Muscles Flashcards
True or false, skeletal muscle is always connected to at least 2 bones?
True
What is the main function of skeletal muscle?
Maintains posture
Movement
Cardiac and smooth muscle are both activated by which nervous system and are termed….?
Autonomic nervous system (parasympathetic/sympathetic)
Involuntary
Which nervous system is skeletal muscle activated by? Is it voluntary or involuntary?
Somatic.
Voluntary.
What is the function of skeletal muscle?
Voluntary movement and posture.
Purposeful locomotion.
Manipulation of external objects.
What is the function of smooth muscle?
Involuntary movement of items along lumens.
Food in GIT, urine in ureters (peristalsis).
Blood vessels, glands.
What is the function of cardiac muscle?
Pump blood, maintain blood pressure.
What are some functions of muscle in general?
Heat production - metabolic by-product.
Protein source, mobilised as energy when other CHOs fail or are used up.
What is muscle?
A group of fascicles.
True or false, muscle fibres extend the length of the muscle, from tendon to tendon.
True.
From smallest to largest, what are the components of muscle?
Myofilaments (Actin, myosin), Sarcomere, myofibril, muscle fibre, whole muscle.
What is the name for the coat which encases a muscle fibre?
Fascicle.
What is a muscle cell?
Muscle fibre. Also known as myocyte.
Does skeletal muscle have a high concentration of mitochondria?
Yes. They are high energy muscles.
What are the 4 major components of a neuro-muscular junction?
Axon, synapse, muscle fibre, myofibrils
Within a myocyte, what are the cytoplasm and smooth endoplasmic reticulum referred to?
Sarcoplasm, sarcoplasmic reticulum.
Within a myocyte, what is a mitochondria referred to? And the cell membrane?
Sarcosome is mitochondria.
Sarcolemma is membrane.
Each muscle fibre is innervated by how many neurons?
One
How many fibres can one neuron innervate?
Multiple.
What are the contractile elements within myocytes?
Myofibrils.
What gives skeletal and cardiac muscle its striated appearance?
Myofibrils.
Due to orderly arrangement of thick and thin filaments which run parallel to long axis.
Describe the structure of a Sarcomere?
Z lines are boundaries, M line is mid line of Sarcomere.
H zone is area between overlap of actin and myosin filaments, A band is length of myosin filaments, I band is area between end of myosin and the Z line.
What is the muscular protein present that holds myosin in place?
Titin
On a Sarcomere, which band/zone is the contractile area?
I band.