Yurak: Versiyalar orasidagi farq

Kontent oʻchirildi Kontent qoʻshildi
yangi
 
kTahrir izohi yoʻq
Qator 1:
[[File:Anatomy Heart English Tiesworks.jpg|thumb|right|[[Odam]] yuragi.]]
'''Yurak''' takroriy ritmik qisqarishlar orqali [[qon]]ni [[tomir]]larda yurgizuvchi [[organ (anatomiya)|organdir]]. Yurak [[qon aylanish tizimi]]ga ega barcha [[hayvon]]larda mavjud.
 
The vertebrate heart is principally composed of [[cardiac muscle]] and [[connective tissue]]. Cardiac muscle is an involuntary striated muscle tissue found only in this organ and responsible for the ability of the heart to pump blood. The average [[human heart]], beating at 72 beats per minute, will beat approximately 2.5 billion times during an average 66 year lifespan. It weighs approximately {{convert|250|to|300|g|oz|0}} in females and {{convert|300|to|350|g|oz|0}} in males.<ref>Kumar, Abbas, Fausto: ''Robbins and Cotran Pathologic Basis of Disease'', 7th Ed. p. 556</ref>
 
In [[invertebrate]]s that possess a circulatory system, the heart is typically a tube or small sac and pumps fluid that contains water and nutrients such as [[protein]]s, [[fat]]s, and [[sugar]]s. In [[insect]]s, the "heart" is often called the '''dorsal tube''' and insect "blood" is almost always not oxygenated since they usually [[Respiration (physiology)|respirate]] (breathe) directly from their body surfaces (internal and external) to air. However, the hearts of some other [[arthropod]]s (including [[spiders]] and [[crustacean]]s such as [[crab]]s and [[shrimp]]) and some other animals pump [[hemolymph]], which contains the [[copper]]-based protein [[hemocyanin]] as an oxygen transporter similar to the [[iron]]-based [[hemoglobin]] in [[red blood cells]] found in [[vertebrates]].