Test: Movement And Locomotion - Class 9 MCQ

Antagonistic muscles are pairs of muscles that cause opposite movements. For example, when one muscle contracts to flex the arm, its antagonist relaxes to allow the extension of the arm. This coordinated action is essential for smooth and controlled movements.

Cardiac muscle is the type of muscle found in the heart. It is unique in that it contracts involuntarily and rhythmically, ensuring a continuous supply of blood throughout the body. This muscle type is specialized for endurance and rapid contractions, essential for maintaining life.

Long bones are characterized by their hollow structure filled with bone marrow. This cavity can contain yellow marrow, which stores fat, and red marrow, which produces blood cells. The hollow design helps reduce weight while maintaining strength.

The human skeleton is divided into two main parts: the axial skeleton, which includes the skull, vertebral column, ribs, and sternum, and the appendicular skeleton, which comprises the bones of the limbs and girdles. This classification helps in understanding the structural organization of the skeleton.

Smooth muscle is responsible for involuntary actions in the body, such as the movements of the digestive tract and blood vessels. Unlike skeletal muscle, which is under voluntary control, smooth muscle operates automatically without conscious effort.

Calcium is primarily stored in bones. It plays a critical role in various bodily functions, including muscle contraction, nerve signaling, and blood clotting. The bones act as a reservoir, releasing calcium when needed to maintain homeostasis.

The ball and socket joint allows for the greatest range of motion among all joint types. Examples include the shoulder and hip joints, where a spherical end of one bone fits into a cup-like depression of another bone, enabling multidirectional movement. This design is crucial for activities that require extensive mobility.

The sacrum is unique because it is formed by five fused vertebrae, creating a strong triangular structure that connects the spine to the hip bones. This fusion provides stability and support to the pelvis.

Long bones are found in the limbs of the human skeleton, such as the femur in the thigh and the humerus in the upper arm. These bones are characterized by their length and play a significant role in supporting weight and facilitating movement.

Synovial fluid lubricates joints, reducing friction between the articular cartilage of synovial joints during movement. This fluid is crucial for maintaining joint health and facilitating smooth motion.

The vertebral column consists of 33 vertebrae, which are divided into five regions: cervical, thoracic, lumbar, sacral, and coccygeal. This structure provides support for the body and protects the spinal cord.

The elbow is classified as a hinge joint, allowing movement primarily in one plane, similar to a door hinge. This structure enables flexion and extension of the lower arm, making it essential for many daily activities.

The periosteum is a membrane that covers the outer surface of bones, comprised of an outer fibrous layer and an inner cellular layer rich in blood vessels. It plays a vital role in bone growth, repair, and nutrition.

Bones are the primary structure that encases and protects vital organs in the body. For example, the skull protects the brain, while the ribcage shields the heart and lungs. This protective function is essential for safeguarding our internal organs from injury.

Cartilage provides support and flexibility in various parts of the skeleton, such as the nose and ears. It is a flexible connective tissue that can absorb shock and reduce friction at joints.

Floating ribs are classified as false ribs because they do not attach directly to the sternum. They are the 11th and 12th pairs of ribs, which are only connected to the vertebrae at the back, providing some protection without a front connection.

The rib cage is formed by the ribs and the sternum, along with the thoracic vertebrae. This structure protects vital organs within the thoracic cavity, such as the heart and lungs.

Ligaments are the connective tissues that join bones to other bones at joints. They provide stability and support to the skeletal system, ensuring that bones remain aligned during movement.

The human skeleton plays a crucial role in facilitating locomotion, which is the ability to move from one place to another. This is achieved through the interaction of bones and muscles, allowing for movement at joints. Understanding this function highlights the importance of the skeletal system in physical activity and overall mobility.

Energy storage is not a function of the human skeleton. While bones store essential minerals like calcium and phosphorus and are involved in blood cell formation, they do not serve as an energy reservoir. Adipose tissue is primarily responsible for energy storage in the body.