Muscular System

Name one term you remember from the muscular system.

The most common lever systems in the body are those that have the applied force between the fulcrum and the resistance. These are called ______ levers.

• First Class

• Second Class

• Third Class

• Fourth Class

Place the steps that occur during a single cross bridge cycle in the correct order from left to right.

• The thin filaments are pulled toward the center of the sarcomere by the myosin heads of the thick filament. This shortens the sarcomeres in the muscle fiber and causes the whole skeletal muscle to contract.

• The activated myosin
  head binds to actin,
  forming a cross bridge.

• ADP is released and myosin
  slides the thin filament toward
  the center of the sarcomere.

• ATP is hydrolyzed to
  ADP and Pi and the
  energy released re-cocks
  the myosin head.

• ATP binds to the
  myosin head and
  detaches it from actin.

Match the following

Groups:

(a) Direct Phosphorylation

,

(b) Anaerobic Respiration

,

(c) Aerobic Respiration

• 1 ATP produced

• 38 ATP produced

• input = glucose

• provides 95% of energy for muscle activity in light to moderate exercise

• provides enough energy for 30-60 seconds of strenuous activity

• input = creatine phosphate & ADP

• kreb's cycle

• provides enough energy for 15 seconds of strenuous activity

• glycolysis

• input = glucose & other stuff

• 2 ATP produced

What is the relationship between the number of motor neurons recruited and the number of skeletal muscle fibers innervated?

• Motor neurons always innervate thousands of skeletal muscle fibers.

• A skeletal muscle fiber is innervated by multiple motor neurons.

• A motor neuron typically innervates only one skeletal muscle fiber.

• Typically, hundreds of skeletal muscle fibers are innervated by a single motor neuron.

Match the following

• involuntary & intercalated discs

• Skeletal muscle

• involuntary & non striated

• Cardiac muscle

• voluntary & striated

• Smooth Muscle

How confident do you feel in your knowledge of the muscular system? (Mark it on the scale)

Tags

NGSS.HS-LS1-4

Which learning objective are you struggling with the most?

• the components of a skeletal muscle and how they contribute to the contraction process

• all the stages that occur at the neuromuscular junction, excitation-contraction coupling, and cross bridge cycling

• motor unit & muscle twitch, and the events occurring during the 3 phases of a muscle twitch

• the 3 ways that ATP is regenerated during skeletal muscle contraction

• the components of the 3 different classes of levers