DP Bio B3.3 HL Muscles & motility

Which universal feature of living organisms is linked to the adaptations for movement?

• Cell division
• Movement
• Respiration
• Excretion

Answer explanation

Movement is a universal feature, allowing organisms to respond to their environment.

What is the primary role of the protein titin in muscles?

• Contracting the sarcomere
• Relaxing the muscle
• Preventing overstretching
• Producing ATP

Answer explanation

Titin helps the sarcomere to recoil after stretching and prevents overstretching.

Which of the following structures acts as an anchor for muscles in vertebrates?

• Exoskeleton
• Endoskeleton
• Ligaments
• Cartilage

Answer explanation

Endoskeletons in vertebrates serve as anchorage points for muscle attachment.

What connects motor neurons to muscle fibers?

• Synapse
• Neuromuscular junction
• Axon
• Dendrite

Answer explanation

Neuromuscular junctions are the connection points for transmitting signals from neurons to muscle fibers.

What is the role of antagonistic muscles in movement?

• They contract simultaneously.
• One muscle contracts while the other relaxes.
• They stretch the bones.
• They produce synovial fluid.

Answer explanation

Antagonistic muscles work in pairs; one contracts while the other relaxes to create movement.

What are motor units composed of?

• Motor neurons and muscle fibers
• Muscle fibers and tendons
• Motor neurons and ligaments
• Cartilage and bones

Answer explanation

Motor units consist of a motor neuron and the muscle fibers it innervates.

Which component of a synovial joint reduces friction during movement?

• Cartilage
• Ligaments
• Tendons
• Bones

Answer explanation

Cartilage covers the ends of bones in synovial joints to reduce friction.

What movement does the hip joint allow?

• Rotation only
• Flexion and extension
• Adduction and abduction
• All of the above

Answer explanation

The hip joint is a ball-and-socket joint that allows for all types of movement.

How do internal and external intercostal muscles contribute to breathing?

• By producing synovial fluid
• By moving the ribs in opposite directions
• By relaxing the diaphragm
• By contracting the lungs

Answer explanation

Internal and external intercostal muscles move the ribcage in opposite directions, aiding in breathing.

What is an example of locomotion for searching for a mate?

• Migration
• Escaping danger
• Foraging for food
• Swimming in marine mammals

Answer explanation

Migration often occurs as part of the search for a mate.