What is the name of the curved bone in the back that provides support and attachment for muscles?

Correct Answer: D

Rationale: The vertebral column, also known as the spine, is the curved bone in the back that provides support and attachment for muscles. It consists of individual vertebrae stacked on top of each other, forming a flexible and protective structure for the spinal cord. The sternum, scapula, and clavicle are bones in the chest and shoulder regions, not in the back where the vertebral column is located. Therefore, the correct answer is the vertebral column (Option D). Options A, B, and C are incorrect as they are bones situated in the chest and shoulder areas, not in the back where the vertebral column is found.

Correct Answer: A

Rationale: Sensory neurons are responsible for carrying signals from sensory receptors towards the central nervous system (brain and spinal cord), allowing the brain to receive information about the external environment. On the other hand, motor neurons carry signals away from the central nervous system to muscles and glands, enabling the brain to control voluntary and involuntary movements. Choice B is incorrect because sensory neurons do not control muscles, and motor neurons control both voluntary and involuntary muscles. Choice C is incorrect as sensory neurons are located in the peripheral nervous system, while motor neurons are located in the central nervous system. Choice D is incorrect because sensory neurons detect various stimuli such as touch, taste, smell, and sound, while motor neurons are not involved in detecting sensory stimuli.

Correct Answer: C

Rationale: The correct answer is C: Epinephrine (adrenaline). Epinephrine is produced by the adrenal medulla and is responsible for preparing the body for a stressful situation. It increases heart rate, dilates airways, and mobilizes energy stores to help the body respond to a fight-or-flight scenario. Testosterone (Choice A) is a sex hormone produced by the testes in males and in smaller amounts by the ovaries in females, not by the adrenal medulla. Cortisol (Choice B) is a stress hormone produced by the adrenal cortex, not the adrenal medulla. Growth hormone (Choice D) is produced by the pituitary gland and is involved in growth, metabolism, and various bodily functions, not by the adrenal medulla.

Correct Answer: A

Rationale: When a muscle shortens and generates force, it is contracting. Contraction is the process by which muscle fibers develop tension and exert a pulling force on the bones they are attached to, resulting in movement. Relaxation refers to the phase when a muscle returns to its original length, allowing for rest or preparation for the next contraction. Extension, on the other hand, is the movement that increases the angle between body parts, moving them further apart. Atrophy is unrelated to muscle contraction and refers to the wasting away or decrease in size of muscle tissue due to disuse or disease. Therefore, the correct answer is 'Contraction.'

Correct Answer: B

Rationale: The correct answer is B, Cardiac muscle. Cardiac muscle is the type of muscle tissue that has a unique branching network and is found in the heart. This type of muscle is involuntary and contracts rhythmically to pump blood throughout the body. Skeletal muscle, choice A, is attached to bones and is responsible for voluntary movements. Smooth muscle, choice C, is found in the walls of internal organs and blood vessels, playing a role in involuntary movements. Multifidus muscle, choice D, is a specific muscle in the back that helps with spinal stability, unrelated to the unique branching network found in cardiac muscle.