Flashcards in Tissue Level Of Organization Deck (96):
The study of tissue
Four main tissue types
Three primary germ layers
What tissues derive from endoderm?
What tissues derive from mesoderm?
Connective (incl blood)
What tissues derive from ectoderm?
What are the five types of cell-to-cell junctions?
5. Gap junction
Transmembrane proteins fuse outer surfaces of adjacent cells
Act like surgical sutures. Prevent leaking.
Found in stomach, intestines, bladder.
Contain protein plaques which adhere to actin microfilaments, which in turn attach to transmembrane cadherin glycoproteins, which project between cells.
May form adhesion belts
Found in cells that need to be held together during contraction (ie in intestines)
Like Adherens junctions, but attach to keratin intermediate filaments. Like buttons.
Found in epidermis and cardiac cells
Half a desmosome, but connects plasma membrane to a basement membrane instead of another plasma membrane.
External membrane protein = laminin
Also the transmembrane glycoprotein is integrin rather than cadherin.
Found connecting dermis and hypodermis layers.
Tunnel-like connections (connexons) made up of glycoprotein connexin.
More of a communications bridge between cells than a structural attachment.
Allows for communicatios and transfer of waste products, chemicals or electrical signals, ions and nutrients.
Found in cornea cells, muscle and nerve cells and GI and urinary cells.
A form of embryonic connective tissue.
From which ALL connective tissue arises.
Has stem cell capabilities.
Key roles of epithelium
Protection from chemical and physical damage
Absorption of nutrients
What are the surfaces of epithelial cells?
Free side of epithelial cells that open up into the body cavity, or lumen of an organ or vessel.
May contain cilia or micro villus
The side of an epithelial cell that is shared with adjacent cells.
Where cell junctions found.
The side of an epithelial cell that is opposite to the apical surface.
Responsible for attachment to basement membranes and underlying connective tissues.
Layer that attaches epidermis to connective tissues.
What is the basement membrane composed of?
Basal lamina (collagen fibres, laminin protein, glycoproteins and proteiglycans)
Reticular lamina (fibrous proteins created by fibroblasts).
What are the three arrangement types of epithelial cells?
Single layer of cells. Easy exchange of substances
Ex. Capillaries or alveolar sacs
Appears multilayered but is on fact only single layered. Contain projections that give multilayered appearance.
Ex. Nasal mucosa
Multiple layers of cells.
Areas reuniting strength and reinforcement, or where cells slough off easily.
What are the four epithelial cell shapes?
Squamous epithelial cells
Flat. Allow for a high rate of absorption
Ex. Lungs and capillaries
Cuboidal epithelial cells
Cube shaped with micro villus. Allows for secretion and absorption.
Columnar epithelial cells
Column shaped with microvilli. Allows for secretion and absorption.
Transitional epithelial cells
Flat to cuboidal shaped.
Allows for distension and stretch.
Modified columnar cells that secrete mucous.
Unicellular exocrine glands.
Epithelial cell with cilia
Simple squamous epithelium of serous membranes
Line cavities (parietal) and the outside of organs (visceral)
Simple squamous epithelium of blood and lymphatic vessels.
Specialized epithelial/dermal tissues that produce secretions and release them into:
- the blood stream, or
- onto the surface of organs
What are the two types of glands?
Secretes into ducts to be carried away into the lumen or onto skin surfaces.
Inside space of a tubular structure.
Three functional classifications of exocrine glands:
An exocrine gland in which secretions are made in the cell and released in vesicles when ready.
Ex. Pancreatic and salivary glands
An exocrine gland in which secretions are accumulated on apical surfaces until ready for release.
Ex. Mammary glands
An exocrine gland in which secretions are accumulated in the cytosol and released in a large, excretory vesicle.
Ex. Sebaceous gland.
Programmed cell death
What are the structural classifications of exocrine glands?
Simple (does not branch)
- coiled tubular
- branched acinar
Secrete hormones into the bloodstream for use elsewhere.
Cells that make cartilage
Most numerous connective tissue cells
Make fibre and produce/secrete ground substance.
The extracellular matrix of connective tissue
Mostly composed of H2O and serves as support and binding
May be fluid, semi fluid, gelatinous or calcified.
Develop from monocytes
Involved in inflammatory and immune response
Six types of Connective tissue
Main producers of antibodies
Develops from b-lymphocytes and involved in immune response.
Produce histamines. Involved in inflammatory response
Vasodilate blood vessels; vasoconstricts bronchioles
White blood cells
Allergic and immune response
Substance that surrounds cells
Consists of ground substance an GAGs
The organic substances dissolved in ground substance. made up of proteins, polysaccharides and fibronectin.
Fluid Protein found in GAGs
Lubricates joints and helps maintain shape of eyeball.
What are the polysaccharides found in GAGs?
Chondroitin sulphate (cartilage, bone, skin and blood vessels)
Dermatan sulphate (skin, tendon, blood vessels and valves)
Keratan sulphate (bone, cartilage and eye balls)
Main adhesion protein in connective tissue.
Binds collagen fibres to ground substance, and cells to ground substance.
What are the three main types of fibres?
Made up of collagen proteins
Provide the majority of strength and stability in cartilage, tendons and ligaments
Made up of elastin and fibrillin fibres
Allows for elasticity and extensibility of fibres (up to 150% of original length).
Made up of collagen protein, but thinner and more widespread, forming a network.
Aids in support and strength.
Bed/covering formed by reticular fibres.
Forms the internal structure of organs that gives them their characteristic structure and shape.
Also forms the basement membrane
What are the two forms of embryonic connective tissue?
Embryonic tissue from which all connective tissue arises
Mucous connective tissue
Umbilical tissue with a mucous-like structure that contains a form of mesenchyme.
What are the five types of mature connective tissue?
Loose connective tissue: types
1. Loose areolar
2. Loose adipose
3. Loose reticular.
Loose areolar connective tissue
Strength, elastic and support
Found in subcutaneous layer.
Contains most types of connective tissue cells
Loose adipose connective tissue
Temperature regulation, support and protection.
Found in subcutaneous layer.
Loose reticular connective tissue
Reticular cells. Found in stroma of internal organs
Support, structure and binding together of other tissues.
What are the types of dense connective tissue?
1. Dense regular (tendons and ligaments)
2. Dense irregular (epidermis, heart valves, sheaths, periosteum)
3. Dense elastic (blood vessels, lungs) - show up as yellow.
Dense network of collagen and elastin embedded in chondroitin sulphate.
Cells of mature cartilage.
Three types of cartilage:
3. Elastic cartilage
Collagen intertwined with ground substance. Provides smooth surface for movement.
Most abundant. Weakest.
Found in long bones, ribs, trachea and nose
Collagen intertwined within the matrix.
Support, joining structures together
Strongest form of cartilage
Knees, iVDs, pubic symphysis
Mostly elastin fibres. Very stretchy.
Composed of osseus cells, red and yellow bone marrow.
Stores calcium and phosphate
Support protection structure.
2 types of bone tissue
Two types of liquid connective tissue
The extracellular matrix of blood
Three types of blood cells
Red blood cells
White bold cells
ECF of the lymphatic system. Involved in immune reactions and combatting infections.
Functions of muscle tissue
Posture and form
Three types of muscle tissue;
Skeletal (voluntary, striated)
Smooth (involuntary, unstriated)
Cardiac (involuntary, striated)
Two types of nervous tissue
Neurons (nerve cells)
Sheets of tissue that line or cover a portion of the body
Mouth to bum.
Two types of membranes:
Three types of epithelial membranes:
Protective layer that opens onto the exterior of the body.
Respiratory, GI, reproductive and urinary.
Composed of epithelial layer and connective tissue layer (Lamina propria)
Line cavities that do not open to the outside world.
Two layers: parietal (cavity wall) and visceral (surrounds organ)
In between the layers, mesothelioma secretes serous fluid, which allows for adherence and movement.
Epidermis and dermis.