Tissues Flashcards
What are the four basic types of tissue?
Epithelial
Muscle
Nerves
Connective
Specialised connective tissue includes…
Adipose Lymphatic Blood Bone Cartilage Haemopoetic
List 6 functions of connective tissue.
Connect cells, tissues and organs Transport Protect Storage Defence Wound healing
What makes up connective tissue?
Cells, fibres and ground substance
List the three fibre types in general connective tissue.
Collagen
Reticular
Elastin
Compare reticular, collagen and elastin fibres.
Collagen is flexible with high tensile strength.
Reticular fibres provided a supportive sponges framework.
Elastin allows recoil after distension
What is a proteoglycan and where is it found?
Core protein with many glycosaminoglycans covalently bonded to it. The glycosaminoglycans attract water to aid diffusion.
Name a common glycosaminoglycan found in cartilage
Hyaluronic acid is a glycosaminoglycan attached to large proteoglycans. This is highly adapted for compression resistance and flexibility.
In ground substance of cartilage describe the common hydrophilic macromolecule.
The core protein binds glycosaminoglycans. Multiple units of this binds to one hyalurone molecule by linker proteins.
Which type of connective tissue has abundant ground substance?
Loose
Which type of connective tissue contains most collagen fibres?
Dense
Which connective tissue type transports?
Loose
Which connective tissue type contains many cell types?
Loose.
Dense only really need fibroblasts
Where do you find loose connective tissue?
Beneath epithelia
Around epithelial glands
Around small blood vessels
Why do we find loose connective tissue where we do? What’s the functional advantage of its location?
Sites for pathogen exposure and loose CT can swell
List a few places in the body loose CT is found
Epidermis
Sub mucousa of the colon
Dense connective tissue has two types what are they?
Regular
Irregular
What are the advantages of regular over irregular and vice versa?
Collagen fibres are arranged in parallel fibres in regular CT making it adapted for stress in one directions.
Irregular dense CT has collagen bundles ore tasted in many directions allowing it to resist stress in many directions.
What connects muscle to bone?
Tendon a structure of dense regular CT
Ligaments connect what to what? What type of tissue is a ligament made up of?
Bone to bone
Dense regular CT
Describe collagen fibres arrangements in ligaments.
Parallel and undulated with surrounding loose ct separating fascicles
What is apomeurosis?
Flat sheet of regular CT. layers are often arrange perpendicular to adjacent layers. Found around lumbar spine and the abdominal wall
What connective tissue is found in the dermis?
Dense irregular CT
List fixed cells in connective tissue.
Fibroblasts and myofibroblasts Melanocytes Mast cells Macrophages Adipocytes Mesenchymal stem cells
Immune wandering cells in connective tissues include…
Leucocytes Plasma cells Monocytes Eosinophils Basophils
What is the function of fibroblasts?
Synthesis and secretion of ground substance.
Myofibroblasts are specialised fibroblasts containing actin to help wound contraction
Fibroblasts are involved in the formation of collagen, what do they synthesise to help this process?
Procollagen
Why do fibroblasts have lost of rough endoplasmic reticulum?
Making lots of proteins
What are macrophages derived from?
Monocytes
List functions of macrophages:
Professional antigen presenters
Phagocytosis
Degrade debris and foreign bodies
What do mast cells look like but are not a derivative of?
Basophils
What do the granules in mast cells contain?
Histamine- increased blood vessel permeability
Heparin- anticoagulant
Substances to attract for neutrophils and Eosoniphils
Why aren’t mast cells found in the CNS?
Oedema could be damaging
What coats masts cells and what’s the role in allergy?
IgE bind allergens and the cross links establishing triggers granule release
How many kinds of collagen are the in the body?
Over 28
Which type of collagen is most abundant?
Type 1
Which type of collagen is found in reticulin?
Type 3
Where do you find type 3 collagen?
Around muscles and nerves and in the lymphatic system
Which type of collagen doesn’t make fibres?
Type 2 in hyaline and elastic
Type 4 collagen is found where in the basement membrane?
Basal lamina
Describe a collagen molecules structure
Alpha chains form a triple helix
What is the significance of vitamin C in collagen?
Intracellular Procollagen production is reliant on Vit c. Without it patients suffer scurvy and have impaired bone formation and poor wound healing.
Osteogenesis imperfect a is a result of abnormal?
Type 1 collagen
Reticulin fibres are composed of type 3 collagen. Where are they found?
Lymph nodes
Elastic fibres are made up of ?
Elastin
Elastic fibres are adundant in what structures?
Dermis, artery walls, lungs and sites bearing elastic cartilage
What is Marfans?
Automakers dominant disorder on the fibrillin gene. Elastic tissue is abnormal- blood vessels, elastic cartilage, lungs and dermis.
Tall, arachnodactyly, frequent joint dislocation, aortic rupture risk
What is found in the tunica Initima of blood vessels?
Endothelial cells
Elastin lamellae are found in which layer of blood vessel walls?
Tunica media
Collagen in blood vessels in found in which layer?
Tunica Adventia
Why is cold good for metabolism?
Brown fat metabolises in cold temperatures
Why do fat cells look empty in histology?
Chemicals used to treat and prep sample breaks adipose down
White fat cells have what features in histology?
Displaced peripheral nucleus and cytoplasm. Single fat droplet in middle
Which fat type generates heat?
Brown
Where is the nucleus in brown fat cells?
Central to many lipid droplets with lots of mitochondria - for no shivering thermogenesis.
Gherlin is released from where and does what?
Stomach and signals to the brain you are hungry
What suppresses appetite?
Leptin which is stored and secreted in fat cells when your eating.
