus, part of the genome is the sense strand, and part is the antisense.
The genome of some RNA viruses is segmented, meaning that a virus particle contains several different molecules of RNA, like different chromosomes.

B: Protein Capsid
 Viral genomes are surrounded by protein shells known as capsids. One interesting question is how capsid proteins recognize viral, but not cellular RNA or DNA. The answer is that there is often some type of "packaging" signal (sequence) on the viral genome that is recognized by the capsid proteins. A capsid is almost always made up of repeating structural subunits that are arranged in one of two symmetrical structures, a helix or an icosahedron. In the simplest case, these "subunits" consist of a single polypeptide. In many cases, however, these structural subunits (also called protomers) are made up of several polypeptides. Both helical and icosahedral structures are described in more detail below. 

1) Helical Capsids: The first and best studied example is the plant tobacco mosaic virus (TMV), which contains a SS RNA genome and a protein coat made up of a single, 17.5 kd protein. This protein is arranged in a helix around the viral RNA, with 3 nt of RNA fitting into a groove in each subunit. Helical capsids can also be more complex, and involve more than one protein subunit.
A helix can be defined by two parameters, its amplitude (diameter) and pitch, where pitch is defined as the distance covered by each turn of the helix. P = m x p, where m is the number of subunits per turn and p is the axial rise per subunit. For TMV, m = 16.3 and p= 0.14 nm, so P=2.28 nm. This structure is very stable, and can be dissociated and re-associated readily by changing ionic strength, pH, temperature, etc. The interactions that hold these molecules together are non-covalent, and involve H-bonds, salt bridges, hydrophobic interactions, and vander Waals forces.

Several families of animal virus contain helical nucleocapsids, including the Orthomyxoviridae (influenza), the Paramyxoviridae (bovine respiratory syncytial virus), and the Rhabdoviridae (rabies). All of these are enveloped viruses (see below). 

2) Icosahedral Capsids: In these structures, the subunits are arranged in the form of a hollow, quasi spherical structure, with the genome within. An icosahedron is defined as being made up of 20 equilateral triangular faces arranged around the surface of a sphere. They display 2-3-5 fold symmetry as follows:
- an axis of 2 fold rotational symmetry through the center of each edge.
- an axis of 3 fold rotational symmetry through the center of each face.
- an axis of 5 fold rotational symmetry through the center of each corner.
These corners are also called Vertices, and each icosahedron has 12.
Since proteins are not equilateral triangles, each face of an icosahedron contains more than one protein subunit. The simplest icosahedron is made by using 3 identical subunits to form each face, so the minimum # of subunits is 60 (20 x 3). Remember, that each of these subunits could be a single protein or, more likely, a complex of several polypeptides.
Many viruses have too large a genome to be packaged inside an icosahedron made up of only 60 polypeptides (or even 60 subunits), so many are more complicated. In these cases, each of the 20 triangular faces is divided into smaller triangles; and each of these smaller triangles is defined by 3 subunits. However, the total number of subunits is always a multiple of 60. The total number of subunits can be defined as 60 X N, where N is sometimes called the Triangulation Number, or T. Values for T of 1,3,4,7,9, 12 and more are permitted.

When virus nucleocapsids are observed in the electron microscope, one often sees apparent "lumps" or clusters on the surface of the particle. These are usually protein subunits clustered around an axis of symmetry, and have been called "morphological units" or capsomers

C: Viral Envelope
In some animal viruses, the nucleocapsid is surrounded by a membrane, also called an envelope. This envelope is made up of a lipid bilayer, and is comprised of host-cell lipids. It also contains virally encoded proteins, often glycoproteins which are trans-membrane proteins. These viral proteins serve many purposes, such as binding to receptors on the host cell, playing a role in membrane fusion and cell entry, etc. They can also form channels in the viral membrane.
Many enveloped viruses also contain matrix proteins, which are internal proteins that link the nucleocapsid to the envelope. They are very abundant (ie, many copies per virion), and are usually not glycosylated. Some virions also contain other, non-structural proteins that are used in the viral life cycle. Examples of this are replicases, transcription factors, etc. These non-structural proteins are present in low amounts in the virion.
Enveloped viruses are formed by budding through cellular membranes, usually the plasma membrane but sometimes an internal membrane such as the ER, golgi, or nucleus. In these cases, the assembly of viral components (genome, capsid, matrix) occurs on the inside face of the membrane, the envelope glycoproteins cluster in that region of the membrane, and the virus buds out. This ability to bud allows the virus to exit the host cell without lysing, or killing the host. In contrast, non-enveloped viruses, and some enveloped viruses, kill the host cell in order to escape.

D: Virus Classification/Nomenclature
Viruses are classified using a combination of characteristics, including the following
1) Morphology: size, shape, presence of envelope, etc.
2) Physicochemical properties: thermal stability, detergent stability, molecular mass, etc.
3) Genome: size, type of nucleic acid, strandedness, etc.
4) Proteins: number, size, sequence, etc.
5) Lipids: content, character, etc.
6) Carbohydrates: content, character, etc.
7) Genome organization and replication: strategy of replication, number and position of open reading frames, transcriptional and translational strategies, site of virion assembly and release.
8) Antigenic properties: serological relationships.
9) Biological properties: Host range, mode of transmission, pathogenicity, tissue tropisms, geographic distribution, etc.

Using these and other criteria, the International Committee on Nomenclature of Viruses (ICTV) produced the following the hierarchical system for viral classification.
1) Orders (virales): Groupings of families of viruses that share common characteristics and are distinct from other orders and families.
2) Families (-viridae): Groupings of genera of viruses that share common characteristics and are distinct from the member viruses of other families.
3) Subfamilies (-virinae): Not used in all families, but allows for more complex hierarchy of taxa.
4) Genera (-virus): Groupings of species of viruses that share common characteristics and are distinct from the member viruses of other species.
5) Species (virus); The definition accepted by ICTV is "a virus species is defined as a polythetic class of viruses that constitutes a replicating lineage and occupies a particular ecological niche". A species can be further broken down into strains, variants, etc.

In addition to this formal taxonomy, David Baltimore proposed that viruses be classified according to the nature of their genome and the relationship between the genome and the viral mRNA. The classes that he proposed are the following:
Class I: Double Stranded DNA Genomes
Class II: Single Stranded DNA Genomes
Class III: Double Stranded RNA Genomes
Class IV: Positive Strand RNA Genomes
Class V: Negative Strand RNA Genomes
Class VI: Retroviruses

So, the classification of viruses is quite complex, and to some extent is constantly evolving.