وفر 50٪ من خلال الاشتراك السنوي في مجرة واحصل على تصفح لا محدود لأفضل محتوى عربي على الإنترنت.

اشترك الآن

تمت عملية الاشتراك بنجاح

إغلاق

عذراً، عذرا،أنت مشترك مسبقاً بالنشرة البريدية

إغلاق

عذراً، هناك مشكلة في البريد الالكتروني

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الطب

الشعر عند الثدييات |  Hair in mammals

26 أبريل 2020


خيوط مصنوعة من نوع معين من البروتينات؛ وهي الكرياتين، تنمو من انقسام الخلايا في جريب الشعر في الجلد، ولها وظائف الحماية من البرد، والحفاظ على حرارة الجسم، والتمويه، والزينة للانتقاء الجنسي عند الحيوانات.