Question

the functional classification scheme is concerned only with pns structures. it divides them into two principal subdivisions (see figure 7.2).
the sensory division, or afferent (afer-ent, literally \to go toward\) division, consists of nerves (composed of many individual nerve fibers) that convey impulses to the (1 ) nervous system from sensory receptors located in various parts of the body. the sensory division keeps the cns constantly informed of events going on both inside and outside the body. sensory fibers delivering (2 ) from the skin, skeletal muscles, and joints are called somatic (soma = body) sensory (afferent) fibers, whereas those transmitting impulses from the visceral organs are called visceral sensory (afferent) fibers.
the motor division, or efferent (efer-rent) division, carries impulses from the cns to effector organs, the muscles and glands. these impulses (3 ) muscles and glands, that is, they effect (bring about or cause) a motor response.
the motor division in turn has two subdivisions (see figure 7.2):

• the somatic (so - matik) nervous system allows us to consciously, or voluntarily, control our skeletal muscles. hence, we often refer to this subdivision as the (4 ) nervous system. however, not all skeletal muscle activity controlled by this motor division is voluntary. skeletal muscle reflexes, such as the stretch reflex (described later in the chapter), are initiated involuntarily by these same fibers.
• the autonomic (awto - nomik) nervous system (ans) regulates events that are automatic, or involuntary, such as the activity of smooth muscle, cardiac muscle, and glands. this subdivision, commonly called the (5 ) nervous system, itself has two parts, the sympathetic and parasympathetic, which typically bring about opposite effects. what one stimulates, the other inhibits. we will describe these later.

although it is simpler to study the nervous system in terms of its subdivisions, remember that these subdivisions are made for the sake of convenience only. remember that the nervous system acts as a coordinated unit, both structurally and functionally.

1. impulses 2. activate 3. voluntary 4. involuntary 5. central

1. involuntary 2. central 3. impulses 4. activate 5. voluntary

1. voluntary 2. involuntary 3. central 4. impulses 5. activate

1. central 2. impulses 3. activate 4. voluntary 5. involuntary

1. activate 2. voluntary 3. involuntary 4. central 5. impulses

Explanation:

The sensory division of the PNS conveys impulses to the central nervous system (CNS). Sensory fibers deliver impulses from different body - parts. The motor division's impulses activate muscles and glands. The somatic nervous system is often called the voluntary nervous system, and the autonomic nervous system is the involuntary nervous system.

Answer:

1. central
2. impulses
3. activate
4. voluntary
5. involuntary