Journal of Morphology

General scheme of the cartilage anlage shape modulation during early growth: a level-headed, eccentrical chondrocyte proliferation led to the globular shape of short bone anlage (a), while a prevailing, axial proliferation to the elongated shape of long bone anlage (b). Assessment of morphometric parameters and intralacunar, paired chondrocytes was used in the paper to give evidence of intralacunar polarization during fetal development before metaphyseal growth plate frame organization.

Ontogenetic changes in eye development of Pleurodema bufoninum and Pleurodema somuncurense. Asterisks: since the timing differences found in both species could be probably due to the different environment of precedence as we mentioned above they were not taken into account in this summary.

Number and size of spermathecae are larger in species that exhibit overlapping broods (superfetation).

Functional morphology of the female reproductive system of a crab with highly extensible seminal receptacles

Primary feather emargination (E) covaries with mass and habitat type among 135 avian species. Pelagic species have very little or no emargination, suggesting they are under different aerodynamic selective pressures than terrestrial and coastal/freshwater species.

The dorsal hump morphologies were analyzed in four Pacific salmon species, masu (Oncorhynchus masou), sockeye (O. nerka), chum (O. keta), and pink salmon (O. gorbuscha). Analysis of dorsal hump shapes demonstrated that sockeye and pink salmon developed more pronounced dorsal humps than masu and chum salmon. The internal structure of the dorsal humps also depended on the species; sockeye and pink salmon showed conspicuous development of connective tissue and growth of bone tissues in the dorsal tissues. On the other hand, masu and chum salmon exhibited less-pronounced increases in connective tissues and bone growth.

Anatomical networks formalize the topological arrangement of parts of morphological systems. Network models can be used to identify and delimit biologically meaningful morphological modules.

In this study, the morphological characteristics of atrioventricular conduction system (AVCS) and Purkinje fibers of yak were observed through different methods for the first time. Light and transmission electron microscopy were used to study the histological features of AVCS, including the cellular component of atrioventricular node (AVN), His-bundle, the left bundle branch (LBB), right bundle branch (RBB). The distributional characteristics of the His-bundle, LBB, RBB, and Purkinje fiber network of yak hearts were examined using gross dissection, ink injection and ABS casting. The results showed that the AVN of yak was composed of the slender, interweaving cells formed almost entirely of the transitional cells (T-cells), and few pacemaking cells (P-cells). The His-bundle extended from the AVN, and split into left LBB and RBB at the crest of the interventricular septum. The LBB descended along the left side of interventricular septum. At approximately the upper 1/3 of the interventricular septum, the LBB typically divided into three branches. The RBB ran under the endocardium of the right side of interventricular septum, and extended to the base of septal papillary muscle, passed into the moderator band, crossed the right ventricular cavity to reach the base of anterior papillary muscle, and divided into four fascicles under the subendocardial layer. The Purkinje fibers in the ventricle formed a complex spatial network.

The electron microscopic analysis revealed that there are similarities but also major differences in the ultrastructural organization of adult and larval neuromuscular junctions in Drosophila melanogaster.

The coelomic lining of Lingula anatina is organized in several ways: it is formed by myoepithelium, by alternating epithelial and muscle cells, and by coelothelium. Different kinds of junctions coordinate the functioning of epithelial and muscle cells.

A type of organization of coelomic lining in Lingula anatina: two types of cells and several kinds of cell junctions are shown.