Diversity Of Cells And Their Function Flashcards
What are the 3 primary histology techniques
Tissue processing
Embedding and sectioning
Staining - colour different parts of the cell
What are the stages of tissue processing (general)
Sample removed
Fixation
Dehydration
Clearing
Infiltration
What happens during the ‘fixation’ stage of tissue processing
Sample soaked in fixated solution - acetic acid
What happens during the ‘dehydration’ stage of tissue processing
Using high concentrations of ethyl alcohol the water in the tissue is replaced with alcohol
What happens during the ‘clearing’ stage of tissue processing
Clearing agent such as xylene is used to replace the soluble alcohol
What happens during the ‘infiltration’ stage of tissue processing
Non-soluble xylene is replaced with non-soluble paraffin wax which surrounds the sample
Which tissue components take up acidic stains
Acidophilic
What colour does acid stain
Red or pink
Eosin
What tissue components take up basic stains
Basophilic
What colour does basic stain
Blue or purple
Hematoxylin
What colour does neutral stain (nt. charge)
Give different colour to different components
What does hematoxylin bind to
DNA/RNA and colours the nucleus
What does Eosin bind to
Amino acids/proteins therefore colours cytoplasm pink
What are the 4 tissue types
Epithelium
Connective tissue
Muscle tissue
Nervous tissue
What is the function of epithelial tissue
Line hollow organs
Form glands
What is the function of connective tissue
Forms framework
Fills gaps - transport of nutrients
How are the cells of muscle tissues specialised to contract
Contain more cytoskeleton
What is the function of muscle tissue
Specialised to contract
Have more cytoskeleton to contract
What are the 3 types of muscle tissue
Cardiac
Skeletal
Smooth
What does nervous tissue consist of
Neurons
supporting cells
What is the function of nervous tissue
Specialised to conduct impulses
What are the characteristics of epithelia
Polar
Tightly adherent
Avascular
What are the types of epithelium
Covering epithelium
Glandular epithelium
What is a simple epithelium
Single cell layer
What is a stratified epithelium
2 or more cell layers
What is a pseudo-stratified epithelium
Single cell layer, appears as multiple cell layers as nucleus are at different levels
What is a squamous epithelial cell
Flat
What is a transitional stratified epithelial cell
Top most cell layer varies in cell shape (squamous, cuboidal etc)
What makes a columnar epithelial cell
Height of cell is greater than the base
What are the types of epithelial cell surface specialisation
Cilia
Keratin
Microvilli
What is the function of cilia
Hair-like, move things such as mucus
Trachea
What is the function of keratin
Protection
Skin
What is the function of microvilli
Absorb nutrients
Small intestine
What are the types of glandular epithelium
Exocrine
Endocrine
Direction of secretion for exocrine glandular epithelium
Toward topmost level via duct pipe
Direction of secretion for endocrine
Toward basal lamina (down), no pipeline so dump into bloodstream (lots of capillaries)
Which type of glandular cell is avascular
Endocrine
What type of tissue is embryonic
Connective
What are the 4 types of soft connective tissue
Loose
Dense
Reticular - forms network
Adipose - fat tissue
What are the 2 types of hard connective tissue
Cartilage
Bone
What typeof tissue is blood considered
Special connective tissue, contains cells and matrix component
What are the components of connective tissue cells
Fibroblasts
Adipocytes
Osteocytes
Chondrocytes
How is the type of connective tissue determined
By types and relative amounts of components and extracellular matrix
What are the components of the connective tissue’s extracellular matrix
Fiber
Ground substance
Tissue fluid
What are the types of fibers in connective tissue ECM
Collagen
Elastic
Reticular
What makes up the ground substance in connective tissue ECM
GAGs - molecules of carbs and proteins that attract water
Glycoproteins
What is the structure of loose connective tissue
Loosely packed fibres
Abundant ground substance
Plenty of cells
What is the structure of adipose tissue
Little ECM
Little ground substance
Cells filled with fat droplets
What is the structure of dense connective tissue
Densely packed bundles of collagen fibres.
What are the characteristics of cartilage
Strong flexible
Semi-rigid due to ground substance
Avascular
What are the 3 types of cartilage
Hyaline
Elastic
Fibrous
What are the characteristics of hyaline cartilage
Clear matrix
Groups of chondrocytes
What are the characteristics of fibrocartilage
Collagen fibre bundles in ECM
Single chondrocytes in lacunae
What are the characteristics of elastic cartilage
Thin elastic fibres with ground substance in ECM
Group of chondrocytes
What does the extra-cellular matrix (ECM) consist of
collagen
ground substance
What are the components of bone
Cells
ECM
What are the properties of compact bone
dense
no cavities
What is the structure of a compact bone
Osteon arrangement with a central canal
What are the characteristics of cardiac muscle
Striated
Short with branches
Intercalated disc (junction between 2 cells)
Involuntary
Single central nucleus
What are the characteristics of skeletal muscle
Striated and cylindrical
Long and unbranched
Voluntary (move arm eg)
What are the characteristics of smooth muscle
No visible striatons
Involuntary
What are the components of nervous tissue
Supporting glial cells
Connective tissue coat
How many cytoplasmic process comes directly out of the cell body of a bipolar neuron
2
What is a pseudo-unipolar nueron
One cytoplasmic process (branch coming from cell body)
Contains a central process and peripheral process
What are the types of supporting glial cells in the central nervous system
Microgalia
Astrocytes
Oligodendrocytes (octopus)
What is the function of the Schwann cell
produce myelin
support axon
different myelination process
What are the components of spongy bone
Fine network of cavities
