Bone marrow is soft, spongy, gelatinous tissue that fills the centers of bones known as medullary cavities. Bone marrow is highly vascular meaning that it is enriched with blood vessels and capillaries. Each day bone marrow produces hundreds of billions of new blood cells. Bone marrow takes over from the liver as the major hematopoietic organ […]
Basics
Electron microscope – Uses, Advantages and Disadvantages
An electron microscope is a type of microscope that uses an electron beam for illumination and creates an enlarged image of the specimen. (In contrast, light microscope uses visible light for purpose of illumination). An electron microscope has great resolving power and can create much higher magnification as compared to a light microscope. Hence it […]
Circle of Willis Anatomy and Function
The circle of Willis is a polygon-shaped arterial anastomosis in the brain formed by internal carotid and vertebral artery systems around the optic chiasm and infundibulum of the pituitary stalk in the suprasellar cistern. It is also known by names of circulus arteriosus cerebri, Willis’ circle, loop of Willis, cerebral arterial circle, and Willis polygon […]
Penis Anatomy, Function, Blood and Nerve Supply
The penis is an external organ of the male reproductive system. It has two main functions. It acts as the intromittent organ that also serves as urinal duct. An intromittent organ is a general term for an external organ of a male organism that is specialized to deliver sperm during copulation For sexual intercourse, the penis undergoes erection during erotic stimulation and becomes […]
Human Chorionic Gonadotropin – Structure, Function, Test and Uses
Human chorionic gonadotropin (hCG) is a hormone produced during pregnancy by the placenta. It provides nourishment to the egg after it has been fertilized and attached to the uterine wall. HCG is used to detect pregnancy as well as to monitor it. It is also elevated in certain cancers, hence is used as a tumor […]
Hypodermoclysis or Subcutaenous Infusion – Indications, Method and Uses
Subcutaneous infusion, or hypodermoclysis, is a method in which fluids are infused into the subcutaneous space via small-gauge needles. Clysis means the introduction of large amounts of fluid into the body usually by parenteral injection to replace that lost. So hypodermoclysis means via subcutaneous tissue and phleboclysis means via the vein. After the fluid is […]
Great Saphenous Vein and Lesser Saphenous Vein Anatomy
Great saphenous vein and small saphenous veins are veins of the lower limb. The great saphenous vein is the longest vein in the body that originates near medial malleolus and goes up to the level of groin skin crease. blood from the foot, leg, and thigh to the deep femoral vein at the femoral triangle. It […]
Bezold Jarisch reflex
The Bezold-Jarisch reflex is a parasympathetic inhibitory reflex induced stimulation of mechanoreceptors in the heart, chemical or mechanical leading to leading to bradycardia, shallow respiration or low respiratory rate, vasodilation, and hypotension. Bezold Jarisch reflex is thought to be the basis of some unusual reactions where hyper stimulation of the myocardium paradoxically leads to profound […]
Antiseptics and Disinfectants – Types and Uses
Antiseptics and disinfectants are nonselective, anti-infective agents that are applied topically. In general, antiseptics are applied on tissues to suppress or prevent microbial infection. Disinfectants are germicidal compounds usually applied to inanimate surfaces. Both can be covered by more general term, biocide. Sometimes the same compound may act as an antiseptic and a disinfectant, depending […]
Fluorescent In Situ Hybridization or FISH Test
Fluorescent in situ hybridization (FISH) is a molecular cytogenetic technique used for the detection and localization of chromosomal sequences within tissues or cells. In this technique, fluorescent probes are used which bind to complementary chromosomal sequences, which can be visualized using a fluorescent microscope. It helps to visualize and map the genetic material in an individual […]