201 L1 Flashcards
Histology
Why are tissues different from each other?
They are composed of different cell types, which have different functions, therefore allowing different body functions
Name the two components that make up all tissue types.
Cells
Extracellular matrix
Name the 4 different tissue types.
Epithelia
Connective
Muscle
Nervous
What are the living and non-living components of tissue?
Cells - living
ECM - non - living
What are the two components that make up the ECM?
Fibres
Ground substance
What are the 3 fibres that contribute to the composition of the ECM?
Collagen fibres - bundled
Reticular fibres - non bundled collagen
Elastin fibres - elastic
what makes up the ground substance of the ECM?
Glycosaminoglycans (GAGs)
Proteoglycans
Glycoproteins
GAGs are ———- and make the tissue ———–
GAGs are hydrophilic (love water) and make the tissue squishy
Proteoglycans aid ———- and contribute to the ECMs ability to resist ————-
Proteoglycans aid cell migration and contribute to the ECMs ability to resist compression.
What functions do glycoproteins have in the ECM?
Help stabilize the ECM by binding to other matrix components and to integrins in the cell membrane.
What function does fibronectin have as a glycoprotein in the ECM?
Fibronectin can bind to collagen, proteoglycans and intigrins in the cell membrane to aid cell migration.
What are chondronectin and osteonectin similar to in the ECM?
Fibronectin
All can bind to collagen, proteoglycans and integrins.
Where is chondronectin found?
Carilage
Where is Osteonectin found?
Bone
Osteonectin may help the bindings of ———- ———- ——— ——– to ——— in the ECM.
Osteonectin may help the binding of calcium hydroxyapatite crystals to collagen in the ECM.
The ground substance resists force of ———- while fibres withstand —— ——.
The ground substance resists force of compression while fibres withstand tensile force.
Name the tissue described below:
Covers exposed surfaces, lines internal passageways & chambers, produces glandular secretions
Epithelia
Name the tissue described below:
Fill internal spaces, provide structural support, store energy
Connective
Name the tissue described below:
Contracts to produce active movement
Muscle
Name the tissue described below:
Conduct electrical impulses, carries information
Nervous
What quality of the connective tissue ground substance allows the exchange of nutrients and waste between cells and the blood supply?
The hydrated nature of the connective tissue ground substance.
What cells produce most of the ground substance ECM?
Fibroblasts
What effect does the ECM have on cells?
The ECM can modify cell shape and function, regulate cell development, migration, and survival.
What cells are connective tissue derived from?
Mesodermal mesenchyme cells.
Mesodermal mesenchyme cells secrete the —- —— ——- which is crucial for providing tissue with ——- ——.
Mesodermal mesenchyme cells secrete the extracellular matrix which is crucial for providing tissue with structural strength.
Is connective tissue clasified primarily on the characteristics of the fibrous or non fibrous part of the ECM?
Non- fibrous
Name the types of connective tissue
CT proper - loose or Dense
Fluid CT - Blood & lymph
Supporting CT - Bone & Cartilage
Name the 3 types of Loose CT proper
Areolar tissue
Adipose tissue
Reticular tissue
Name the 3 types of Dense CT proper
Dense regular
Dense irregular
Elastic
Name the 3 types of cartilage
Hylaine cartilage
Fibrous cartilage
Elastic cartilage
The ECM for bone & cartilage is ———
A) syrupy
B) stiff
C) liquid
B) Stiff
The ECM for CT proper is —–
A) stiff
B) syrupy
C) liquid
B) syrupy
CT proper is ———-, has a —— cell density and a —— ECM
A) vascularised or non-vascularised
B) High or Low
C) Rich or Poor
CT proper is highly vascularised, has a low cell density and a rich ECM.
What are the 3 main types of fibres for CT proper?
Collagen, reticular and elastic
What is the most common fibre in CT proper?
Collagen
Collagen fibres are made up of ——– ——- that are ——-. the fibres are highly resistant to ——- because they are unable to be ———. However collagen fibres are ———.
Collagen fibres are made up of collagen fibrils that are bundled. The fibres are highly resistant to tension because they are unable to be stretched. However collagen fibres are flexible.
Reticular fibres are made up of ——– ——- that are ——-. The fibres are ——- and arranged in a ——- providing a supportive ——— ——— for cellular elements.
Reticular fibres are made up of collagen fibrils that are not bundled. The fibres are thin and arranged in a mesh providing a supportive lattice structure for cellular elements.
Elastic fibres are ——— fibres made of ——- arranged in a —– ——— providing the tissue with —– to ——- and ———–
Elastic fibres are branched fibres made of elastin arranged in a 3D network providing the tissue with resistance to stretching and deformation.
Name the fixed cells and their functions that are in the connective tissue.
Fibroblasts - produce CT fibres
Fibrocytes - maintain CT fibres and matrix
fixed macrophages - phagocytise pathogens and damaged cells
adipocytes - store lipid reserves
Mesenchymal cells - CT stem cells which differentiate into other cell types
Melanocytes - synthesize melanin
Name the wandering cells and their functions, that have usually escaped the blood system.
Free macrophages - mobile phagocytic cells
mast cells - stimulate inflammation
Lymphocytes - immune response
Neutrophils and eosinophils - phagocytic blood cells that mobilize during infection or tissue injury.
What are the main fixed cells?
Adipocytes
What cells are more prevalent in areas where infectious pathogens are present.
fixed macrophages
Where are blood vessels located and what is their function?
Located in CT
Provide nutrients
Are blood vessels a part of the CT?
No
Loose CT Fibres are packed/not-packed well/poorly vascularised Usually supports -------- tissue, filling spaces between ------- and ------- fibres, forming layers around small ------- --------. Usually composed of equal/non-equal parts of cells, fibres and non-fibrous ECM. Most numerous cells are ------. Most numerous fibres are -------. Flexible/ not flexible Resistant/ not resistant to stress
Loose CT Fibres are not-packed well vascularised Usually supports epithelial tissue, filling spaces between nerves and muscle fibres, forming layers around small blood vessels. Usually composed of equal parts of cells, fibres and non-fibrous ECM. Most numerous cells are fibroblasts. Most numerous fibres are collagen. Flexible not very resistant to stress
Classify the CT described below:
Collagen fibres are tightly packed and are primarily oriented in the same direction.
Fibroblasts and fibrocytes are more flattened so the nuclei are elongated.
Dense regular CT
Classify the CT described below:
Collagen bundled fibres are tightly packed and organised in different directions. This helps the tissue withstand stress from different directions.
Dense irregular CT
What CT is found in tissues where the forces that are needed to be resisted come in a particular direction. Give an example of this tissue type.
Dense regular CT
Muscle
Fibronectin can bind to —— and —— to form a ——- ——. It can also bind to ——- for —— ——- and ——-.
Fibronectin can bind to collagen and GAGs to form a strong network. It can also bind to intigrins for cell adhesion and migration.