برزنتيشن عن body language
برزنتيشن عن لغة الجسد
بالانجليزي
برجراف عن الجسم
برجراف عن your body بالانجليزي
short presentation about body language
برجراف عن جسم الانسان
بالانجليزي
body language presentation powerpoint
موضوع عن جسم الانسان بالانجليزي
مقدمة عن لغة الجسد
موضوع عن جسم الانسان بالانجليزي
برجراف عن جسم الانسان
بالانجليزي
برجراف عن الجسم بالانجليزي
اعضاء الجسم الداخلية بالانجليزي
اعضاء الجسم بالانجليزي
مترجم بالعربي
اعضاء الجسم بالانجليزي
للاطفال
اسماء اعضاء الجسم بالانجليزي
بالصور
اعضاء جسم الانسان التناسلية
بالانجليزية
اجزاء جسم الانسان بالتفصيل
برجراف عن الجسم بالانجليزي
موضوع عن صحة الجسم بالانجليزي
اعضاء الجسم الداخلية بالانجليزي
اعضاء الجسم بالانجليزي
مترجم بالعربي
اعضاء الجسم بالانجليزي
للاطفال
اسماء اعضاء الجسم بالانجليزي
بالصور
اسماء اعضاء الجسم الداخلية
والخارجية بالانجليزي
اعضاء جسم الانسان التناسلية
بالانجليزية
اجزاء الوجه بالانجليزي
اجزاء الجسم بالانجليزي
للاطفال
اجزاء جسم الانسان بالصور
للاطفال
اجزاء جسم الانسان بالتفصيل
اسماء اعضاء الجسم كاملة
اجهزة جسم الانسان بالانجليزي
The human body is the cultural and physical structure of the body of a
human being. The human body consists of several systems and more than 600
muscles and more than 200 bones.
Definitions
An organ is a structural and functional entity composed of different
tissues endowed with complementary capacities and performing a specific
function but having meaning only within a system.
conventions
To make the description comprehensible, anatomy must set out a number of
conventions:
• The reference position is
that of the standing subject, whose upper limbs hang down the body with the
palms facing forward. Thus the notions of superior, inferior, anterior and
posterior become the same for all.
• There is still a need to
develop orientation plans:
• the frontal plane is a
vertical plane parallel to the front;
• the median sagittal plane
is a vertical plane that passes through the sternum and spine. It divides the
body into two symmetrical parts. The other sagittal planes are parallel to the
median sagittal plane. An anatomical structure is called external when it moves
away from the median and internal plane when it approaches it;
• the transverse plane is a
horizontal plane perpendicular to the vertebral column.
• The position of a structure
along a limb is defined by the terms proximal (near the root of the limb) and
distal (away from the root of the limb). The position of a structure located
near the skin is called superficial. It is described as deep when the structure
considered is located away from the skin.
Life of different human cells
This section is empty, insufficiently detailed or incomplete. Your help
is welcome!
In 2005, a team from the Karolinska Institute in Stockholm measured the
age of human cell groups, based on the amount of carbon 14 present in the DNA.
The conclusions of the report are that:
• The lifetimes of cell types
are very variable, such as 2 weeks for epidermal cells, 4 months for red blood
cells, a few hours for cells in the intestine wall, while the other intestinal
cells have a duration of average life of 16 years, or the cells of the cortex
that would have the age of the individual11,12. It is the cornea of the eye that has the shortest life span, and
therefore renews itself the fastest, in any mammal, including man (within 7
days maximum).
• The various factors
responsible for natural aging are complex to identify; certain elements are
nevertheless considered as being able to determine with more or less accuracy
the process of degradation of the human body. Among these, the action of free
radicals on the cells can be identified. These are oxidizing substances
produced by a normal metabolism. These include the superoxide anion (O2-),
hydrogen peroxide (H2O2) and the hydroxyl radical (.OH) 13,14. It should be
emphasized that these naturally occurring substances also occur when a person
is exposed to radioactive radiation, and that they are mutagenic, that is, capable
of causing cancer.
• Aging is a process of
oxidation of body cells, whose regeneration cycles are estimated to last
approximately 60 years. Medicine, or progress in hygiene, has made it possible
to prolong life expectancy, by slowing down the oxidation of cells15.
Thus, the adaptability of cells with the environment in which they
operate is considered to be a major factor influencing life expectancy.
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