Larval development of the shell and the shell gland inMytilus (Bivalvia)
1Lehrstuhl für Zellmorphologie, Ruhruniversität Bochum, Germany.
Wilhelm Roux'S Archives of Developmental Biology
|March 18, 2017
Abstract:
In the newly hatched larva ofMytilus galloprovincialis the larval shell field almost totally invaginates to form a shell gland. Only very few cells remain outside and they meet at one point. Only these cells secrete the pellicle, which in the beginning is protected by the glycocalyx and the microvilli of the surrounding cells. The invaginated cells do not participate in pellicle secretion. The secretion partly passes through infoldings of the apical cell membrane. Mineralization of each valve begins along the hinge line, continues to the valve margins and includes the valve centre.
More Related Videos
Related Concept Videos
01:15Development of the Lymphatic System
2.4K
The development of lymphatic tissues and vessels in embryonic life begins around the fifth week. These structures originate from the mesoderm layer, with lymph sacs emerging from developing veins.
The first lymph sacs to form are the paired jugular lymph sacs located at the junction of the internal jugular and subclavian veins. From these sacs, lymphatic capillary plexuses extend to the thorax, upper limbs, neck, and head, eventually forming lymphatic vessels. Each jugular lymph sac maintains a...
The first lymph sacs to form are the paired jugular lymph sacs located at the junction of the internal jugular and subclavian veins. From these sacs, lymphatic capillary plexuses extend to the thorax, upper limbs, neck, and head, eventually forming lymphatic vessels. Each jugular lymph sac maintains a...
2.4K
01:56Gastrulation
68.2K
Gastrulation establishes the three primary tissues of an embryo: the ectoderm, mesoderm, and endoderm. This developmental process relies on a series of intricate cellular movements, which in humans transforms a flat, “bilaminar disc” composed of two cell sheets into a three-tiered structure. In the resulting embryo, the endoderm serves as the bottom layer, and stacked directly above it is the intermediate mesoderm, and then the uppermost ectoderm. Respectively, these tissue strata...
68.2K