Diversity Of Cells And Their Function PDF
Document Details
Uploaded by SustainableSnake
Tags
Summary
This document details the diversity of cells and their function, providing information about various cell types and their respective roles. It covers different types of cells such as epithelial, connective, muscle, and nervous tissues, and explains their classifications, structures, and functions in the body.
Full Transcript
Diversity of Cells and Their Function 17/10/23, 7:04 PM Diversity of Cells and Their Function Haematoxylin and eosin • Haematoxylin stains acidic molecules purple • Eosin stains basic molecules pink Epithelium • Cover surfaces of the body, lines hollow organs, forms glands • Backed by a basal lam...
Diversity of Cells and Their Function 17/10/23, 7:04 PM Diversity of Cells and Their Function Haematoxylin and eosin • Haematoxylin stains acidic molecules purple • Eosin stains basic molecules pink Epithelium • Cover surfaces of the body, lines hollow organs, forms glands • Backed by a basal lamina (basement membrane) - thin layer of specialised extracellular material between the basal surface of epithelial cells and the underlying tissue • • Non-vascular Cells usually polarised - apical and basal sides differ ◦ ◦ Apical: faces the lumen of a tube or the external environment Basal: attaches to the basement membrane Functions • • • • • • Mechanical barrier Chemical barrier Absorption Secretion Containment Locomotion Classification Cell shape • • • Squamous: flattened Cuboidal: cube Columnar: tall and thin Number of layers • • • Simple: one layer Stratified: 2+ layers Pseudostratified: multiple layers, all in contact with basal lamina Cell/tissue surface specializations https://galvanized-borogovia-4fa.notion.site/Diversity-of-Cells-and-Their-Function-331bf17788fb42949ec0c02d417f7a04 Page 1 of 3 Diversity of Cells and Their Function 17/10/23, 7:04 PM • • • Microvilli Cilia Keratinized Presence of specialized cell types • e.g. goblet cells Glandular epithelia • Endocrine: product secreted towards basal end of cell and distributed by vascular system ductless • Exocrine: product secreted towards apical end of cell - ducted Connective tissue Soft connective tissue • • • Tendons, ligaments Loose: loosely packed fibres separated by ground substance Dense: densely packed bundles of collagen fibres ◦ ◦ Dense regular: fibres aligned Dense irregular: fibre bundles run in many directions Hard connective tissue • • • Strong, flexible, compressible, semi-rigid tissue 3 types of cartilage - hyaline, elastic, fibrocartilage Bone ◦ ◦ Outer shell of cortical bone makes up shaft - diaphysis Cancellous/trabecular bone occupies ends - epiphyses https://galvanized-borogovia-4fa.notion.site/Diversity-of-Cells-and-Their-Function-331bf17788fb42949ec0c02d417f7a04 Page 2 of 3 Diversity of Cells and Their Function 17/10/23, 7:04 PM Blood and lymph • Fluid connective tissues Muscle • Specialized to generate force by contraction • Force is movement of actin fibres over myosin fibres • • • Smooth muscle: involuntary, non-striated Skeletal muscle: voluntary, striated, multinucleated Cardiac: involuntary, striated, single nucleus at centre of fibre ◦ Has intercalated discs - contain many intracellular junctions for stability Nervous tissue • Consists of neurons and their supporting cells (glia) • Control function and allow for rapid communication between different parts of the body • Surrounded by connective tissue coat ◦ Meninges in CNS ◦ Epineurium in PNS Glia of the CNS • • • Astrocytes: provide support, involved in ion transport Oligodendrocytes: produce myelin Microglia: immune surveillance Glia of the PNS • Schwann cells: produce myelin and support axons https://galvanized-borogovia-4fa.notion.site/Diversity-of-Cells-and-Their-Function-331bf17788fb42949ec0c02d417f7a04 Page 3 of 3
