Muscular System Quiz

How does the muscular system change between childhood and older adulthood?

• It becomes more flexible with age.

• Muscle mass and strength generally decrease.

• Muscles grow larger and stronger.

• There is no change in the muscular system.

Answer explanation

As individuals age, muscle mass and strength generally decrease due to factors like reduced physical activity and hormonal changes, making this the correct choice.

How is energy used by muscles?

• Muscles store energy indefinitely.

• Muscles use energy to contract and relax.

• Energy is not required for muscle function.

• Muscles convert energy into fat.

Answer explanation

Muscles use energy to contract and relax, which is essential for movement. This process requires ATP (adenosine triphosphate), the energy currency of cells, making the correct choice about muscle function.

What is the structure of skeletal muscles?

• They are made of smooth muscle fibers.

• They consist of long, cylindrical fibers.

• They are composed of cardiac muscle cells.

• They have a random, irregular structure.

Answer explanation

Skeletal muscles are characterized by long, cylindrical fibers that are striated and multinucleated, allowing for voluntary movement. This distinguishes them from smooth and cardiac muscles, which have different structures.

Which of the following is a major skeletal muscle found throughout the body?

• Heart muscle

• Biceps

• Intestinal muscle

• Lung muscle

Answer explanation

The biceps is a major skeletal muscle located in the upper arm, responsible for flexing the elbow. In contrast, heart muscle is cardiac, intestinal muscle is smooth, and lung muscle does not exist as a distinct muscle type.

What did Felix Gutierrez notice on his body after returning from a camping trip?

• A small black bump near his left ankle

• A rash on his arm

• A bruise on his knee

• A cut on his finger

Answer explanation

Felix Gutierrez noticed a small black bump near his left ankle after returning from his camping trip, which distinguishes it from the other options that describe different types of injuries or marks.

Who recognized the black bump as a tick?

• His father

• His sister

• His mother, Rosa

• His friend

Answer explanation

His mother, Rosa, recognized the black bump as a tick, indicating her knowledge and experience in identifying such pests, which is crucial for health and safety.

What action did Rosa take upon recognizing the tick?

• She ignored it

• She attempted to remove it

• She called a doctor immediately

• She covered it with a bandage

Answer explanation

Upon recognizing the tick, Rosa took action by attempting to remove it, which is a common and appropriate response to such a situation. Ignoring it or calling a doctor immediately would not address the immediate concern.

What percentage of a person's total body weight is made up of muscles?

• 30 percent

• 42 percent

• 50 percent

• 60 percent

Answer explanation

Muscle mass typically accounts for about 42 percent of a person's total body weight. This percentage can vary based on factors like age, sex, and fitness level, but 42 percent is a commonly accepted average.

What are the specialized cells that make up each muscle called?

• Muscle tissues

• Muscle fibers

• Muscle cells

• Muscle strands

Answer explanation

The specialized cells that make up each muscle are called muscle fibers. These fibers are long, cylindrical cells that contract to produce movement, distinguishing them from general muscle tissues or cells.

What holds muscle fibers together?

• Ligaments

• Tendons

• Connective tissue

• Cartilage

Answer explanation

Muscle fibers are held together by connective tissue, which provides support and structure. Ligaments connect bones, tendons attach muscles to bones, and cartilage provides cushioning, but it is connective tissue that binds muscle fibers.