Which of the following glands produces oil that lubricates hair follicles?

A. Erythrocytes: Erythrocytes, or red blood cells, are primarily involved in transporting oxygen from the lungs to the tissues and carbon dioxide from the tissues to the lungs. They do not play a direct role in protecting the body from pathogens.

B. Electrolytes: Electrolytes are ions in the blood and other fluids that are important for maintaining fluid balance, nerve function, and muscle function. They are not directly involved in the immune response or protection against pathogens.

C. Leukocytes: Leukocytes, or white blood cells, are key components of the immune system. They are involved in defending the body against pathogens such as bacteria, viruses, and other foreign substances through various immune responses.

D. Thrombocytes: Thrombocytes, or platelets, are primarily involved in blood clotting and preventing bleeding by aggregating at sites of injury. They do not have a direct role in protecting the body from pathogens.

A. Insertion site:
The insertion site refers to the point where a muscle attaches to a bone or structure that it moves. While it is important in understanding muscle function, it is not specifically the point of contact between a nerve ending and a muscle fiber.

B. Interneuron:
Interneurons are a type of neuron found within the central nervous system that connect other neurons. They are not involved in the direct contact between nerve endings and muscle fibers.

C. Neuromuscular junction:
The neuromuscular junction is the specialized synapse or connection point between a motor neuron and a muscle fiber. It is where the nerve ending communicates with the muscle fiber to initiate muscle contraction, making this the correct term for the point of contact.

D. Origin site:
The origin site is the point where a muscle attaches to a stationary bone or structure. It is not the site where nerve endings interact with muscle fibers. The neuromuscular junction is specifically responsible for this interaction.