Lecture 4 - Muscle Tissue (Ppt) Flashcards
The ability to receive and respond to a stimulus
Excitability
The response is the generation of an electrical impulse that travels along the plasma membrane of the muscle cell
Excitability
The ability to shorten forcibly when adequately stimulated.
This is the defining property of muscle tissue.
Contractility
The ability to be stretched
Extensibility
Loosely wrapped around the actin helix and covering the myosin binding site is the filamentous protein called?
Tropomyosin
This strand is a polymer that resembles a string of beads
Actin
Bound to both the actin and the tropomyosin is a trio of proteins collectively known as?
Troponin
The portion of the sarcomere which does not contain any thick filament, contains only thin filament and is light under the microscope
I band
Hold the thick filaments to one another
M line
The sarcomere is flanked by 2 protein structures known as?
Z discs
The portion of the sarcomere which contains the think filament
A band
The A band contains..
A zone of overlap between thick and thin filaments
Contains only thick filaments
H zone
4 steps of muscle contraction
- excitation
- excitation-contraction coupling
- contraction
- relaxation
The nerve that carries signals from the spinal cord to the muscle
Axons
Within the muscle, each axon will go its own way and eventually branch into multiple small extensions called?
Telodendria
Each telodendrium ends in a bulbous swelling known as?
Synaptic end bulb
The site of interaction between a neuron and any other cell
Synapse
The synapse between neuron and a muscle
Neuromuscular junction
The minute space between the synaptic end bulb and the sarcolemma
Synaptic cleft
A depression in the sarcolemma at the synaptic cleft
Motor end plate
The synaptic end bulb is filled with vesicles that contain the neurotransmitter?
Acetylcholine
Stabilizes the sarcolemma and protects muscle fires from long-term contraction-induced damage and necrosis
Dystrophin
Examples of organ containing smooth muscles
Walls of internal organs such as:
Stomach
Intestines
Urinary bladder
Uterus
Arteries
Veins
Base of hair follicles
Iris of the eye
Functions of smooth muscle (ppt)
a. Movement of food through the digestive tract
B. Constriction of blood vessels
c. Emptying of the bladder
Characteristics of smooth muscles
Elongated cells
Cells with tapering ends
Single central nuclei
Arranged as bundles, sheets, or cords
Involuntary
Functional structures of smooth muscle fibers
Bundles
Sheets
Cords
Characteristics of cardiac muscles
-Short fibers
-Branching, weaving networks
-Overlapping sarcolemma which forms intercalated discs
Characteristics of skeletal muscle
Strongly visible striations
Elongated cells
Multinucleated cells
Parallel fibers
