Chapter+9+Muscular+System+NC+1500

What are the three major types of muscle tissue in the human body?

Skeletal muscle, cardiac muscle, and smooth muscle.

What is the primary function of cardiac muscle tissue?

To pump blood through the heart.

What type of muscle tissue is characterized by striations and voluntary control?

Skeletal muscle tissue.

What is the role of tendons in skeletal muscle structure?

Tendons connect muscles to bones, allowing for movement.

Define a motor unit.

A motor unit consists of a motor neuron and the muscle fibers it innervates.

What does the sliding filament model describe?

It explains how muscle contraction occurs as thick and thin myofilaments slide past each other.

What is the basic functional unit of muscle contraction?

The sarcomere.

What is the difference between isotonic and isometric contractions?

Isotonic contractions produce movement, while isometric contractions increase tension without movement.

What is hypertrophy in the context of skeletal muscle?

An increase in muscle size due to regular exercise.

What are angular movements?

Movements that change the angle between two bones at their joint, such as flexion and extension.

What does the term 'sarcomere' refer to?

The basic functional (contractile) unit of a muscle fiber.

What is the primary effect of regular exercise on skeletal muscles?

It improves muscle tone, posture, and increases muscle efficiency.

What muscle action is produced by the biceps brachii?

Flexion of the forearm.

What are Dorsiflexion and Plantar flexion?

Dorsiflexion is elevation of the foot's top (toes up), while Plantar flexion is pointing toes down.

What is muscular dystrophy?

A group of genetic disorders characterized by muscle atrophy or wasting.

What is myasthenia gravis?

A chronic autoimmune disease where the immune system attacks acetylcholine receptors, leading to muscle weakness.

What is the role of acetylcholine in muscle contraction?

Acetylcholine is a neurotransmitter that stimulates the contraction process when released by the motor unit.

What are intercalated disks?

Unique dark bands that characterize cardiac muscle tissue and help synchronize heart contractions.

What are the primary muscles involved in plantar flexion?

Gastrocnemius and soleus.

Explain the concept of fatigue in muscles.

Fatigue occurs when muscle fibers are stimulated repeatedly without sufficient rest, leading to reduced strength of contraction.

Define the term 'prime mover' in muscle action.

The muscle whose contraction is primarily responsible for producing a specific movement.

What is the function of smooth muscle tissue?

To move substances through hollow organs, such as the digestive tract.