Human Muscles Study Guide

Muscles Study Guide

• The human body has 638 muscles.
• The largest muscle is in the thigh.
• The smallest muscle is in the ear.
• Muscles are made of protein.
• Muscles are controlled by the nervous system.
• Muscles make up more than 40-50% of body weight.

Voluntary Muscles

• Voluntary muscles are those you control.

Involuntary Muscles

• Involuntary muscles work automatically without conscious control.

Excitable/Irritable

• Muscles can respond to stimulation from nerves.
• Muscle response to stimulation can vary.

Flexible

• Muscles can return to their original shape and length after being stretched or contracted.

Abduction

• Moving parts away from the body.

Adduction

• Moving parts toward the body.

Extension

• Straightening the joint to increase the angle between parts.

Flexion

• Bending a joint to decrease the angle between parts.

Rotation

• Moving a body part around its axis.

Muscle Hypertrophy

• Muscle growth.

Muscle Atrophy

• Muscle wasting.

Antagonistic Muscles

• Muscles that work together in pairs.
• One muscle contracts while the other relaxes.

Tendons

• Connect muscles to bones.

Fascia

• Connects muscles to muscles.

Types of Muscles

• Cardiac muscle: Found in the heart; involuntary.
• Smooth muscle: Found in organs like the stomach and intestines; involuntary.
• Skeletal muscle: Attached to bones; voluntary.

Quiz Questions

• Question 1: What is the technical term for muscle growth?
  • Answer: Hypertrophy
• Question 2: What is the technical term for muscle wasting?
  • Answer: Atrophy
• Question 3: What is the term for limbs moving away from the body?
  • Answer: Abduction
• Question 4: What is the term for a movement that decreases the angle between two bones or body parts?
  • Answer: Flexion
• Question 5: What is the term for a movement that increases the angle between two bones or body parts?
  • Answer: Extension
• Question 6: Which type of muscle is found in the digestive system?
  • Answer: Smooth Muscles
• Question 7: Which type of muscle is found in the heart?
  • Answer: Cardiac Muscle
• Question 8: Which is the only type of muscle that is voluntary?
  • Answer: Skeletal Muscle
• Question 9: Which tissue connects muscle to muscle?
  • Answer: Fascia
• Question 10: Which muscles are found in the thighs?
  • Answer: Quadriceps and Hamstrings