Lecture 9 Flashcards
How do skeletal muscles cause movement at synovial joints?
By attaching to bones via tendons and shortening to create movement.
What determines the function of a muscle?
The length, number, and arrangement of muscle fibers.
What are the three classes of levers in the body?
First-class (stabilizes joint position), second-class (overcomes heavy loads), and third-class (large range of movement and speed).
What are the three types of muscle contractions?
Concentric (muscle shortens), eccentric (muscle lengthens), and isometric (muscle length stays the same).
What are the roles of agonist, antagonist, stabilizer, and neutralizer muscles?
Agonist creates movement, antagonist opposes movement, stabilizer holds a joint still, neutralizer prevents unwanted movement.
What is the origin, insertion, and movement of the biceps brachii?
Origin: Scapula. Insertion: Radial tuberosity. Movement: Flexion at the shoulder and elbow, supination at the radioulnar joints.
What is the origin, insertion, and movement of the triceps brachii?
Origin: Scapula and humerus. Insertion: Olecranon process of ulna. Movement: Extension at the shoulder and elbow.
What is the origin, insertion, and movement of the deltoid muscle?
Origin: Scapula and clavicle. Insertion: Deltoid tuberosity. Movement: Shoulder flexion (anterior fibers), abduction (lateral fibers), and extension (posterior fibers).
What is the origin, insertion, and movement of the iliopsoas?
Origin: Iliac fossa and lumbar vertebrae. Insertion: Femur. Movement: Hip flexion.
What is the origin, insertion, and movement of the gluteus maximus?
Origin: Ilium and sacrum. Insertion: Femur. Movement: Hip extension.
What is the origin, insertion, and movement of the quadriceps femoris?
Origin: Ilium (rectus femoris) and femur (vastus muscles). Insertion: Tibial tuberosity. Movement: Hip flexion (rectus femoris) and knee extension.
What is the origin, insertion, and movement of the hamstrings?
Origin: Ischium and femur (biceps femoris). Insertion: Tibia (semimembranosus and semitendinosus) and fibula (biceps femoris). Movement: Hip extension and knee flexion/rotation.
What is the origin, insertion, and movement of the tibialis anterior?
Origin: Tibia. Insertion: Tarsals. Movement: Ankle dorsiflexion.
What is the origin, insertion, and movement of the triceps surae (gastrocnemius and soleus)?
Origin: Femur condyles (gastrocnemius) and tibia/fibula (soleus). Insertion: Calcaneus via Achilles tendon. Movement: Knee flexion (gastrocnemius) and ankle plantarflexion.
