Topic 6 Myology Flashcards
Specialized cells that use ATP in the generation of force?
Muscle tissue
3 types of muscle tissue ;
Functions include: body movement, substance movement, control of substance movement, thermogenesis
Skeletal, smooth cardiac
Common characteristics of muscle tissue
Electrical excitability
Contractility
Extensibility
Elasticity
The ability to respond to certain stimuli by producing electrical signals;
Electrical signals produced are called ?
Electrical excitability
(Directive from nervous system)
Action potentials (APs)
The ability of muscle tissue to generate tension (force) when stimulated by an Action Potential
Contractibility
The ability of muscle to stretch (lengthen) without being damaged;
Muscle still can contract when stretched
Extensibility
The ability of muscle tissue to return to its original shape after contraction or stretch
Elasticity
Aka striated muscle
Skeletal muscle
Striations as alternating light and dark bands that are characteristics of this muscle type;
Voluntary/ conscious control (also subject to involuntary control)
Skeletal muscle
It’s size is measured in centimetres;
Subdivided into bundles of fascicles
Muscle
It’s size measured in milimeters;
Each of these is made up of many muscle fibres
Fascicles
It’s size is measured in ‘um x100’;
Cylindrical in shape
Muscle fibres
Aka muscle cell
Term The cell (plasma) membrane of the muscle cell
Sarcolemma
Sarco=flesh
Lemma=sheath
Term
Tiny invaginations tunnels in from the sarcolemma towards the centre of the muscle fibres
Transverse tubules (T-tubules)
Term
The cytoplasm of the muscle fibres - lots of glycogen (fluid within cell)
Sarcoplasm
Term
A protein that binds o yen that has diffused into muscle fibre and delivers it to the mitochondria (power house producing cell)
Myoglobin
Muscle fibres has lots of these
Mitochondria
This type of fibre is multinucleated;
Filled with myofibrils
Muscle fibres
Aka muscle cell
Hierarchy of skeletal organization
Muscle > Fascicles (bundle of muscle fibres) > muscle fibre (muscle cell) > myofibril (organelles within the muscle cell) > sarcormere > actin & myosin (protein filaments)
These are specialized contractile organelles of muscle cell;
Measured in ‘um’ diameter
Extend the length of muscle fibre
Are held in place by cytoskeletal proteins
Contain a number of sarcomameres arranged in series (end to end)
Myofibril
Fluid filled tubes and sacs surrounding each myofibril
They store and release calcium into the cell (when it’s neede)
Sarcoplasmic reticulum
Represents the functional unit of a myofibril (of contraction)
Contain 2 contractile proteins : actin & myosin
Thick and thin filaments overlap and their interaction is what generates force/ contraction
Their overlap also creates a light and dark which gives skeletal mule its striated appearance
Sarcomere
Makes up the the thin filaments within A sarcomere
Actin
Makes up the the thick filaments within the sarcomere
Myosin
