Cells and Tissues: Muscle and Nervous Tissue Flashcards
Muscle tissue description
tissue that is made of contractile cells (muscle fibres) that contract to make body parts move and generates heat
What is muscle tissue comprised of?
It is made up of elongated cells (muscle cells or muscle fibres or myocytes)
What is the function of muscle tissue?
To use energy from the hydrolysis of ATP to generate contractile forces, producing body movements, maintains posture and generates heat
What are the three types of muscle tissue?
Skeletal, cardiac and smooth muscle (these comprise more than 50% of body tissue mass)
Where are skeletal muscle attached?
To bones via tendons
What is skeletal muscle comprised of?
Long, cylindrical fibres in the tissue that make it look striated. It is also multinucleated (many peripheral nuclei pushed to the side)
The function of skeletal muscle?
Motion, posture, heat production and protection
Is skeletal muscle voluntary?
It is considered voluntary because contraction and relaxation are under conscious control. However, some things like posture are not voluntary
What is the stapedius and where is it located?
The smallest skeletal muscle in the body (1.25mm) and is located in the ear
What is hyperacusis?
Excessively sensitive hearing -
What is Bell’s Palsey?
A condition where paralysis of the facial nerve causes muscular weakness in one side of the face and hyperacusis
What is the sartorius and where is it located?
The longest skeletal muscle (60cm) which is located in the anterior region of the thigh?
What is the function of the sartorius?
Flexes, abducts, and laterally rotates thigh/hip; flexes knee
What are myofibrils?
Protein structures (diameter is 2 micrometres) that run the entire length of the sarcoplasm (cytoplasm), made up of filaments
What is sarcoplasm?
The cytoplasm in skeletal muscle
What is sarcolemma?
is the plasma membrane of a striated muscle fibre cell
What are myofibrils made of?
Thin and thick filaments
What type of filament is Actin?
The thin filament in myofibrils (8 nm diam; 1-2 μm long)
What type of filament is myosin?
The thick filament in myofibrils (16 nm diam; 1-2 μm long)
What is a sarcomere?
A structural unit of a myofibril in striated muscle
What is epimysium?
dense irregular connective tissue surrounding a muscle
What is perimysium?
the sheath of connective tissue surrounding a bundle of muscle fibres
What is endomysium?
a layer of areolar connective tissue that ensheaths each individual muscle fibre/ muscle cell. Capillaries and nerves are on this layer
What is the A band?
The dark middle area of the sarcomere, containing all thick filaments
What is the I band?
Area of sarcomere containing thin filaments only
What is the H zone?
Area of sarcomere containing thick filaments only
What is the M line?
Middle of the sarcomere, holds thick filaments in place and binds to titin
What is the Z disc?
Provides anchorage for thin filaments (I band) and titin while also linking filaments of adjacent sarcomeres
What is titin?
The ‘molecular spring’ that links the M line to the Z disc