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The human skeleton
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The human skeleton

In addition to supporting the body, the skeleton protects the internal organs and provides support points for muscle attachment. It consists of bone parts (in all 208 bones in the adult individual) and articulated cartilaginous bones, which form a system of levers moved by the muscles. The human skeleton can be divided into two parts: Axial skeleton: formed by the cranial box, spine thoracic box (in yellow).

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Lamarck's ideas

French naturalist Lamarck was the first to propose a synthetic theory of evolution. His theory was published in 1809 in the book Zoological Philosophy. He said that simpler life forms arise from inanimate matter by spontaneous generation and progress to a stage of greater complexity and perfection.
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Cardiac movements: systole and diastole

Ventricular contraction is known as systole and ventricular emptying occurs in it. Ventricular relaxation is known as diastole and it is at this stage that the ventricles receive blood from the atria. Ventricular contraction then forces blood to the pulmonary and aorta arteries, whose semilunar valves (three half-moon membranes) open to allow blood to pass through.
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Gemini Formation

Twins are called two or more siblings born in a multiple birth, that is, from the same gestation of the mother, and may be identical or not. By extension, children born from triple, quadruple or more births are also called twins. Although there is no precise statistics, it is estimated that one in 85 pregnancies is twin.
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Digestion Problems

Indigestion is a disturbance of digestive functions. It is very difficult to find a person who has never had indigestion, and for most people it is just a passing annoyance. However, for some people the symptoms of indigestion can be so severe that they interfere with daily activity, impairing quality of life.
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Trace organs

Trace organs are atrophied structures with no obvious function in the body. The cecal appendix of the human intestine, for example, is a vestigial organ. This organ is a small projection of the caecum (region of the large intestine) and plays no important role in man and carnivorous animals. In herbivores, however, the appendix is ​​very developed and plays an important role in cellulose digestion; in it live microorganisms that act on the digestion of this substance.
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The excretion in humans

The main product of nitrogen excretion in humans is urea. It is synthesized in the liver from ammonia in a series of chemical reactions known as the urea cycle. The excretions produced in our metabolism are eliminated by various organs, including the skin, lungs and especially the kidneys.
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Problems related to excretion

Dehydration is a deficiency of water in the body. Dehydration occurs when water is eliminated from the body more than the volume ingested. Water deficiency generally causes an increase in the concentration of sodium in the blood. Vomiting, diarrhea, the use of diuretics (medicines that excrete excessive amounts of salt and water in the kidneys), excessive heat, fever and a decrease in water consumption can lead to dehydration.
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Sperm

Sperm are usually cells, much smaller than eggs, and are structured to allow maximum displacement efficiency, which increases their chance of reaching the egg. They are small, elongated, hydrodynamically shaped cells with a long tail that is used for propulsion.
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Chemical mediators in sympathetic and parasympathetic SNPA

In both sympathetic and parasympathetic SNPA ganglia, chemical synapses occur between the pre-ganglion and post-ganglion neurons. In both cases, the neurotransmitter substance of the synapse is acetylcholine. In the terminations of postglandionary neurons, which synapse with the effector organs, however, the neurotransmitter substance is not the same for the two branches of SNPA.
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Degenerative disorders of the nervous system

Several factors can cause cell death and more or lesser degeneration of the nervous system. These factors may be gene mutations, viral infections, psychotropic drugs, metal poisoning, etc. The best known degenerative nerve diseases are multiple sclerosis, Parkinson's disease, Huntington's disease and Alzeheimer disease.
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Hormonal regulation

The endocrine system is formed by the set of endocrine glands, which are responsible for the secretion of substances called generically hormones. The endocrine glands (Greek endos, inside, and krinos, secretion) are so-called because they release their secretion (hormones) directly into the blood or hemolymph, as distinguished from exocrine glands (Greek exos, outside), which release its secretions out of the body or into the hollows of hollow organs.
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Tracheal Breathing

Several terrestrial arthropods, such as insects, kilopods, diplopods, some ticks and some spiders, breathe through trachea. The tracheas of insects are very thin conductive tubules. They originate from tiny holes, the spiracles, located in the lateral regions of the chest and abdomen and end in the cells.
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Reflex arc

No other fabric illustrates the concept of teamwork as well as nervous tissue. The transmission of information by nerve cells resembles a true relay race, in which one neuron is connected to another, each playing a role in the circuit they organize.
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Pulmonary Embolism

Is The sudden closure of the pulmonary artery or one of its branches, caused by air bubbles, tumor fragments, or often blood clots. The closure of a small artery may go unnoticed, but if a large artery is struck, the person experiences sudden chest pain, shortness of breath, increased sweating, palpitations, cyanosis, and eventually death.
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Respiratory System Disorders

Sinusitis is an inflammation of cavities in the bones of the face, sinus or sinus. These cavities have communication with the nasal passages and can be invaded by bacteria, which trigger an infectious process. In acute sinusitis, the person has pain in various regions of the face and there is mucous and sometimes purulent nasal discharge (with pus).
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Appendicular Skeleton

Joints and Waists Each upper limb is made up of the arm, forearm, wrist and hand. The arm bone - humerus - articulates at the elbow with the bones of the forearm: radius and ulna. The wrist consists of small, massive bones, the carpus. The palm is formed by the metacarpals and the fingers by the phalanges.
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Spine

It is a column of vertebrae that each have a hole, which overlap each other forming a channel that houses the nerve or spinal cord. It is divided into typical regions which are: cervical spine l (neck region), thoracic spine, lumbar spine, sacral spine, coccyclic spine (coccix). Rib Cage It is formed by the thoracic region of the spine, external bone and ribs, which are number 12 on each side, the first 7 being true (inserted directly into the sternum), 3 false (joining and then joining the sternum) ), and 2 floating (with free anterior ends, not attaching to the sternum).
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The human skeleton

In addition to supporting the body, the skeleton protects the internal organs and provides support points for muscle attachment. It consists of bone parts (in all 208 bones in the adult individual) and articulated cartilaginous bones, which form a system of levers moved by the muscles. The human skeleton can be divided into two parts: Axial skeleton: formed by the cranial box, spine thoracic box (in yellow).
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Complementary gene action

Bateson and Punnet's pea flower color described another case of gene interaction by analyzing flower color inheritance in pea plants. The flowers on these plants may be white or purple in color. Crossing two white flowering plants of different origins, they obtained in F 1 only purple flowering plants.
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Turner Syndrome (XO)

It is a monosomy in which affected individuals exhibit female sex but generally do not have sexual chromatin. Examination of its karyotype commonly reveals 45 chromosomes, and of the pair of sex chromosomes there is only one X; We say that these individuals are XO (x-zero), and their karyotype is represented by 45 X.
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