The Muscular System Flashcards
What are the three types of muscle cells?
Smooth muscle, cardiac muscle and skeletal muscle
Muscle is a tissue made Up of cells that contract and relax to move parts of the body. They are specialized to convert _____________ into ____________
Chemical energy into kinetic energy
Describe the smooth muscle.
Cells are long and tapered at each end was one nuclei, found in internal organs and blood vessels, involuntary.
Where can smooth muscles be found?
In the uterus, bladder and digestive tract
Describe the cardiac muscle.
Cells have one nucleus, tubular, only found in the heart, muscle fibres connected to one another by intercollegiate discs
Describe the skeletal muscle.
Are tubular with many nuclei, contraction is under voluntary control by nervous system, found in flesh of bodies attached to the bones of the skeleton
What are the functions of skeletal muscle?
Supports the body, makes the bones move, maintain a constant body temperature, and protect internal organs and stabilize joints.
The human skeleton consists of two parts what are they called?
Axial and a appendicular
What does the axial skeletal include?
Includes bones of head, vertebral column and rib cage
What does the appendicular skeletal include?
Includes pectoral and pelvic girdle and appendages attached to them
The human skeleton is composed of three types of connective tissues what are they?
Cartilage, ligaments, and bones
Describe cartilage.
Provides flexible support and connections
Describe ligaments.
Connect bone to bone in joints
Describe bones.
Provide strong, rigid framework for the body
Inside each muscle sheath are clusters of…
Muscle fibre bundles
Each muscle fibre bundle is made up of muscle cells called…
Muscle fibers, nerves and blood vessels
Muscle fibres consist of cylindrical subunits called…
Myofibrils
Myofibrils are made up of…
Myofilaments
What part of the muscle cell is responsible for the storage of calcium ions to aid in muscle contraction?
Sarcoplasmic reticulum
Calcium binding to _________ Initiates skeletal muscle contraction.
Troponin
Protein bands that connect sarcomeres are called…
Z discs
The thick filaments of a myofibril Are composed of…
Myosin
And skeletal and cardiac muscles relaxation occurs as ________ ions are pumped backed into the sarcoplasmic reticulum.
Calcium
Which molecule contains a binding site for the attachment of myosin heads?
Actin
Osteoporosis is the…
Loss of calcium from hard bone
The site of communication between a neuron and a muscle fibre is called a…
Neuromuscular junction
What is the function of troponin and tropomyosin during skeletal muscle contraction?
To regulate bonding between actin and myosin
Each myofibril is surround by what in a muscle fiver?
Surround by sarcoplasmic reticulum
Muscle fibre is surrounded by a ______________ and form tube called _____________.
Plasma membrane; T tubules
Each myofibrils contain repeating subunits arrange end to end called…
Sarcomeres
How are sarcomeres connected to one another?
Z lines
Each sarcomeres consists of _____ and ______ filaments.
Thick; thin
Thin and thick myofilaments are made up of what two proteins?
Actin and myosin
Thin filament consists of?
Two strands of actin protein, wound around each other with Tripp in and tropomyosin at the top
Thick filaments consists of?
A bundle of myosin protein with the head protruding out
Describe a muscle contraction.
Head of myosin attaches to actin, movement of actin pulls the attached myosin head in the direction of the flex.
What is the role of calcium ions in muscle contraction?
Play an important role by creating interactions between the proteins myosin and actin
Muscle cells acquire ATP in three ways what are they?
Fermentation, aerobic respiration, and breakdown of creatine phosphate
How does creatine phosphate build up?
Creatine phosphate builds up in the resting muscle
What is a muscle twitch?
Muscle twitch is the single contraction of a muscle fibre when stimulated by an impulse above the threshold.
Describe a slow twitch.
Fibres contract slowly and resist fatigue, associated with high endurance muscles.
What are the characteristics of a slow twitch?
Tire only one fuel supply runs out, Have many mitochondria, lots of myoglobin and highly vascularized
Describe a fast twitch.
Fibres Adapted for rapid power generation, good for sprinting or weightlifting
What are the characteristics of a fast twitch?
Rich and glycogen, little myoglobin and fewer mitochondria and blood vessels
