{
 "source": "https://peabody.kids/flashcards/bio-muscles",
 "id": "bio-muscles",
 "title": "Muscles of the Body",
 "category": "science",
 "subject": "Biology",
 "levels": [
  "6-8",
  "9-12"
 ],
 "description": "Major muscles, muscle types and how muscles work.",
 "tags": [
  "muscles",
  "anatomy"
 ],
 "frontLabel": "Muscle / term",
 "backLabel": "Meaning",
 "cards": [
  [
   "Biceps brachii",
   "Front of the upper arm; bends the elbow"
  ],
  [
   "Triceps brachii",
   "Back of the upper arm; straightens the elbow"
  ],
  [
   "Deltoid",
   "Shoulder muscle that lifts the arm"
  ],
  [
   "Pectoralis major",
   "Large chest muscle"
  ],
  [
   "Latissimus dorsi",
   "Broad muscle of the back"
  ],
  [
   "Trapezius",
   "Muscle across the upper back and neck"
  ],
  [
   "Abdominals",
   "Muscles of the belly that help the trunk bend and twist"
  ],
  [
   "Gluteus maximus",
   "The largest muscle in the body, in the buttock"
  ],
  [
   "Quadriceps",
   "Four muscles at the front of the thigh that straighten the knee"
  ],
  [
   "Hamstrings",
   "Muscles at the back of the thigh that bend the knee"
  ],
  [
   "Gastrocnemius",
   "The big calf muscle"
  ],
  [
   "Soleus",
   "Calf muscle lying below the gastrocnemius"
  ],
  [
   "Tibialis anterior",
   "Muscle on the front of the shin"
  ],
  [
   "Sartorius",
   "Long strap-like muscle of the thigh"
  ],
  [
   "Masseter",
   "Chewing muscle in the jaw"
  ],
  [
   "Orbicularis oculi",
   "Muscle that closes the eyelids"
  ],
  [
   "Diaphragm",
   "Muscle that helps you breathe"
  ],
  [
   "Intercostals",
   "Muscles between the ribs"
  ],
  [
   "Rotator cuff",
   "Group of shoulder muscles that stabilize the joint"
  ],
  [
   "Achilles tendon",
   "Strong tendon that connects the calf muscles to the heel"
  ],
  [
   "Skeletal muscle",
   "Voluntary muscle attached to bones; striped"
  ],
  [
   "Smooth muscle",
   "Involuntary muscle in organs such as the stomach"
  ],
  [
   "Cardiac muscle",
   "Muscle of the heart"
  ],
  [
   "Voluntary muscle",
   "One you can control"
  ],
  [
   "Involuntary muscle",
   "One that works without you thinking"
  ],
  [
   "Tendon",
   "Connects muscle to bone"
  ],
  [
   "Ligament",
   "Connects bone to bone"
  ],
  [
   "Contraction",
   "When a muscle shortens"
  ],
  [
   "Muscles can only",
   "Pull; they cannot push"
  ],
  [
   "Antagonistic pair",
   "Two muscles that work in opposite ways, like biceps and triceps"
  ],
  [
   "Flexor",
   "A muscle that bends a joint"
  ],
  [
   "Extensor",
   "A muscle that straightens a joint"
  ],
  [
   "Muscle fiber",
   "A long muscle cell"
  ],
  [
   "Myofibril",
   "Thread-like part inside a muscle fiber that contracts"
  ],
  [
   "Actin and myosin",
   "Proteins that slide to make muscles contract"
  ],
  [
   "ATP",
   "The energy molecule muscles use"
  ],
  [
   "Lactic acid",
   "A by-product that can build up in tired muscles"
  ],
  [
   "Muscle tone",
   "The small constant tension in resting muscles"
  ],
  [
   "Atrophy",
   "Muscle shrinking from not being used"
  ],
  [
   "Hypertrophy",
   "Muscle growing larger from use"
  ],
  [
   "Cramp",
   "A sudden painful tightening of a muscle"
  ],
  [
   "Sprain",
   "An injury that stretches or tears a ligament"
  ],
  [
   "Strain",
   "An injury that stretches or tears a muscle or tendon"
  ],
  [
   "Warm up",
   "Gentle exercise before activity to prepare muscles"
  ],
  [
   "Protein",
   "A nutrient that helps build and repair muscle"
  ],
  [
   "Fast-twitch fibers",
   "Muscle fibers that contract quickly for sprints"
  ],
  [
   "Slow-twitch fibers",
   "Muscle fibers that work for a long time without tiring"
  ],
  [
   "How many muscles do people have, about?",
   "More than 600"
  ],
  [
   "Which muscle in the body never rests?",
   "The heart"
  ],
  [
   "Neuromuscular junction",
   "Where a nerve meets a muscle to tell it to contract"
  ],
  [
   "Extraocular muscles",
   "The six muscles that move each eye"
  ],
  [
   "Sphincter",
   "A ring-shaped muscle that opens and closes an opening"
  ],
  [
   "Peristalsis",
   "Waves of smooth muscle squeezing food along"
  ],
  [
   "Sarcomere",
   "The basic contracting unit of a muscle fiber"
  ]
 ]
}