The Placenta
The Placenta: The placenta connects the developing fetus to the uterine wall, allowing nutrient and gas exchange, hormone production, and waste removal through the umbilical cord.
Category Archives: Organs
Summary of Factors in Cardiac Output
Summary of Factors in Cardiac Output: Cardiac output is influenced by heart rate and stroke volume, which are in turn affected by factors such as autonomic nervous system input, blood volume, and myocardial contractility.
Stomach
Stomach: The stomach is a muscular, J-shaped organ that secretes acid and enzymes to digest food mechanically and chemically, preparing it for absorption in the small intestine.
Structures of the Respiratory Zone
Structures of the Respiratory Zone: The respiratory zone includes respiratory bronchioles, alveolar ducts, and alveolithin-walled structures where gas exchange between air and blood takes place.
Salivary Glands
Salivary Glands: The major salivary glandsparotid, submandibular, and sublingualsecrete saliva containing enzymes like amylase to begin starch digestion and lubricate food for swallowing.
Pharynx
Pharynx: The pharynx is a muscular tube behind the nasal and oral cavities that conducts air to the larynx and food to the esophagus.
Heart Valves
Heart Valves: The hearts four valvestricuspid, pulmonary, mitral, and aorticmaintain unidirectional blood flow and prevent backflow during the cardiac cycle through coordinated opening and closing.
Ureter
Ureter: The ureters are muscular tubes that transport urine from the kidneys to the bladder using peristaltic contractions and gravity.
The Lung Pleurea
The Lung Pleurae: The lungs are enclosed by the pleuraetwo thin layers of serous membrane (visceral and parietal) separated by pleural fluidwhich reduce friction during breathing and help maintain lung expansion.
The Posterior Pituitary Complex
The Posterior Pituitary Complex: The posterior pituitary stores and releases oxytocin and antidiuretic hormone (ADH), both produced in the hypothalamus, affecting uterine contractions and water reabsorption in the kidneys, respectively.
The Location Structure and Histology of the Thymus
The Location Structure and Histology of the Thymus: The thymus is located in the anterior mediastinum, made of lobules containing cortex and medulla, and supports T cell maturation, especially in childhood.
Gallbladder
Gallbladder: The gallbladder stores and concentrates bile produced by the liver, releasing it into the small intestine to aid in the digestion and absorption of fats.
Bone Marrow
Bone Marrow: Bone marrow is the primary site of blood cell production, including red and white blood cells and platelets, and contains stem cells that support hematopoiesis.
Gross Anatomy of the Lungs
Gross Anatomy of the Lungs: Each lung has lobes (three on the right, two on the left), a hilum for vessel entry/exit, and surfaces that fit into the thoracic cavity, facilitating gas exchange.
Internal Anatomy of the Heart
Internal Anatomy of the Heart: The heart consists of four chamberstwo atria and two ventriclesalong with valves (tricuspid, mitral, pulmonary, and aortic) that ensure unidirectional blood flow through the cardiac cycle.
Spleen
Spleen: The spleen filters blood, removes old red blood cells, stores platelets, and plays a key role in the immune response by housing lymphocytes and macrophages.
The Adrenal Glands
The Adrenal Glands: The adrenal glands sit atop each kidney and consist of an outer cortex (producing cortisol, aldosterone, and androgens) and an inner medulla (secreting adrenaline and noradrenaline).
Male Urethra
Male Urethra: The male urethra is a dual-purpose tube that conveys urine and semen; it passes through the prostate, urogenital diaphragm, and penis in prostatic, membranous, and spongy sections.
Teniae Coli Haustra Epiploic Appendage
Teniae Coli Haustra Epiploic Appendage: These large intestine structures include teniae coli (longitudinal muscle bands), haustra (pouches), and epiploic appendages (fat-filled sacs), all contributing to motility and structure.
The Parathyroid Glands
The Parathyroid Glands: The parathyroid glands are small endocrine glands on the posterior thyroid that regulate calcium levels by secreting PTH in response to low blood calcium.