ZOOLAB HISTOLOGY (2)

• Tunica serosa – Outermost covering of the digestive tube, covered by squamous epithelium, thin layer of loose connective tissue
• Tunica Muscularis: Layer of smooth muscles
• Stratum Longitudinale: Outer layer of longitudinal muscle fibers
• Stratum Circulare: Thicker inner circular layer of muscle fibers
• Tela Submucosa: Layer of connective tissue with blood vessels and nerves
• Contains goblet cells secreting intestinal juice for digestion
• Stomach: A muscular organ that digests food by contracting and producing acids and enzymes that break down food which will pass to the intestine
• Tunic Subserosa: Occupies space between tunica serosa and muscularis, Composite structure with connective tissues and longitudinal muscle fibers, composed of blood vessels, lymphatics, nerves, connective tissue elements, and longitudinal muscle fibers
• Muscularis Mucosa: Found within the innermost submucosal layer, Involved in peristaltic contractions for mechanical breakdown of ingested material
• Tunica Propia: Located between muscularis mucosa and tunica mucosa, Provides structural support to gastric glands responsible for secreting digestive enzymes
• Liver: Largest gland of the body secreting bile, an emulsifier for fat digestion. It is made up of many polygonal cells called the liver cells separated by spaces, the blood capillaries or sinusoids
• Blood Vessels: Channels for nutrient-rich blood.
• Bile Duct: Smaller duct lined with cuboidal cells
• Arterioles: : Regulate blood flow within the organ.
• Bile Capillary: Characterized by fewer cuboidal cells, Involved in the transport of bile
• Kidney: primary excretory organ responsible for the elimination of excess and unnecessary substances from an organism’s body fluids
• Mesonephric duct: lumen lined with epithelial cells and the renal portal vein with red blood cell, crucial for the embryonic development of the kidney system in both sexes
• Uriniferous tubules - lined with cuboidal cells
• Bowman’s capsules - contain blood capillaries, the glomerulus
• Top portion of kidney - composed of adrenal glands which produce different types of hormones as androsterone, cortisone, and adrenalin.
• Ovary: Female sex gland which is a sac-like structure containing egg cells.
• Male gonad: Composed of seminiferous tubules
• Outer Visceral Peritoneum: covers • seminiferous tubules
• Tunica Albuginea: covers seminiferous tubules alongside outer visceral peritoneum
• Seminiferous tubules - houses blood vessels, nerves, and interstitial cells called the cells of Leydig.
• Interstitial Cells: produces sperm cells and sex hormones
• Mesorchium: mesentery of organ; contains blood vessels and vasa efferentia (kidney tubules)
• Spinal Cord: Connects brain to lower back. spinal cord carries nerve signals from brain to body and vice versa
• Central Canal (Canalis Centralis): It is the central cavity of the organ lined with columnar cells called ependymal cells.
• White Matter: Outer portion
• Gray Matter: inner mass with nerve cells and neuroglia cells or supportive cells. Its lateral slender extensions are the dorsal horns, while the broad extensions are composed of stellate motor cells.
• Dura Matter: Outer Portion
• Pia Matter: inner portion
• Ventral Septum: It is the ventral fissure of the broader ventral surface with blood vessels, the ventral spinal artery
• Dorsal Septum: It is the dorsal fissure of the narrower dorsal surface.