Functional Anatomy and Embryology Flashcards
What are the different shapes of epithelial tissue and their examples?
Squamous: capillaries, glomeruli, alveoli
Cuboidal: organs of secretion (thyroid follicles, salivary glands, kidney tubules)
Columnar: digestive tract, uterus
What are the different layer structures of epithelial tissue and their examples?
Simple: blood vessels
Pseudostratified: trachea
Stratified: cornea
What are the different surface specialisations of epithelial tissue and their examples?
Ciliated: airways
Brush border (microvilli): gut
Keratinized: skin
What are the three mechanisms of exocrine secretion?
Merocrine: exocytosis (salivary glands)
Apocrine: part of the apical cytoplasm of the cell is lost (sweat glands, mammary glands, prostate)
Holocrine: breakdown and discharge of the entire secretory cell (sebaceous glands)
What is the structure of tight junctions?
Non-anchoring, seal inter membrane space (occludin and claudin)
What is the structure of desmosomes and hemidesmosomes?
Anchoring;
Cytoskeletal IF: keratin
Linker protein complex/anchor protein: plakoglobin, desmoplankin
Adhesion proteins: cadherin family (homophillic proteins)
What is the structure of adherence junctions?
Anchoring, concerned with cell shape;
Actin filaments
Anchor proteins: catenins, p120
Cadherin dimers (require calcium)
What is the structure of gap junctions?
1 channel = 6 connexins –> 1 connexon
Allow passage of small peptide up to 10aa, glucose, ATP, O2
What are the three types of connective tissue?
Soft, semi-hard (cartilage) and hard (bone)
What are the types of soft connective tissue?
Mesenchyme: embryonic Loose (areolar): mesentery, papillary dermis Dense: tendon, reticular dermis Reticular: bone marrow, lymph nodes Adipose: fat cells
What is ECM composed of?
Proteins: glycoproteins
- collagen, elastin, adhesive
Glycosaminoglycans (GAGs)
What are the fibrillar and sheet collagen types?
Fibrillar: Type I - skin, bone, tendons, dentine Type II - cartilage Type III - blood vessels, skin Sheet: Type IV - basement membrane
What are elastic fibres composed of?
Network of fibrillin microfibrils embedded in a core of cross-linked elastin
What are adhesive proteins?
Cross-link cells of CT with collagen, bind to integrins
Fibronectin, tenascin (produced at wounds), laminin
What are GAGs?
sugar polymers - repeating units of disaccharides, draw water due to negative ionic charge forming porous hydrated gel –> allow ECM to withstand compressive forces
What are proteoglycans?
GAGs attached to proteins through link proteins
What are the indigenous cells of CT?
Mesenchymal stem cells: fibroblasts, adipocytes, mast cells
What are the immigrant cells of CT?
Neutrophils, monocytes/macrophages, dendritic cells, eosinophils, basophils, lymphocytes
What is the epidermis composed of?
Keratinocytes (90%)
Melanocytes
Langerhan cells
Merkel cells
What does the superficial fascia contain, where is it found and what are its functions?
collagen, elastic fibers and varying amount of fat; just beneath the dermis
storage of water and fat, conduction, protection against mechanical shock, thermal insulation
What is the deep fascia composed of and what are its functions?
highly organised connective tissue layer, contains little fat
conduction, movement of muscle, attachment for some muscles, capsules around organs and glands
Where does the thoracic duct drain?
Left brachiocephalic vein between left internal jugular and subclavian
What is cartilage composed of?
chondroblasts which secrete ground substance and collagen to form a rigid gel. Chondroblasts become chondrocytes once formed.
No neurovascular elements
What is foetal skeleton formed by?
Hyaline cartilage