Muscular system

• What is the focus of Unit 1 in Anatomy and Physiology?

  The effects of exercise on the muscular system
• What are the two main types of muscle mentioned?

  Smooth muscle and skeletal muscle
• What is another name for skeletal muscle?

  Striated or striped muscle
• How is skeletal muscle classified in terms of control?

  It is voluntary muscle
• What connects skeletal muscles to the skeletal system?

  Tendons
• What happens to skeletal muscles during exercise?

  They can become fatigued
• Where is cardiac muscle found?

  In the walls of the heart
• How is cardiac muscle classified in terms of control?

  It is involuntary muscle
• What is unique about cardiac muscle under a microscope?

  It is a specialized striated tissue
• What does cardiac muscle do?

  It helps to force blood through blood vessels
• How does cardiac muscle contract compared to skeletal muscle?

  It contracts quickly but does not fatigue
• What are the major skeletal muscles listed?

  • Deltoids
  • Biceps
  • Triceps
  • Wrist flexors
  • Wrist extensors
  • Supinators
  • Pronators
  • Pectorals
  • Abdominals
  • Obliques
  • Quadriceps
  • Hip flexors
  • Tibialis anterior
  • Erector spinae
  • Trapezius
  • Latissimus dorsi
  • Gluteals
  • Hamstrings
  • Gastrocnemius
  • Soleus
• What is the origin of a muscle?

  The fixed end that remains stationary
• What is the insertion of a muscle?

  The end of the muscle that moves
• What are the functions of the major muscles listed?

  • Triceps: Extends lower arm
  • Deltoids: Abducts, flexes, and extends shoulder
  • Pectorals: Horizontal adduction of shoulder
  • Biceps: Flexes arm at elbow
  • Wrist flexors: Flexes wrist
  • Wrist extensors: Extends wrist
  • Supinators: Supinate forearm (palm up)
  • Pronators: Pronate forearm (palm down)
  • Abdominals: Flex spine
  • Hip flexors: Flex hip
  • Quadriceps: Extends leg at knee
  • Hamstrings: Flexes leg at knee
  • Gastrocnemius: Plantar flexion
  • Soleus: Plantar flexion
  • Tibialis anterior: Dorsi flexion
  • Erector spinae: Extension of spine
  • Teres major: Rotation of shoulder
  • Trapezius: Pulls shoulders back
  • Latissimus dorsi: Adducts the shoulder
  • Obliques: Lateral flexion
  • Gluteus maximus: Extends hip
• What is the role of antagonist muscles?

  They relax when a contraction happens
• What is the role of agonist muscles?

  They are the contracting muscles
• What do fixator muscles do?

  They stabilize the joints involved in movement
• What are synergist muscles?

  They assist the agonist in movement
• What are examples of muscle pairs and their functions?

  • Biceps (agonist) - Latissimus Dorsi (antagonist)
  • Pectorals (agonist) - Abdominals (antagonist)
  • Hip flexor (agonist) - Hamstrings (antagonist)
  • Gastrocnemius (agonist) - Tibialis Anterior (antagonist)
• What are the movements produced by joint antagonistic pairs?

  • Elbow: Flexion (Biceps) and Extension (Triceps)
  • Knee: Flexion (Hamstrings) and Extension (Quadriceps)
  • Shoulder: Adduction (Latissimus Dorsi) and Abduction (Deltoid)
• What is a concentric muscle contraction?

  Muscle shortens as it increases tension
• What is an eccentric muscle contraction?

  Muscle lengthens as it increases tension
• What is an isometric muscle contraction?

  Muscle length does not change
• What is a characteristic of Type I muscle fibers?

  They contract slowly with less force
• What activities are Type I fibers suited for?

  Longer-duration aerobic activities
• What are Type IIa muscle fibers known for?

  Fast contracting and resistant to fatigue
• What activities are Type IIa fibers suited for?

  Middle-distance events (400/800m)
• What are Type IIx muscle fibers known for?

  Contract rapidly and produce large force
• What activities are Type IIx fibers suited for?

  Higher intensity, shorter duration exercises
• What are the characteristics of the three muscle fiber types?

  • Type I: Slow twitch, high endurance, aerobic
  • Type IIa: Fast oxidative, moderate endurance, anaerobic
  • Type IIx: Fast twitch, low endurance, anaerobic
• What are the three types of muscle fibres?

  Type I, Type IIa, Type IIx
• What is the primary characteristic of Type I muscle fibres?

  They contract slowly with less force
• Why are Type I fibres suited for aerobic activities?

  They have a high capacity for aerobic respiration
• What type of activities are Type I fibres recruited for?

  Low intensity, longer-duration activities
• What are Type IIa fibres also known as?

  Fast oxidative fibres
• What is the primary function of Type IIa fibres?

  They are suited to middle-distance events
• How do Type IIx fibres differ from Type IIa fibres?

  Type IIx fibres contract rapidly and fatigue quickly
• What type of activities are Type IIx fibres best suited for?

  Higher intensity, shorter duration exercises
• What is required for a muscle to contract?

  A nerve impulse must reach activation threshold