Skeletal and muscular systems

Which of the following statements about muscles is incorrect?

• There are more than two types of muscle tissue in the human body.

• Muscles are involved in nearly all physical activities.

• Muscles are composed of specialized, contractile cells.

• When a muscle contracts, it lengthens.

Which of the following is NOT a function of the muscular system?

• Generating heat

• Maintaining posture and body position

• Movement of substances within the body

• Transporting oxygen through the bloodstream

Which structure is an example of a voluntary muscle?

• Stomach

• Leg

• Heart

• Intestines

What type of muscle tissue pumps blood throughout the body?

• Smooth

• Cardiac

• Skeletal

• Flexible

Which type of muscle is found in internal organs, such as the stomach and intestines?

• Skeletal

• Cardiac

• Smooth

• Flexible

What type of joint allows rotational movement, such as turning your head?

• Ball-and-socket joint

• Pivot joint

• Hinge joint

• Gliding joint

What is the name of the longest bone in the human body?

• Femur

• Tibia

• Humerus

• Radius

Which condition weakens bones due to a reduction in bone density?

• Arthritis

• Osteoporosis

• Scoliosis

• Kyphosis

What neurotransmitter stimulates muscle contraction at the neuromuscular junction?

• Dopamine

• Acetylcholine

• Serotonin

• Epinephrine

Which ion is essential for initiating muscle contraction?

• Sodium

• Potassium

• Calcium

• Magnesium