Topic 2 - Embryology, Normal range and Congenital 8556fc1d36694005873f8a132b97b833.pdf

🧠 Topic 2 - Embryology, Normal range and Congenital Problems Cell → Tissue → Organ → System Define tissue A collection of cells that are adapted to perform a specific function...

🧠 Topic 2 - Embryology, Normal range and Congenital Problems Cell → Tissue → Organ → System Define tissue A collection of cells that are adapted to perform a specific function Define organ Two or more tissues combined to create a structural unit that has a particular function. Epithelial Tissue covers body surface, forms lining for internal cavities provides protection, secretion, absoprtion & filtration contains basement membrane found in liver, kidney, skin, lung Connective Tissue used for support + protection of organs + cells Topic 2 - Embryology, Normal range and Congenital Problems 1  transporting nutrients and wastes, defending against pathogens, storing fat, and repairing damaged tissues. examples: cartilage, bone, blood, tendon, ligament What are the 3 divisions of muscular tissue? Skeletal - used in contraction of skeletal parts Smooth - walls of internal organs/blood vessels - involuntary Cardiac - found only in the heart’s walls, involuntary Nervous Tissue receives + transmits stimuli from all parts of the body examples: brain, eye, ear, nerves, spinal cord Define biopsy tissue sample In histology, what does the sample need to be translucent - allow light to pass through it very thin (less than 20 micrometres (20μm) If sample is not translucent or very thin, diffraction (scattering) of light occurs and the image produced will be ‘blurry’. What is the purpose of “fixation” Fixation = biopsy is often preserved in a series of chemicals that protect it from damage. Fixation removes water from sample, stiffens the biopsy Define ‘In-vitro’ reflects how the cells are when grown outside the body How are cells grown + studied grown in a dish/flask Topic 2 - Embryology, Normal range and Congenital Problems 2  studied using an inverted microscope staining makes microscopic structures visible How are tissues treated when observed under a microscope Fixed (formaldehyde/frozen) - preserves tissue structure Sectioned (microtome) - used to cut thin sections of tissue Stained (haematoxyln, eosin) - providing good tissue definition under a microscope. Compare TEM and SEM Scanning electron microscopy (SEM) reveals cell surface details transmission electron microscopy (TEM) provides high-resolution images of intracellular structures and organelles. Simple Tissue vs Compound Tissue Transverse vs Longitudinal image Topic 2 - Embryology, Normal range and Congenital Problems 3  Lecture 2 - organisation of the body, serous membranes, fascia & components, planes & surface anatomy. What is the serous membrane and What 3 parts does the serous membrane have serous membranes (fluid) are formed from the mesoderm - lines body wall + covers internal organs , acts as a lubricant to reduce friction from muscle movement Visceral membrane - surrounds perimeter of an organ Parietal membrane = connects organ to body wall cavity = potential space (white blob = aorta) (black blob = notochord) Topic 2 - Embryology, Normal range and Congenital Problems 4  define peritoneum (intraperitoneal) organs are fully encased by serous membrane The pericardium is a fibrous sac that encloses the heart and great vessels define retroperitoneal organs are not fully encased by serious membrane 2 potential spaces in the lungs pleural cavity - The pleural cavity is the space that lies between the pleura, the two thin membranes that line and surround the lungs. The pleural cavity contains a small amount of liquid known as pleural fluid, which provides lubrication as the lungs expand and contract during respiration pericardial cavity - critical role in protecting and supporting the heart Topic 2 - Embryology, Normal range and Congenital Problems 5  why is a human body symmetrical externally, but internal is asymmetrical? Our external body is organized into segments called dermatomes, which come from Somites. Each dermatome is connected to a specific nerve. These left-right differences occur because certain molecules and genes are not equally active on both sides of the primitive streak during gastrulation. This uneven activity leads to the formation of our internal organs with their distinct left-right arrangements. What are potential spaces Potential spaces are small spaces initially that have the potential to expand. They are not rigid Technical definition: Areas where two surface membranes meet with a thin fluid- filled gap. Examples include serous membranes, fascia planes, and collapsible tubes/spaces. What are real spaces spaces that remain open when empty rigid, consistent in shape example: airways define fascia band/sheet of connective tissue, primarily collagen, beneath the skin that attaches, stabilises, encloses & separates muscles and organs Superficial fascia beneath skin - Loose and fatty contains collagen, fat cells & elastic tissue… Topic 2 - Embryology, Normal range and Congenital Problems 6  Deep fascia Tough, strong sheet of fibers Covers muscles and creates compartments Can facilitate infection spread Has implications in case of bleeding What germ layer forms the heart mesoderm Compare monozygotic and dizygotic Monozygotic – one fertilised egg splits into 2 babies with the same genetic information Dizygotic - 2 eggs are fertilised by 2 sperm and produce 2 genetically unique children. TUTORIAL 2a Embryology 1- 2021 (1).docx Topic 2 - Embryology, Normal range and Congenital Problems 7  2b Embryology 2 - 2021.docx 2c Normal range and Variation - 2023.docx 2d Congenital Problems - 2021.docx Topic 2 - Embryology, Normal range and Congenital Problems 8