Development and Structure of the Thymus

Abstract

The thymus is the first lymphoid organ of embryonic life in mammals. It reaches its maximum relative weight (15 grams) at the end of fetal life. After birth, it continues to develop and its absolute weight reaches 30-40 grams. The source of the thymus is the endodermal diverticula that extend from the ventral side of the third pharyngeal pouch, on both sides of the midline, to the thoracic region. A part of the fourth pharyngeal pouch also joins the thymus structure.

Keywords

• thymus
• embyonic
• absolute weight

Timusun Gelişimi ve Yapısı

Abstract

Timus memelilerde embriyoner hayatın ilk lenfoid organıdır. Fötal hayatın sonunda maksimal relatif ağırlığına ulaşır (15 gr.). Doğumdan sonra gelişmesine devam ederek absalü ağırlığı 30-40 gramı bulur, Timusun kaynağı üçüncü yutak kesesinin ventralinden, orta çizginin iki yanından, dışa, toraks bölgesine doğeunan endodermal divertiküllerdir. Dördüncü yutak kesesinin bir bölümü de timus yapısına katılır.

Keywords

• timus
• mutlak ağırlık
• embiryonik

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