Human Anatomy Lecture 4 PDF

 LECTURE 4 DR.NIBRAS RIYADH Cartilage is a tough but flexible tissue that is the main type of connective tissue in the body. Around 65–80% of cartilage is water, although that decreases in older people, and the rest is a gel-like substance called the ‘matrix’ that gives it its form and function...

 LECTURE 4 DR.NIBRAS RIYADH Cartilage is a tough but flexible tissue that is the main type of connective tissue in the body. Around 65–80% of cartilage is water, although that decreases in older people, and the rest is a gel-like substance called the ‘matrix’ that gives it its form and function. being responsible for its firmness and resilience The perichondrium is a dense layer of fibrous connective tissue that covers many types of cartilage in the body cartilage made of a dense extracellular matrix (ECM) with a sparse distribution of highly specialized cells called chondrocytes. The ECM is principally composed of water, collagen, and proteoglycans, with other noncollagenous proteins and glycoproteins present in lesser amounts. There are three types of cartilage: 1. Hyaline cartilage has a high proportion of amorphous matrix the most widespread type and resembles glass. plays an important part in the growth in length of long bones. Hyaline cartilage is slippery and smooth which helps your bones move smoothly past each other in your joints. It's flexible but strong enough to help your joints hold their shape. SITES : in adults, hyaline cartilage is located in the articular surfaces of movable joints, in the walls of the respiratory tracts (nose, larynx, trachea, and bronchi), in the costal cartilages, and in the epiphyseal plates of long bones. Hyaline cartilage 2. Fibrocartilage has many collagen fibers embedded in a small amount of matrix and is found in the discs within joints (e.g., the temporomandibular joint and knee joint) and on the articular surfaces of the clavicle and mandible. its main function is to act as a cushion within joints, where it helps manage compression forces and reduces stress placed on joints Locations of fibrocartilage in the human body 1-secondary cartilaginous joints:  pubic symphysis  annulus fibrosis of intervertebral discs  manubriosternal joint  glenoid labrum of shoulder joint  acetabular labrum of hip joint 2-medial and lateral menisci of the knee joint  location where tendons and ligaments attach to bone  Ulnar Triangular Fibrocartilage complex (TFCC) 3. Elasticcartilage possesses large numbers of elastic fibers embedded in matrix. As would be expected, it is flexible and is found in the auricle of the ear, the external auditory meatus, the auditory tube, and the epiglottis and tip of the nose. Hyaline cartilage and fibrocartilage tend to calcify or even ossify in later life.  the cartilage cells or chondrocytes are contained in cavities in the matrix, called cartilage lacuna  Blood Vessels Vascular System: blood circulates inside closed transport systems Types of Blood Vessels: Arteries (takes blood away from heart) Arterioles Capillary beds Venules Veins (return blood back to heart). ARTERIES  Carry blood away from the heart except for pulmonary circulation and umbilical vessels of a fetus ,Thick muscular walls,Lots of elastic tissue in wall.Relatively small lumen ,Blood under high pressure,Blood flow rapid, Blood flows in pulses  No valves  The smallest arteries,