Tissues PDF

🧻 Tissues Specialised cells to perform a similar function are group together to form ‘tissues’. Understanding tissues, organs and organ systems helps to understand how the systems of body work together to maintain ‘homeostasis’....

🧻 Tissues Specialised cells to perform a similar function are group together to form ‘tissues’. Understanding tissues, organs and organ systems helps to understand how the systems of body work together to maintain ‘homeostasis’. Epithelial and connective tissues are the most diverse tissue types and classified according to structure. Muscular and nervous tissues are classified according to structure and are further classified according to their function. Structure of Ephithelial tissue = One of the simplest tissue type. Cells are held together by tight junctions. Cells sit on basement membrane Usually lacks of blood supply — nutrients and O2 diffuse from underlying tissue. Often grow and divide rapidly. Tissues 1  Functions: Protection Secretion Absorption Connective Tissue Matrix (liquid, solid or gel) Fibres (Collagen & elastin) Cells Cells in connective tissue: Fibroblasts > secretes extracellular fibres, mostly made of non-stretchy collagen and very elastic elastin (both are proteins.) Mast cells > secretes histamine in inflammatory reactions and heparin, which prevents blood clotting. Macrophages > engulfs or phagocytose pathogens, ageing cells, damaged cells and cancer cells. Nervous Tissue Tissues 2  Nerve cells specialised to react stimuli to conduct impulses to various organs in the body that brings out response. = Supporting cells — Physical support, electrical insulation and metabolic exchange. Muscle Tissue Specialised tissue with the ability to contract and to conduct electrical impulses. Tissues 3