Tissue and Organ Formation

The tissues just described form organs and organ systems that are much the same in all vertebrates. To get a general sense of how this happens, start with a sperm and egg. Recall that these develop from germ cells, which are immature reproductive cells. (All other cells in the body are “somatic”, after the Greek word for body.) After a zygote forms at fertilization, mitotic cell divisions produce an early animal embryo. In vertebrates, the cells soon become arranged as three primary tissues-ectoderm, mesoderm, and endoderm. These are embryonic forerunners of all tissues in the adult. Ectoderm gives rise to the skin’s outer layer and to tissues of the nervous system. Mesoderm gives rise to the tissues of muscle, bone, and most of the circulatory, reproductive, and urinary systems. Endoderm gives rise to the gut’s lining and organs derived from it.

You might think we are stretching things a bit when we say that each one of those systems contributes to the survival of all living cells in the body. After all, what could the body’s bones and muscles have to do with the life of a tiny cell? Yet interactions between the skeletal and muscular systems allow us to move about toward sources of nutrients and water, for example. Parts of those systems assist blood circulation, as when contractions of leg muscles help move blood in veins back to the heart. The bloodstream transports nutrients and other substances to individual cells, and transports secreted products and wastes away from them.

MUSCULAR SYSTEM
Movement of internal body parts movement of whole body maintenance of posture heat production.

INTEGUMENTARY SYSTEM
Protection from injury, dehydration, and some microorganisms; control of body temperature; excretion of some wastes; reception of external stimuli.

NERVOUS SYSTEM
Detention of external and internal stimuli control and coordination of responses to stimuli integration of activities of all organ systems.

URINARY SYSTEM
Maintenance of the volume and composition of extracellular fluid. Excretion of blood-borne wastes.

SKELETAL SYSTEM
Support, protection of body parts sites for muscle attachment, body cell production, and calcium and phosphate storage.

CIRCULATORY SYSTEM
Rapid internal transport of many materials to and from cells helps stabilize internal temperature and pH.

REPRODUCTIVE SYSTEM
Male: Production and transfer of sperm to the female. Female: Production of eggs provision of a protected, nutritive environment for developing embryo and fetus. Both systems have hormonal influences on other organ systems.

RESPIRATORY SYSTEM
Delivery of oxygen to cells removal of carbon dioxide wastes produced by cells pH regulation.

DIGESTIVE SYSTEM
Ingestion of food, water preparation of food molecules for absorption elimination of food residues from the body.

LYMPHATIC SYSTEM
Return of some tissue fluid to blood roles in immunity (defense against specific invaders of the body).

ENDOCRINE SYSTEMHormonal control of body functioning works with nervous system in integrative tasks.

Bacteria And Viruses

The unseen multitudes

Did a friend even mention that you are nearly 1/1000 of mile tall? Probably not. What would be the point of measuring people in units as big as miles? Yet we think this way, in reverse, when we measure microorganisms. These are mostly single-celled organisms too small to be seen without a microscope.

Of all organisms, bacteria generally are the smallest. To be sure, viruses are smaller. We measure them in nanometers (billionths of a meter). But viruses are not living things. We consider them here because they infect just about every kind of organism in the great spectrum of life.
1. Bacteria are microscopically small, single-celled prokaryotic organisms. They do not have a profusion of internal, membrane-bound organelles in the cytoplasm, as eukaryotic cells do. Yet bacteria show great metabolic diversity, and many make complex behavioral responses to the environment.
2. Today there are two great bacterial lineages, the archaebacteria and dubacteria. Archaebacteria live in such inhospitable, anaerobic habitats that they may resemble the first living cells on earth. Most bacterial species are eubacteria, which inhabit nearly all existing environments.

3. Bacteria reproduce by binary fission, a cell division mechanism that immediately follows DBA replication and that divides the parent cell into two genetically equivalent daughter cells.
4. Nearly all viral multiplication cycles include five steps: attachment to a suitable host cell, penetration, viral DNA or RNA replication and protein synthesis, assembly of new viral particles, and release from the infected cell.

Do you know about thyroid functioning and parathyroid functioning

Thyroid functioning

The human thyroid gland is at the base of the neck in front of the trachea, or windpipe. It is main hormones, thyroxine and triiodothyronine, have widespread effects on most cells. They are critical for normal development of many tissues, and they control overall metabolic rates in humans and other warm-blooded animals. Their importance is brought into sharp focus by cases of abnormal thyroid secretion.

The synthesis of thyroid hormones requires iodine, which is obtained from the diet. In the absence of iodine, blood levels of these hormones decrease. The anterior pituitary responds to this by secreting a thyroid stimulating hormone (TSH). Because the thyroid hormones cannot be synthesized, the feedback signal continues and so does TSH secretion. Excess TSH overstimulates the thyroid gland and causes it to enlarge. The enlargement is a form of goiter. Goiter caused by iodine deficiency is no longer common in countries where people use iodized salt.

Hypothyroidism results from insufficient concentrations of thyroid hormones. Hypothyroid adults often are overweight, sluggish, dry-skinned, intolerant of cold, and sometimes confused and depressed. Affected women often have menstrual disturbances. Hyperthyroidism results from excess concentrations of thyroid hormones. Hyperthyroid adults show an increased heart, rate, elevated blood pressure, weight loss despite normal caloric intake, intolerance of heat, and profuse sweating. Typically they are nervous, agitated, and have trouble sleeping.

Parathyroid functioning

Some endocrine glands do not respond directly to other hormones or nerves. They respond homeostatically to chemical change in the immediate surroundings. The parathyroid glands are like this. Four such glands are positioned next to the back of the human thyroid. They secrete parathyroid hormone (PTH) when the concentration of calcium ions in their surroundings decreases. Their action affects how much calcium is available for enzyme activation, muscle contraction, blood clotting, and many other tasks.

PTH stimulates bone cells to release calcium and phosphate ions, and stimulates the kidneys to conserve them. PTH also helps activate vitamin D. The activated form, a hormone, enhances calcium absorption from ingested food. In vitamin D deficiency, too little calcium and phosphorus is absorbed, so bones develop improperly. This ailment is called rickets.

Hormonal responses to the external environment influence growth, development, and reproduction in predictable ways. The pineal gland, a photosensitive organ in the brain, provides a good example of this. In the absence of light, the pineal gland secretes the hormone melatonin. Thus bood levels of melatonin vary from day to night, and they vary with the changing seasons. The variations influence the development of primary reproductive cycles and reproductive behavior in a variety of species.

Consider the hamster. In winter, when nights are longest, melatonin levels are high and sexual activity is suppressed. In summer, when days are longer, melatonin levels are low-and hamster sex peaks. Or consider a male white-throated sparrow. Melatonin suppresses growth of the bird’s gonads until spring, when days start to lengthen. Then, stepped-up gonadal activity leads to the production of hormones that influence singing behavior. With his distinctive song, the sparrow defines his territory and may hold the interest of a mate.
Does melatonin also influence human behavior? Perhaps, it seems possible that decreased melatonin secretion triggers puberty, the age at which human reproductive organs and structures start to mature. In cases where disease has destroyed the pineal gland, puberty begins prematurely, the focus essay mentions some other interesting possibilities.

Do You need Alcohol?

You can make alcohol from almost anything edible. Through a process called fermentation, sugars are converted into ethanol alcohol. This chemical is readily absorbed into the bloodstream and has a powerful effect on the body and mind. Stronger alcohol, called sprits, and often called hard liquor, are made through distillation in which alcohol is heated to concentrate the ethanol. Eifferent societies use different ingredients and processes to make alcohol. In southern Europe, grapes are traditinally fermented to make wine-a process first introduced by the Romans.

Nothern European countries are famous for their beers brewed from grain and hops. Grapes are also the main ingredient of another famous French spirit called brandy. Other spirits include gin, vodka, and whisky.

How to affect the body?

Although it comes in different forms and strengths, alcohol has basically the same effects when you drink it. At first these may be pleasant. You may feel rather warm, light-headed, and relaxed.

However, the more you drink, the worse you will feel. As more alcohol enters your bloodstream, you will find it increasingly difficult to perform physical tasks. You will lose your coordination and sense of balance, knocking things over and feeling unsteady on your feet. Your speech will become slurred and difficult for other people to understand.

If you drink a lot very quickly, alcohol can kill. It can affect the brain so badly that the heart or breathing stops. Drinking too much can make people feel very sick the next day, and it can take days for their bodies to recover.

Liver?

The liver is the organ in your body that breaks down and eliminates poisons like alcohol. It has been likened to a car with one gear that just goes at one speed-the liver can burn up only one unit of alcohol an hour. Liver cells that have too much alcohol to process die and are replaced by fatty tissue.

Drinkig heavily over a number of years puts great strain on the liver, which can become so scarred that it no longer works properly. This is known as cirrhosis. Heavy drinking also contributes to other conditions like heart disease, hepatitis, and stomach problems such as bleeding and ulcers. It can cause men to become sexualy impotent and by interfering with th ebalance of hormones in the body alcohol increases the risk of breast cancer in women. Mothers who drink heavily when pregnant can severely damage their unborn children.

People who drink heavily for a long time can become addicted to alcohol. those who develop an emotional or physical dependency on drink are known as alcoholics. Alcoholism usually takes years to develop. Early signs include constantly needing to have liquor available and being unusually resistant to its effects. In the later stages, however, people gradually lost control over their drinking. Alcoholics often suffer from unpleasant conditins like shaking, various body pains, and redness in the face. They can experience severe withdrawal effects if they suddenly stop. Unlike coming off other drugs, sudden alcohol withdrawal can actually kill.

Treatment programs for alcohol addiction can be very effective. Some people go to drying out clinics for help, others join groups like Alcoholics Anonymous for support in giving up alcohol. Alcoholics Anonymous has over two million members throughout the world.

Wine cooler - This is fruity drink with alcohol added (alcohol content is 4%-8% only)

Beer - This is Fermented mixture of grains and water (alcohol 3%-10% only)

Wine - This is Fermented grape juice (alcohol content 8%-14% only)

Liqueurs - This is sweetened and flavored spirits (alcohol content 20%-40%)

Spirits _ This is alcoholic drink concentrated by distillation (alcohol 38%-45%)

Is Smoking must for your life?

Cigarette?

Cigarettes are made mainly from tobacco, the dried leaf of the plant Nicotiana tabacum. The main components of cigarettes include nicotine, a powerful drug that quickly leads to addiction. Carbon monoxide, the same gas that comes out of car exhausts, is the principal gas in cigarette smoke. Other chemicals include many that have links with cancer in humans, such as arsenic, benzene, cadmium, and formaldehyde.

What happens when you smoke?

When you take a puff on a cigarette, many things happen. in just a few seconds, nicotine is delivered to the brain. This stimulates the body's central nervous system, increasing the heart rate and blood pressure.

What happens Pregnant Woman smoking?

Pregnant women who smoke are putting the baby's health at serious risk. The baby is m oe likely to be born prematurely, or to die in the uterus (womb) or shortly after birth. Babies born to smokers are often smaller. They get less oxygen in the womb, which makes their hearts beat faster and slows their growth.

Bad Symptoms when you smoking?

Lung cancer

Emphysema (An often fatal lung disease, which destroys the walls of the air sacs).

Stroke (Blood loss to the brain. Often fatal or severely disabling).
Lowered fertility
Heart Attack
Tobacco amblyopia
Cancer of the cervix (in women)
Peripheral vascular disease (disease of the arteries in the leg)
Gangrene (Death and decay of part of the body due to loss of blood supply when fatty deposits, caused by smoking, clog up the arteries.
Chronic bronchitis (Inflammation of the bronchial tubes leading into the lungs,resulting in coughing, wheezing, and fever.
Mouth and throat cancer
Aortic aneurysm (A swelling of the main artery in the body, with the risk of rupture and fatal blood loss).
Peptic ulcers (Raw and painful areas in the intestines.

Free of cost smoking! (passive smoking)

For most people, breathing in other people's cigarette smoke causes minor symptoms like watering eyes, itching nose and throat, and dizziness. But for some the effects are more serious. Babies and young children may suffer from more infections and serious chest conditions like bronchitis and pneumonia. People exposed to passive smoking over long periods are also at a 10 to 30 percent increased risk of death from lung cancer.

People may choose to smoke because they believe it makes them look grown-up or sophisticated. Very often these people become addicted to tobacco and then are unable to quit smoking when they want to.

All smokers know they would be better off if they gave up. Unfortunately, kicking the habit is not easy. Nicotine is as addictive as heroin, and psychological cravings.

Most find that the first few days are the hardest, since nicotine withdrawal causes unpleasant symptoms such as lack of concentration, lightheadedness, anxiety, coughing, hunger, and strong cravings. These usually pass within a week or so.

What happens after last puff

20 mins later : Blood pressure and pulse return to normal.
one day later : Lungs start to clear out mucus and other deposits
Two days later : Body is clear of nicotine
Three days later : Breathing becomes easier
2 to 12 weeks later : Circulation improves
3 to 9 months later : Lungs become more efficient
1 year later : Excess risk of heart disease is halved
10 years later : Risk of lung cancer reduced by half
15 years later : Risk of death from lung cancer, heart disease and stroke return to non-smoking levels.

Do you know Drugs?

A drug is a substance or chemical that affects the way your body or your mind works. Some drugs are artificially made. Others come from plants, minerals, and even animals.

When someone mentions drugs, we often think of illegal substances like heroin, cocaine, or cannabis, but there are many other kinds of drugs. medicines are often made up from chemicals in a laboratory.

You can take drugs in various ways. When you drink or swallow them, they enter the bloodstream via the stomach. Some are smoked or inhaled via the lungs. Others are administered by injection. With patches, suppositories, or creams, the active ingredients are absorbed through the skin.

Drugs are strongs substances. They can have powerful effects on our bodies and our minds. Alcohol and cigarettes are widely regarded as "social" drugs meaning that groups of people can enjoy them together. People who become dependent on alcohol or cigarettes often find it hard to socialize without a drink or cigarette.

How to control of Drugs?

Medicinal drugs are controlled in different ways. some, like many painkillers, can be bought freely in drugstores and supermarkets. Most however, are available only by prescription from a doctor.

Many people drink alcohol because they like the taste, but most people take illegal drugs to make them feel different. However, most illegal drugs can make you feel very bad indeed. You never know how you will react to an illegal or abused substance.

A lot of depends on the mood you are in when you take a drug. As with alcohol, drugs also affect your reactions . You will find it more difficult to control how you feel and what you do if something happens to you.

Do you know drug varieties? their bad feelings?

Amphetamines - Anxiety, panic

Cannabis - Paranoia, panic

Ecstasy - Nausea, fatigue and depression after use.

Solvents - Hangovers, drowsiness

Heroin - Nausea, vomiting

Cocaine and

and crack cocaine - Insomnea, bad mood.

LSC/Muschrooms - Walking nightmares, paranoia

Sedatives - Nausea, vomiting.

How quickly you become addicted depends on how much and how oftern you take the drugs, as well as on your personality and circumstances. Even if most drugs don't lead to addiction, they can be habit forming. The temptation is to take them more and more frequently. Once addicted to a drug, people will do anything to get their next fix even break the law.

People used to think that all drugs were extremely dangerous and takign them inevitably led to addiction and death. Although this put a lot of people off drugs, many others discovered that this simply was not true.

Root Canal Treatment

Root canal treatment, commonly called us RCT. why we are calling it as Root canal treatment is because the tooth has two parts. the outer part or upper part that which we can see in a mouth of a individual is called as crown.

This inner part or lower part of a tooth which we cannot see is called as Root. it is inside out bone, tissues are lovering this part.

Inside this root part we are having the blood supply and nerve for the tooth. This part is called as root canal. It also extends to the crown part as palp chamber and pulp worms. The hole tissue part is called as dental palp.

In a caris affected tooth when the bacteria enters pulp tissue, it will cause periupical inflammation and it will leads to severe pain. In this cases we are doing root canal treatment.

In a root canal treatment first thing what we are doing is, we will get a food access through the crown to remove the pulp in the root canals for this we will remove some part of tooth material in specified manner using a instrument.

After that we will remove the pulp tissue by using special instruments called as broaches. Next to this we will enlarge this size of the canals with the help of specific instruments like treatment and filer with copious irrigation we are obtian the specific size.

After this procedure we will fill the root canals with a insert material called as Gutta percha and we will seal the apical part of root thus we are preventing the infections. After this procudures we can fill the tooth with permanent filling in a permanent crown.

Root canal treatment can be done is a single sitting procedure or a multi sitting procedure. This will take two or three sittings.