DNA

Deoxyribo nucleic acid or DNA is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms (with the exception of RNA viruses). The main role of DNA molecules is the long-term storage of information. DNA is often compared to a set of blueprints, like a recipe or a code, since it contains the instructions needed to construct other components of cells, such as proteins and RNA molecules. The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in regulating the use of this genetic information. Along with RNA and proteins, DNA is one of the three major macromolecules that are essential for all known forms of life.

DNA consists of two long polymers of simple units called nucleotides, with backbones made of sugars and phosphate groups joined by ester bonds. These two strands run in opposite directions to each other and are therefore anti-parallel. Attached to each sugar is one of four types of molecules called nucleobases (informally, bases). It is the sequence of these four nucleobases along the backbone that encodes information. This information is read using the genetic code, which specifies the sequence of the amino acids within proteins. The code is read by copying stretches of DNA into the related nucleic acid RNA, in a process called transcription.

Within cells, DNA is organized into long structures called chromosomes. These chromosomes are duplicated before cells divide, in a process called DNA replication. Eukaryotic organisms (animals, plants, fungi, and protists) store most of their DNA inside the cell nucleus and some of their DNA in organelles, such as mitochondria or chloroplasts. In contrast, prokaryotes (bacteria and archaea) store their DNA only in the cytoplasm. Within the chromosomes, chromatin proteins such as histones compact and organize DNA. These compact structures guide the interactions between DNA and other proteins, helping control which parts of the DNA are transcribed.

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Carcinoma

A carcinoma is any malignant cancer that arises from epithelial cells. Carcinomas invade surrounding tissues and organs and may metastasize, or spread, to lymph nodes and other sites.

”Carcinoma in situ” (CIS) is a pre-malignant condition, in which some cytological signs of malignancy are present, but there is no histological evidence of invasion through the epithelial basement membrane.

Carcinoma, like all neoplasia, is classified by its histopathological appearance. Adenocarcinoma and squamous cell carcinoma, two common descriptive terms for tumors, reflect the fact that these cells may have glandular or squamous cell appearances respectively. Severely anaplastic tumors might be so undifferentiated that they do not have a distinct histological appearance (undifferentiated carcinoma).

Sometimes a tumor is referred to by the presumptive organ of the primary (eg carcinoma of the prostate) or the putative cell of origin (hepatocellular carcinoma, renal cell carcinoma).

Metastatic carcinoma can be diagnosed through biopsy, including fine-needle aspiration, core biopsy, or subtotal removal of single node.

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Thymine

Thymine is one of the four nucleobases in the nucleic acid of DNA that are represented by the letters G–C–A–T. The others are adenine, guanine, and cytosine. Thymine (T) almost always pairs with adenine, although thymine dimers also occur due to UV light exposure.

This mutation is responsible for melanoma formation. Thymine is also known as 5-methyluracil, a pyrimidine nucleobase. As the name suggests, thymine may be derived by methylation of uracil at the 5th carbon.

In RNA, thymine is replaced with uracil in most cases. In DNA, thymine (T) binds to adenine (A) via two hydrogen bonds to assist in stabilizing the nucleic acid structures.

Thymine combined with deoxyribose creates the nucleoside deoxythymidine, which is synonymous with the term thymidine. Thymidine can be phosphorylated with one, two, or three phosphoric acid groups, creating, respectively, TMP, TDP, or TTP (thymidine mono-, di-, or triphosphate).

One of the common mutations of DNA involves two adjacent thymines or cytosine, which, in presence of ultraviolet light, may form thymine dimers, causing “kinks” in the DNA molecule that inhibit normal function.

Thymine could also be a target for actions of 5-fluorouracil (5-FU) in cancer treatment. 5-FU can be a metabolic analog of thymine (in DNA synthesis) or uracil (in RNA synthesis). Substitution of this analog inhibits DNA synthesis in actively-dividing cells.

Thymine bases are frequently oxidized to hydantoins over time after the death of an organism.

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Worms

Worms are invertebrate species that are not footed. There are worms that live in the land and water while others are parasites that live inside the animal’s body.

There are over 55,000 species of worms. Four main groups are tapeworms, flatworms, gilik worms and roundworms.

Worms are simple structures such as flatworms, microscopic organisms which belong to very small size. However, several parasitic tapeworms that can grow to more than 20 meters. Parasitic worms in the body of animals and plants, some are even inside the human body. Mematoda worm larvae can enter the human kemulut accidentally and penetrated into the lungs. Man will be coughing and swallowing the larvae, so that the larvae enter the stomach. In the stomach they eat foods that are eaten by humans. Adult worms lay eggs and the eggs can be discarded with the feces. The eggs of this parasite can infect other people.

WORMS LAND

Earthworms belong roundworms or annelids. Soil earthworms swallow and digest the plant material contained therein. Earthworm body consists of a row of rings. The body is covered with fine hairs that serve to help move the body. Including animal hermaphrodite earthworms.

SEA WORMS

The structure of marine worms or Polychaeta Annelid not much different, except for fine hairs on the surface of its body is longer. Marine worms eat the plants but also many who hunt marine worms poked by long vessels (proboscis) to catch prey.

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Gene Therapy

Gene therapy is a technique that introduces an altered gene into a person’s body to carry out the work of a mulfunctioning gene. The procedure aims to treat or cure diseases that have been caused by faulty genes.

There are more than 4000 genetic disorders, and that number is likely to increase as we discover more about our DNA. Many of these diseases are incurable.

Gene therapy is attempts to cure genetic disorders by replacing a defective gene in the human body with a properly functioning gene.

The first FDA-approved gene therapy procedure was performed by Dr. French Anderson in September 1994, on a child born with a rare genetic disorder, known as severe combined immunodeficiency. This caused her to have no effective immune system, resulting in frequent infections, and a poor quality of life.

The procedure consisted of removing the child’s white blood cells, inserting the good functional copies of the desired gene into some of the cells, and then putting them back into her body. The procedure is not a permanent fix, and needs to be performed every few months. But she’s alive and well and has a strengthened immune system.

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Lymph System

Lymph system is a system of transport lymph fluid from tissues into the blood. The system also contains cells that make the body able to ward off disease.

When blood flow throughout the circulatory system, a liquid substance called lymph seeps through capillary walls. This liquid deliver oxygen and nutrients essential to the tissue cells. Lymph fluid dispose of substances and return the rest seeps into the bloodstream through capillary walls.

Every day about 24 liters of lymph fluid seeps through capillary walls into the tissue. Most of the back behind kealiran seeping blood. However, approximately 4liter of them still remained in the network. Lymphatic system transports waste materials are called nodes and build it through the blood vessels of the chest.

Nodes form a clear liquid that carries dissolved substances, cellular debris, and pathogens such as bacteria and viruses. Lymph flow only toward unity is out of the network. Unlike blood, pumped by the heart, lymph through the lymph system with the help of muscle-skeletal muscles, which pushes the fluid when they contract. Valves in lymph vessels to prevent fluid to flow backwards.

As lymph fluid flows through lymph vessels, he crossed the lymph node. This is where white blood cells called macrophages and swallowing cum cellular debris and pathogens. Other white blood cells called lymphocytes produce antibodies, ie chemicals that target the pathogens for destruction. Organs of the other nodes have the same role. Lymphocytes and macrophages work together to form the immune system, the body’s most powerful defenses to ward off disease.

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Chromatin

Chromatin is that portion of the cell nucleus which contains all of the DNA of the nucleus in animal or plant cells. (A small amount of special DNA is also found in the mitochondria of the cell cytoplasm outside of the cell nucleus.)

DNA is never found as a naked molecule in animal or plant cell nuclei. DNA is always found in association with histone proteins (soluble in acid solutions), HMG proteins (soluble in neutral saline), residual proteins (soluble in concentrated urea solutions), phosphoproteins (soluble in basic solutions), RNA species (soluble in aqueous phenol solutions), and lipid species (soluble in chloroform-methanol solutions). By choosing the appropriate solution, it is possible to extract each of these classes of macromolecules away from the DNA and away from the other chromatin constituents.
Smaller molecules such as steroid and thyroid hormones and vitamins A and D are also found within the cell nucleus bound to DNA or to one of the other chromatin macromolecules. These small molecules are transported to the nucleus, where they play stimulatory roles for RNA and DNA synthesis on chromatin. Viral RNA species and DNA species can also play stimulatory roles on chromatin. Some RNA species are confined to the cell nucleus, where they are synthesized on chromatin and feed back on other segments of chromatin to influence RNA or DNA synthesis.

Foreign substances such as antibiotics (actinomycin D), dyes (acridine orange), enzymes (DNase I), and complex carbohydrates (phytohemagglutinin) also penetrate the cell nucleus to the chromatin, where they also may have stimulatory or inhibitory effects on RNA or DNA synthesis.

When cells divide, the chromatin is seen as distinct chromosomes, duplicating, with an equal partition of each set of chromosomes then traveling to each of the new daughter cells. When the new chromosomes reach the new cells, they begin to un-ravel into long thin extended 10 nm. (100 A.) microfibrils called euchromatin or condensed coiled masses called heterochromatin. The study of euchromatin and heterochromatin while within intact non-dividing cells, or after isolation from such cells, has revealed that RNA synthesis occurs only in euchromatin, and not in heterochromatin. Similarly, DNA synthesis is early in euchromatin and late in heterochromatin. Mechanisms for controlling RNA or DNA synthesis in chromatin can be studied by additions or deletions of macromolecules from either isolated euchromatin or isolated heterochromatin. Such studies reveal that histone proteins are largely inhibitory, while RNA and other proteins are largely stimulatory for RNA and DNA synthesis.

The Chromatin Network is dedicated to researchers and all others interested in the study of animal and plant chromatin as found in the cell nucleus. It is evident that by such study of chromatin, we will gain a deeper understanding of gene action and gene regulation, of hormone and vitamin action and regulation, of viral action and viral regulation, and of the general physiologic processes of embryogenesis, organ regeneration, the neoplastic process, and the immune process.

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Flowering Plant

Flowering plant or Angiospermae is most successful plant. Angiospermae reproduce by seed that grows inside the flower ovary. Angiospermae derived from the Greek word which means seed enclosed.

Growth angiospermae embryo enclosed in a special structure called a seed inside the flower. After the fertilization process, seeds are protected by the fruit flesh. Thus, flowering plants have a greater chance to survive and produce offspring.

Flowering plants are believed to have evolved from ancient conifers (now extinct) who lived about 250juta years ago, namely the Permian period. And in its development, flowering plants affect other living organisms.

There are two groups of flowering plants. Each is distinguished by way of the formation of leaf buds from the seeds of growth. The first group is a monocot, is a single seeds. And the group keua is dicotyledonous, ie plants that have two seed pieces.

Interest contents

In general, flower consists of four organs: the head (leaf sheath), petala (corolla), stamen or stamens (the anthers and stem juice), and pistils (the stigma, pistil stalk, and ovaries).

In the middle there are flower stamen and pistil. Stamens on the inside leaf crown. Each stamen consists of anthers that produce male sex cells called pollen, and pollen stalk that attaches anthers to the stigma.

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Bacteria

Bacteria are single-celled microorganisms which their structure is simpler than the cells making up the bodies of animals and plants. Bacteria can be found in every place. The bacteria breed in soil, air, even in our digestive system.

Most of the types of bacteria that are not classified as dangerous organisms. However, some species belonging to pathogenic bacteria can cause disease. According to its shape, pathogenic bacteria are divided into three groups. Coccus-shaped bacteria and can cause a hoarse throat, ulcers, and pneumonia. Elongated rod-shaped bacteria hasilus that can cause typhoid and salmonella. Spirokaeta spiral-shaped bacteria and can cause Lyme disease and syphilis.

Bacteria infiltrate into the body through various ways, namely through the sprinkling of water is inhaled from the air, the skin wound, water or food that is swallowed, and reproductive systems. When bacteria enter the body successfully, the bacteria eat, splitting, and release toxic substances that can harm human cells. Usually the immune system can recognize bacteria and destroy it immediately. Infection also can be treated with antibiotics. Bacterial infections can be prevented by immunization, personal hygiene, including clean drinking water, and clean the wound with antiseptic.

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