1.1.7 Major muscles in the human body

• The Latissimus Dorsi is located in the mid-back
• Arrange the following muscle groups from top to bottom based on their anatomical location:

  1️⃣ Shoulders (Deltoids)

  2️⃣ Upper arms (Biceps, Triceps)

  3️⃣ Mid-back (Latissimus Dorsi)

  4️⃣ Upper legs (Quadriceps, Hamstrings)
• The Deltoids are located at the top of the shoulders.
• The Triceps Brachii extends the elbow.
• What are the basic contractile units of skeletal muscle?

  Sarcomeres
• Myofibrils are cylindrical structures within muscle fibers that contain sarcomeres
• Match the skeletal muscle components with their descriptions:

  Muscle Fibers ↔️ Elongated cells that contract

  Myofibrils ↔️ Contain sarcomeres

  Sarcomeres ↔️ Basic contractile units

  Connective Tissues ↔️ Provide support and transmit force
• Muscle fibers are elongated cells that contract to produce movement
• What are the primary functions of the latissimus dorsi?

  Extends, adducts, and rotates arm
• The biceps brachii extends the elbow.

  False
• The hamstrings extend the knee.

  False
• Sarcomeres are responsible for muscle shortening during contraction


  True
• What structures within muscle fibers contain sarcomeres?

  Myofibrils
• What happens to sarcomeres during muscle contraction?

  They shorten
• During muscle fatigue, waste products like lactic acid accumulate, leading to muscle weakness
• Match the muscle group with an example sport:

  Chest (Pectoralis Major) ↔️ Volleyball

  Back (Latissimus Dorsi) ↔️ Swimming

  Abdomen (Rectus Abdominis) ↔️ Gymnastics

  Arms (Biceps, Triceps) ↔️ Baseball

  Legs (Quadriceps, Hamstrings) ↔️ Soccer
• The Rectus Abdominis flexes the spine and stabilizes posture.


  True
• What is the primary function of the Quadriceps muscle group?

  Extends the knee
• Which muscle group medially rotates the arm?

  Latissimus Dorsi
• What is the primary function of the Rectus Abdominis?

  Flexes the spine
• Which muscle group flexes the knee?

  Hamstrings
• Match the skeletal muscle component with its function:

  Muscle Fibers ↔️ Contract to produce movement

  Myofibrils ↔️ Contain sarcomeres and facilitate contraction

  Connective Tissues ↔️ Support, transmit force, and protect
• Sarcomeres are responsible for muscle shortening during contraction.


  True
• Sarcomeres consist of actin and myosin filaments.

  True
• Muscle fibers are arranged in parallel bundles to produce movement
• Which muscle group extends the knee?

  Quadriceps
• What are muscle fibers composed of?

  Parallel bundles of cells
• What is the role of connective tissues in muscles?

  Support, transmit force, protect
• Connective tissues wrap around muscle fibers, myofibrils, and the entire muscle


  True
• The triceps is the antagonist muscle to the biceps


  True
• Which muscle group flexes and rotates the shoulder?

  Chest
• Why is understanding major muscle groups essential?

  For effective exercise planning
• Match the arm muscles with their primary functions:

  Biceps Brachii ↔️ Flexes the elbow

  Triceps Brachii ↔️ Extends the elbow
• The Pectoralis Major is located in the front of the torso.
• The Pectoralis Major flexes and rotates the shoulder.


  True
• The Pectoralis Major extends the arm.

  False
• Arrange the following functions of major muscle groups with their corresponding locations:

  1️⃣ Flexes and rotates the shoulder (Chest)

  2️⃣ Extends, adducts, and medially rotates the arm (Back)

  3️⃣ Flexes the spine and stabilizes posture (Abdomen)

  4️⃣ Flexes the elbow (Arms)

  5️⃣ Extends the knee (Legs)

  6️⃣ Abducts, flexes, and extends the shoulder (Shoulders)
• What are muscle fibers composed of?

  Parallel bundles of cells
• What is the primary function of connective tissues in muscles?

  Support and force transmission
• What do connective tissues wrap around in muscles?

  Fibers, myofibrils, and muscles