In this work, ZnO nanostructures for powder ZnO were synthesized by Hydrothermal Method. Size and shape of ZnO nanostructureas can be controlled by change ammonia concentration. In the preparation of ZnO nanostructure, zinc nitrate hexahydrate [Zn(NO₃)₂·6H2O] was used as a precursor. The structure and morphology of ZnO nanostructure have been characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD). The synthesized ZnO nanostructures have a hexagonal wurtzite structure. Also using Zeta potential and Particle Size Analyzers and size distribution of the ZnO powder

The present study showed that the branchial arch is characterized by the presence of
irregular black line along its length. This line is condensations of melanocytes . The branchial
arch bears two rows of gill rakers at its anterior (internal) side whereas its posterior (external)
side bears two rows of gill filaments. Histologically, the gill arch is composed of hyaline
cartilage surrounded by mixed bone ,which is covered by a mucous membrane. Its epithelium
contains mucous cells and taste buds, whereas its loose connective tissue contains blood
vessels and skeletal muscles. The histological structure of gill raker is similar to that of the
gill arch except the absence of cartilage and muscles .The present st

   The present study aimed to investigate the morphological description and histological structure of kidney in adult albino mice (Mus musculus), The anatomical study revealed that the kidney in albino mice is represented by bean-like shape, smooth with red to brown color, It is situated within the anterior half of abdominal cavity under the diaphragm on both sides of vertebral column. The kidney is covered by capsule of loose connective tissue with mean thickness of (9.6±0.5) micrometer. Histological examination revealed that albino mice kidney tissue differentiated into cortex and medulla, the cortex contains glomeruli with mean diameter of (50.5±1.9) micrometer densely distributed at the peripheral area of the cortex ,

The Tamarix aphylla is a wild perennial shrub with erect stems that are long and glabrous. They have leaves that are simple, alternate, sheathed, and the apex of the blade is acuminate. And a scaly clawed bract and the the inflorescences were simple, spike-like. The pistil consists of ovary pyramidal, 3 styles, and 3 stigmas. The androecium consists of five stamens that are antisepalous. The perianth was distinct with five sepals and five petals. The fruits were capsule-shaped, pyramidal, and smooth. The seed has an apical pappus of unicellular hygroscopic hairs; endosperm is absent. The anatomical study of the leaves contained a uniseriate epidermis consisting of one layer of elongated cells covered by a layer of papillary cuti

The current study included a detail morphological study of all parts of the species Ipomoea carnea Jacq. (Convolvulaceae) cultivated in different gardens, the roots, stems, leaves, flowers and fruit were studied in detail, also the pollen grains were studied and there are photographs for all the parts were putted.

  A histological study was conducted to examine the structure of optic tectum in Hemidactylus flaviviridis. The results showed that the optic tectum consists of fourteen strata organized in three zones. The deep zone which extends from the first stratum (around optic ventricle) to the fifth stratum. The medium zone comprises the sixth & seventh strata, which represent the center of optic tectum. The superficial zone which extends from the eighth stratum to the fourteenth stratum and forms the retino recipient region.         The strata of deep zone are called the Stratum Griseum et Periventricular ( SGAP ) , the sixth stratum  is  called the Stratum Album Central ( SAC ) and&nbsp