Posts

Comparison between tract and nerve

-
  Comparison between tract and nerve Nerve Nerve contain bundle of axons (nerve fibers) in the peripheral nervous system (PNS) that transmits signals between the central nervous system (CNS) and other parts of the body. It is the most important part of peripheral nervous system Location: Peripheral nervous system. Structure: Made of axons, connective tissue layers (endoneurium: axon is surrounded by it , perineurium: bundle of axons are surrounded by it, epineurium: whole nerve trunk is surrounded by it), and blood vessels. It gets myelination by Schwann cell   Function: Carries sensory signals to the CNS (afferent) from peripheral part of body or motor signals carry from from the CNS (efferent) to target organs like skeletal muscle, cardiac muscle, smooth muscle or glands Example: Sciatic nerve, median nerve, except optic nerve (though optic nerve is technically part of CNS in develop...
Post a Comment
Read more

Difference between CT angiography and MR angiography

-
CT Angiography (CTA) vs. MR Angiography (MRA) CT angiography (CTA) and MR angiography (MRA) are advanced imaging techniques used to visualize blood vessels of body . They are commonly used for detecting vascular diseases , like aneurysms , stenosis , duplication   and vascular malformations . 1. CT Angiography (CTA) Principle: it u ses X-rays and computerized tomography (CT) to create detailed 3D images of blood vessels which requires an iodinated contrast agent injected intravenously and it has fast acquisition time. Advantages of CT angiography: It generates h igh-resolution images (better visualization of small vessels) and scan time is faster usually within a few seconds. Any calcified plaques in arteries is better diagnosis by this process (e.g., coronary arteries). This procedure can done in emergency settings (e.g., stroke, pulmonary embolism). Disadvantages: it is not ideal for repetitive imaging because it u ses ionizing radiation (not ideal for frequ...
Post a Comment
Read more

Difference between granular and agranular leukocytes

-
Image
Difference between granular and agranular leukocytes Leukocytes or white blood cells are divided into two main types according to the presence or absence of granules in their cytoplasm: 1. Granular Leukocytes These leukocytes contain visible granules in their cytoplasm and have a lobed nucleus. They include: Neutrophils (Most abundant, 50-70% of WBCs). It phagocytosis of bacteria and fungi. It has multilobed nucleus, fine granules. It is neutral (pinkish stain in H&E). Eosinophils (1-4% of WBCs)  it defend against parasitic infections, modulate allergic reactions.it has bilobed nucleus, large red/orange granules. Stain: Acidic (eosinophilic, red/orange). Basophils (Least abundant, <1% of WBCs) release histamine and mediate inflammatory and allergic responses. It has bilobed nucleus, large dark blue/purple granules. Stain: Basic (basophilic, blue/purple). 2. Agranular Leukocytes (Agranu...
Post a Comment
Read more

Difference between parotid and submandibular gland

-
Image
  Difference between parotid and submandibular gland Histology of Parotid Gland Type: Purely serous gland : produces watery like secretion which  rich in enzymes Histological Features: Capsule & Septa : parotid gland is surrounded by a fibrous capsule , which extends into the gland forming septa , dividing it into lobules . The Secretory Units of parotid gland is composed entirely of serous acini which is  d arkly stained, pyramidal-shaped cells with round nuclei , and basophilic cytoplasm due to rough endoplasmic reticulum (RER). It secrete amylase (digestion of carbohydrates) and antimicrobial proteins (lysozyme, lactoferrin). Duct System of parotid gland : types of ducts Intercalated ducts : it is lined by simple cuboidal epithelium. Striated ducts : it is larger, lined by simple columnar epithelium , and have basal striations due to mitochondri...
Post a Comment
Read more