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# internal and external parts of human body

From Wikipedia

Normal human body temperature

Normal human body temperature, also known as normothermia or euthermia, is a concept that depends upon the place in the body at which the measurement is made, and the time of day and level of activity of the person. There is no single number that represents a normal or healthy temperature for all people under all circumstances using any place of measurement.

Different parts of the body have different temperatures. Rectal and vaginal measurements, or measurements taken directly inside the body cavity, are typically slightly higher than oral measurements, and oral measurements are somewhat higher than skin temperature. The commonly accepted average core body temperature (taken internally) is (). The typical oral (under the tongue) measurement is , or . In Russia and former Soviet countries, the commonly quoted value is 36.6|Â°C|Â°F, based on an armpit (axillary) reading. Although some people think of these numbers as representing the normal temperature, a wide range of normal temperatures has been found. In adult men and women the normal range for oral temperature is 33.2|â€“|38.2|C|F, for rectal it is 34.4|â€“|37.8|C|F, for the Tympanic cavity it is 35.4|â€“|37.8|C|F and for axillary it is 35.5|â€“|37.0|C|F.

The time of day and other circumstances also affects the body's temperature. The core body temperature of an individual tends to have the lowest value in the second half of the sleep cycle; the lowest point, called the nadir, is one of the primary markers for circadian rhythms. The body temperature also changes when a person is hungry, sleepy, or cold.

## History

In the early 18th century, Gabriel Fahrenheit originally used human body temperature as a reference point for his temperature scale, defining it to be 100Â°F. Later redefinition of his scale to use the boiling point of water as a reference point caused the numerical value for normal body temperature to drift.

In 1861, Carl Reinhold August Wunderlich released his summary of the armpit, or axillary, temperatures of twenty five thousand people, and reported the mean to be 37.0|Â°C|Â°F, with a range of 36.25|Â°C|Â°F to 37.5|Â°C|Â°F. He also identified the natural variations in temperature throughout the day and the variations between individuals, as well as differences based on sex and age, which were largely ignored in favor of an oversimplified single number. Wunderlich's thermometers were not calibrated to a standard settingâ€”in 1861, no standard had been agreed uponâ€”and he never explained his methods for compiling and describing the data he had collected, which would have been a monumental task before the availability of basic calculating machines. The one surviving, hand-made thermometer reads significantly higher than modern thermometers.

## Variations

Temperature control (thermoregulation) is part of a homeostatic mechanism that keeps the organism at optimum operating temperature, as it affects the rate of chemical reactions. In humans the average oral temperature is 36.8|C, though it varies among individuals. However, no person always has exactly the same temperature at every moment of the day. Temperatures cycle regularly up and down through the day, as controlled by the person's circadian rhythm. The lowest temperature occurs about two hours before the person normally wakes up. Additionally, temperatures change according to activities and external factors.

Normal body temperature may differ as much as () between individuals or from day to day.

### Natural rhythms

Body temperature normally fluctuates over the day, with the lowest levels around 4 a.m. and the highest in the late afternoon, between 4:00 and 6:00 p.m. (assuming the person sleeps at night and stays awake during the day). Therefore, an oral temperature of () would, strictly speaking, be normal in the afternoon but not in the morning. An individual's body temperature typically changes by about () between its highest and lowest points each day.

Body temperature is sensitive to many hormones, so women have a temperature rhythm that varies with the menstrual cycle, called a circamensal rhythm. A woman's basal body temperature rises sharply after ovulation, as estrogen production decreases and progesterone increases. Fertility awareness programs use this predictable change to identify when a woman is able to become pregnant. During the luteal phase of the menstrual cycle, both the lowest and the average temperatures are slightly higher than during other parts of the cycle. However, the amount that the temperature rises during each day is slightly lower than typical, so the highest temperature of the day is not very much higher than usual. Hormonal contraceptives both suppress the circamensal rhythm and raise the typical body temperature by about ().

Temperature also varies with the change of seasons during each year. This pattern is called a circannual rhythm. Studies of seasonal variations have produced inconsistent results. People living in different climates may have different seasonal patterns.

Increased physical fitness increases the amount of daily variation in temperature.

With increased age, both average body temperature and the amount of daily variability in the body temperature tend to decrease. Elderly patients may have a decreased ability to generate body heat during a fever, so even a somewhat elevated temperature can indicate a serious underlying causes in geriatrics.

### Variations due to measurement methods

Different methods used for measuring temperature produce different results.

Generally, oral, rectal, gut, and core body temperatures, although slightly different, are well-correlated, with oral temperature being the lowest of the four.

Oral temperatures are influenced by drinking, chewing, smoking, and breathing with the mouth open

External fertilization

thumb|[[Stony coral]] [[spawn (biology)|spawning]].External fertilization is a form of fertilization in which a sperm cell is united with an egg cell external to the bodies of the reproducing individuals. In contrast, internal fertilization takes place inside the female after insemination through copulation.

In sexual reproduction, there must be some way of getting the sperm to the egg. Since sperm are designed to be mobile in a watery environment (they have tails and are streamlined), aquatic animals can make use of the water in which they live. Many plants make use of external fertilization, especially ones without bright flowers or other means of attracting animals. In many aquatic animals such as coral or hydra, eggs and sperm are simultaneously shed into the water, and the sperm swim through the water to fertilize the egg in a process known as broadcast fertilization. In many fish species, including salmon, the female will deposit unfertilized eggs in the substrate and the male will swim by and fertilize them. External fertilization uses or needs thousands of sperm cells

Human body

The human body is the entire structure of a humanorganism, and consists of a head, neck, torso, two arms and two legs. By the time the human reaches adulthood, the body consists of close to 100 trillioncells, the basic unit of life. These cells are organised biologically to eventually form the whole body.

## Size, type and proportion

The average height of an adult male human (in developed countries) is about 1.7â€“1.8&nbsp;m (5'7" to 5'11") tall and the adult female about 1.6â€“1.7&nbsp;m (5'2" to 5'7") tall. This size is firstly determined by genes and secondly by diet. Body type and body composition are influenced by postnatal factors such as diet and exercise.

## Systems

The organ systems of the body include the musculoskeletal system, cardiovascular system, digestive system, endocrine system, integumentary system, urinary system, lymphatic system, immune system, respiratory system, nervous system and reproductive system.

### Cardiovascular system

The cardiovascular system comprises the heart, veins, arteries and capillaries. The primary function of the heart is to circulate the blood, and through the blood, oxygen and vital minerals to the tissues and organs that comprise the body. The left side of the main organ (left ventricle and left atrium) is responsible for pumping blood to all parts of the body, while the right side (right ventricle and right atrium) pumps only to the lungs for re-oxygenation of the blood. The heart itself is divided into three layers called the endocardium, myocardium and epicardium, which vary in thickness and function.

### Digestive system

The digestive system provides the body's means of processing food and transforming nutrients into energy. The digestive system consists of the - buccal cavity, esophagus, stomach, small intestine, large intestine ending in the rectum and anus. These parts together are called the alimentary canal (digestive tract).

### Integumentary system

The integumentary system is the largest organ system in the human body, and is responsible for protecting the body from most physical and environmental factors. The largest organ in the body, is the skin. The integument also includes appendages, primarily the sweat and sebaceous glands, hair, nails and arrectores pili (tiny muscles at the root of each hair that cause goose bumps).

### Lymphatic system

The main function of the lymphatic system is to extract, transport and metabolise lymph, the fluid found in between cells. The lymphatic system is very similar to the circulatory system in terms of both its structure and its most basic function (to carry a body fluid).

### Musculoskeletal system

The human musculoskeletal system consists of the human skeleton, made by bones attached to other bones with joints, and skeletal muscle attached to the skeleton by tendons.

#### Bones

An adult human has approximately 206 distinct bones:

Spine and vertebral column (26)
Cranium (8)
Face (14)
Hyoid bone, sternum and ribs (26)
Upper extremities (70)
Lower extremities (62)

### Nervous system

The nervous system consists of cells that communicate information about an organism's surroundings and itself.

Automated external defibrillator

An automated external defibrillator or AED is a portableelectronic device that automatically diagnoses the potentially life threatening cardiac arrhythmias of ventricular fibrillation and ventricular tachycardia in a patient, and is able to treat them through defibrillation, the application of electrical therapy which stops the arrhythmia, allowing the heart to reestablish an effective rhythm.

The first AED was originally designed and created by American biomedical engineer Joshua L. Koelker and Italian emergency medical professional Jordan M. Blondino to allow defibrillation in common public places. AEDs are designed to be simple to use for the layman, and the use of AEDs is taught in many first aid, first responder, and basic life support (BLS) level CPR classes.

## Usage

### Conditions that the Device Treats

An automated external defibrillator is used in cases of life threatening cardiac arrhythmias which lead to cardiac arrest. The rhythms that the device will treat are usually limited to:

1. Pulseless Ventricular tachycardia (shortened to VT or V-Tach)
2. Ventricular fibrillation (shortened to VF or V-Fib)

In each of these two types of shockable cardiac arrhythmia, the heart is active, but in a life-threatening, dysfunctional pattern. In ventricular tachycardia, the heart beats too fast to effectively pump blood. Ultimately, ventricular tachycardia leads to ventricular fibrillation. In ventricular fibrillation, the electrical activity of the heart becomes chaotic, preventing the ventricle from effectively pumping blood. The fibrillation in the heart decreases over time, and will eventually reach asystole.

AEDs, like all defibrillators, are not designed to shock asystole ('flat line' patterns) as this will not have a positive clinical outcome. The asystolic patient only has a chance of survival if, through a combination of CPR and cardiac stimulant drugs, one of the shockable rhythms can be established, which makes it imperative for CPR to be carried out prior to the arrival of a defibrillator.

### Effect of Delayed Treatment

Uncorrected, these cardiac conditions (ventricular tachycardia, ventricular fibrillation, asystole) rapidly lead to irreversible brain damage and death. After approximately three to five minutes, irreversible brain/tissue damage may begin to occur. For every minute that a person in cardiac arrest goes without being successfully treated (by defibrillation), the chance of survival decreases by 10 percent.

### Requirements for use

AEDs are designed to be used by laypersons who ideally should have received AED training. This is in contrast to more sophisticated manual and semi-automatic defibrillators used by health professionals, which can act as a pacemaker if the heart rate is too slow (bradycardia) and perform other functions which require a skilled operator able to read electrocardiograms.

Bras with a metal underwire and piercings on the torso must be removed before using the AED on someone to avoid interference. The veracity of this comment was recently challenged when [http://dsc.discovery.com/fansites/mythbusters/db/human-body/underwire-bra-mess-with-defibrillator.html Mythbusters] found no evidence that defibrillators created problems for people wearing an underwire bra

A study analyzed the effects of having AEDs immediately present during Chicago's Heart Start program over a two year period. Of 22 individuals 18 were in a cardiac arrhythmia which AEDs can treat (Vfib or Vtach). Of these 18, 11 survived. Of these 11 patients, 6 were treated by good Samaritan bystanders with absolutely no previous training in AED use.

## Placement and Availability

Automated external defibrillators are generally either held by trained personnel who will attend events or are public access units which can be found in places including corporate and governmentoffices, shopping centres, airports, restaurants, casinos, hotels, sports stadiums, schools and universities, community centers, fitness centers, health clubs, workplaces and any other location where people may congregate.

Maimonides Medical Center in Borough Park, Brooklyn was the first hospital in the United States to implement fully automated external defibrillators at the bedside.

The location of a public access AED should take in to account where large groups of people gather, regardless of age or activity. Children as well as adults may fall victim to sudden cardiac arrest (SCA)

In many areas

Question:I need Help! Book is called: STRUCTURE AND FUCTION OF THE HUMAN BODY. MY BOOK WAS STOLEN AND I NEED HELP!? i NEED REAL HELP PLEASE MY BOOK HAS BEEN STOLEN. pLEASE NO NEGATIVITY. MY CLASS ENDS SOON. Anybpdy with the book please help. By Memmler CHApTER 17 Questions 1. The wave-like movement of the digestive tract will is called_________. 2.AThe small intestine is connecte to the posterior abdominal wall by_________. 3. the liver can store glucose in the form of_______. 4 THe parotid glands secret_______. 5. A tooth is composed mainly of a hard calcified substance called 11. The teeth break up food into small parts by a process called.....A. Absorbtion, B. Degultition, C. Ingestion, D. Mastication 12. Hydrocholoric acid and pepsinare secreted by the......A. Salivary glands,B. Stomach, C.Pancreas, D. Liver 13.The double layer of peritoneum that extends from the lower border of the stomach and hangs over the intestine is the.......A. Greater omentum, B., Lesser omentum, C. Mesentery, D. Mesocolon 14. The soft, fleshy v-shaped mass of tissue that hangs from the soft palate is the...A.Epiglottis, B.Esophageal hiatus, C.uvula, D.Gingiva 15. The entrance of the trachea is guarded during swallowing by the ........A. uvula, B.Epiglottis, C. Gingiva, D. Bolus CHAPTER 18 1. Building glycogen from glucose is an example of______. 2. The amount of energy needed to maintain life functions while at rest is_____. 3. Reserves of gluscose are strored in liver and muscle as_____ 4. Them ost important area of the brain for temperature regulation is the______. 5. Minerals needed in extremely small amounts are referred to as______> 11. During amino acid catabolism, nitrogen is removed by.....A.Oxidation, B. The glycenic effect, C. Lysis, D. Deamination 12. Which of the following would have the lowest glycenic effect?.....A. Glucose, B. Sucrose, .C. Lactose, D. Starch 13. Alcohol is catabolized by the A. Small intestine, B.Liver, C. Pancreas, D. Spleen 14. Amino acids that cannot be made by metabolism are said to be .......A. Essential B. Nonessential C. Antioxidants, D. Free radicals Chapter 19 1. Each kidney is located in the ____Space. 2. THe renal artery, renal vein, and ureter connect to the kidney at the______. 3. The ureters and urethra open at the part of the bladder called the_______. 4. The amount of dissolved substances in urine is indicated by its______. 5. Substances in the blood that prevent sharp changes in hydrogen ion concentration are called_____. 11. The functional unit of the renal system is the.....A. Renal capsule, B. Kidney, Nephron, D. Juxtaglomerular apparatus 12.Fluid moves out of the glomerulus by...A. Filtraion, B. Diffusion, C. OSmosis, D. Active transport 13. One's ability to delay urination is due to voluntary control of the....A. Trigone, B. Internal urethral sphincter, C. External urethral Spincter, D. Urinary Meatus 14. Body water contest is greatest in..A. Infatnts,B. Children, C. Young adults, D. Elderly Adults 15. Fluid located in the spaces between the cells is called......A. Cytoplasm, B. Plasma, C. Interstitial fluid, D. Lymph

Answers:the thing is....that in the time it took you to typle this you could have searched it on the web...

Question:ok.. so i need to write down one of the functions of each system in the human body and compare the function to something in real life. so i already have all the functions. i just need help with the comparing part! so here r the functions of each system if u know anything that is like it plz answer. thanx (there is a example question if u don't understand) EXAMPLE: SYSTEM : circulatory system.... FUNCTION : pumps blood to different parts of the body.removes waste. CAPMARED TO REAL LIFE: it is like a post office..it delevers goods and letters to diffferent places and its like a garbage ruck too..it picks up waste and takes it away to get rid of it.. so yea... if u understand then can u plz help... here r the rest. SYSTEM:respiratory system. FUNCTION:transports outside air to the blood , transports carbon dioxide from the blood to the outside air. SYSTEM: digestive system. FUNCTION: break down food peices into much smaller peices (particles) so they can be absorbed and transported throughout the body SYSTEM:mascular system FUNCTION:move bones, move organs that contain muscle tissue (such as the heart and stomach) SYSTEM:skeletal system. FUNCTION:prvide a movable support frame for the body, protect soft tissue organs such as the heart and lungs. SYSTEM: nervous system FUNCTION: cordinate and control the actions of all organs and organ system. detect, process, and respond to changes in external and internal environment.. SYSTEM: integumary system FUNCTION: prtect the bodies interior from external, sense pain, pressure and tepmurature lol..thats it..plz plz plz of u know ANY.. plzzz answer..i rlly need help..and i know its a lot.. but plzzzzzzzzzzzzzzzzzz help! thank you so so sooo much if u do. <333

Answers:OK: Integumentary System (Basically the skin) Like under-armor shirts, they can either warm you up or keep you cool. Like a car alarm sensor that protects the outside of your car from people scratching it, and the stuff inside from being stolen, it also helps to alert you of things going on. Nervous System:(Brain and nerves) Lets you know whats going on...and allows you to control things. such as traffic cameras letting police know when people speed and traffic lights allowing them to control the flow of traffic. To tell things to stop and other things to go. This allows communication and control, and feedback. Skeletal System. Like a TV box. It keeps your TV upright and protects it from being damaged. Muscular system: Makes everything move..like engines. it also allows you to keep your body warm and maintain homeostasis. This is where all your energy (Gas in a car/ ATP in your muscles.) is used. Digestive System: Like a donation center..this takes everything in and breaks it down/ sorts it...and then sends certian parts to the diferent people or parts of the body that need it. Respiratory System: Like Ebay I guess. It allows your cells to trade in the old CO2 that they dont need and give it to the blood. The blood then swaps it in the lungs for O2 and brings it back to the cells. The respiratory system allows this trade to take place, and is like a gas market place.

Question:this question is related to human resource management and it deals with need of employee in any organization.