Session 5 Flashcards
Cells found in CT?
Immune cells - mast, plasma, macrophage,RBC,
WBC
Adipocytes - White and brown
Osteocytes - bone
Chrondrocytes - cartilage
Fibroblast - makes extracellular matrixdefine connective tissue?
Tissue of mesodermal origin with 3 basic components
Cells, extracellular matrix and ground substance.
Function of CT?
It’s role is to
support and cushion organs by filling in loose spaces between them
form tendons and ligaments hence connecting muscle to bone and bone to bone
Injury repairs - fibroblasts
Immune
Diffusion medium of waste and nutrients
What are mesenchymal cells?
Stem cells in CT, that are undifferentiated and differentiate into other cells to maintain the extracellular matrix
What does reticulum cover?
Type 3 collagen. Thin delicate network
Vessels, lymph and organs.
Smooth muscle, nerve fibres,adipocytes, some epithelial and Blood vessels,
Forms structural framework around
Liver, spleen, bone marrow and lymph nodes
What makes elastic fibres elastic and stretchy?
High lysine content
What is electric fibre made of?
Fibrillin (a microfibrillar), elastin and amorphous protein
What is ECM made of?
Glycosaminoglycans (GAGs), proteoglycans and glycoproteins
What are GAGs?
Made from Hyaluronic Acid chondrentin sulphate
Hat is proteoglycans made of?
A core protein + 100s of GAGs
What is hyaluronic acid made from?
Linear aggregation of proteoglycans and woven with collagen fibres
What colour does ECM stain with H&E?
Pink
Why is the ECM so hydrated and gel-like?
GAGs attract water
Describe Loose CT?
Eg, blood found in septa and trabeculae.
It is the framework inside organs.
Loosely packed fibres and separated by ground substance.
In oeDma, becomes distended
Describe mucous CT aka Wharton’s Jelly?
Umbilical cord and embryo CT, soft GS with lots of GAGs and delicate mesh of GAGs. Contains lots of fibroblast, few macrophages and lymphocytes.
Type 1&3
Areolar CT?
Fibroelastic, in deep skin, submucosa, peritoneum mesothelium, adventitia of BV
LOTS of Macro, fibro, mast, collagen and elastin
Dense regular?
Fewer cells and less GA
For mechanical and to trasmit forces. Parallel bundles of fibres for max tensile strength
Lig. have fibroblasts, less regularly arranged than tendons.
Tendons flattened fibroblasts, fascicles seperated by endotendineum and held together by peritendineum with fibrous sheaths
Dense irregular?
Interwoven bundles of collagen, criss cross
Found to skin dermis, capsules, large septa and trabeculae of organs,meet fascia of musclesl, peristeum and perichondrium.
Mostly collagen and small components of elastic and reticular
Diseases related to CT?
Systematic sclerosis Marfans Keloids Vitamin C dificiency (scurvy) Ethlers-Danlos disease
What makes keratin?
Keratinocytes
What does mast cells do?
In blood vessels of dermis of skin
Cytoplasmic granules containing histamine for Type 1 hypersensitivity reactions to allergic substances.
Increased vascular permeability, leakage of plasma intomextravascular sites hence local odema.
Causes urticaria and angio-odema in skin.
Neurones in skin dermis
Important for sensation
Where are melanocytes found?
Neural crest at intervals of basal layer
Granular layer contains what type of granules?
Keratohyalin granules
