Muscle and Nervous Tissue Flashcards
Muscular Tissue Characterisitics
- Cellularity (more cells than matrix)
- High Vacularity (high demand for O2, C6H12O6, H2O & wast removal.)
- Tremendous relationship with nervous system.
- Cells are lifelong & in Permanent GO (growth arrest)
- Exception is smooth m+ of uterus during pregnancy
- If m+ dies, it’s replaced with dense CT (scar tissue) which is strong but not contractile.
Types of Muscle Tissue
Skeletal m+
Cardiac m+
Smooth m+
Skeletal m+ characteristics
- Can only contract & get shorter
- Pull as a team
- Voluntary
- Long, lots of nuclei and mitochondria
- Increase in size with use
- Striated
- (A & I Bonds)
Cardiac m+ Characterisitics
- Only one nuclei
- Cells are short & branched
- Self contracting
- Use Free FattyAcids (FFA) as fuel.
- Gap junctions form intercalculated discs-contract as a unit
Smooth m+ Characteristics
- Form walls of hollow organs, medium & large blood vessels, branchiole tubes
- Involuntary > sensitive to nerve stimulation and hormones
- Very strong & can hold a contraction longer than skeletal.
- Can come out of GO in special circumstances.
- Not Striated
- Tapered Ends
Nervous Tissue Characterisitics
-
Lifelong (permanent GO) & require the greatest up keep
- Have their own “support staff” called glia cells
- High nutrient need= HIGH VASCULARITY
- Can’t survive long being cutoff from O2 or glucose
-
Glia cells are in reversable GO & can even respecialize (Change jobs-turn into a brain tumor)
- Can be a source of brain tumors
What is a cell?
A neuron
Neuron
Carry messages from one to another using electrical charges or chemicals
Dendrite
Receives the message
Perikaryon
Cell body (peri=around, keeps nucleus)
Axon
Carries message away from cell body
Bouton
Release or send the message on
Synapse
Space that the message has to travel to reach the dendrite of the next neuron
Synaptic Vessels
Carries message until it reaches the end of the bouton vessel
-Releases messages through exocytosis
What do cells contain
contractile proteins- actin & myosin.