Integrating Cells Into Tissues Flashcards
How long can red blood cells be stored at 6 degrees for?
42 days
How long can red blood cells be frozen for?
10 years
How are cells held together in a tissue?
Attachment to each other- Lateral domain
What are the three main types of cell junction?
Tight junction- attach firmly
Desmosomes- further strengthen tight junctions
Gap Junctions- Communication
What do tight junctions do?
Tightly connect epithelial cells to each other by fusing the plasmalemma of adjacent epithelial cells which forms a seal and selective barrier
What do desmosomes do?
strengthen connections of adjacent cells, next to or under tight junctions, prevent stretching and twisting
What do gap junctions do?
Allow cell communications as have channels with allow molecules to pass through allowing messages to be past
What is the Basal Domain?
The Basement membrane- cells sit on this
How do cells attach to the Basement membrane?
Hemidesmosomes and Focal adhesions
Where are Hermidesomsomes found?
Found in tissues subject to abrasion like skin and epithelium of the oral cavity
What do focal adhesions do?
Anchor intracellular actin filaments to the basement membrane, role in cell movement like migration of epithelial cells in wound repair
What are Integrins?
Transmembrane proteins that attaching the cell cytoskeleton to the extracellular matrix and sense whether adhesion occurred
What is the Integrins main functions?
Attach the cell to the ECM
Signal transduction from ECM to the cell
What other functions does the Integrin have?
immune patrolling and cell migration
How can tissues be separated?
Collagenase or microdissection
What is the problem with cultured cells?
Behave differently and look different to the same cells in tissues, demonstrate contact inhibition, limited life span and demonstrate Senescence
What is Autocrine communication?
Targets the cell which secretes the signal
What is Paracrine communication?
Targets cells close to the producing cell
What is Endocrine communication?
Signal travels through the blood stream to target cells
What is synaptic communication?
Where neurotransmitters will diffuse across a synapse to target cell
What is Neurocrine communication?
Electrical signal produces a signal which travels through the blood
What is necrosis?
Cell death caused by injury, bacterial toxins or nutritional deprivation- cell burst causing damage and inflammation
What is apoptosis?
Programmed cell death
What parts of the body are static with cell renewal?
CNS, cardiac and skeletal muscle cells
What parts of the body are stable with cell renewal?
Fibroblasts, endothelium, smooth muscle cells
What parts of the body are renewing with cell renewal?
Blood, skin, gut
What are the 4 basic types of tissue?
Epithelial, Muscle, Nerve and Connective tissue
Wha are the specialised connective tissues?
Adipose, Lymphatic, Blood, Haemopoietic, Cartilage and Bone
What is an epitheloid?
Do not have surface
What are microvilli?
cytoplasmic processes that extend from the cell surface
What are stereovilli?
particularly long microvilli e.g. sensory hair cells of the ear and epididymis
What are cilia?
motile cytoplasmic processes that move forward
What is the effective stroke of cilia?
Rapid forward movement
What is the recovery stroke of cilia?
slower return stroke
