The General Reflex

Reflex Arc Components

The pathway followed by the stimulus impulse from beginning to end is the reflex arc. The general reflex arc Figure 12-10 of the human nervous system has a minimum of five components Figure 12-10. The general reflex arc. Figure 12-10. The general reflex arc. a. The stimulus is received by a receptor organ specific to that stimulus. b. From the receptor organ, the stimulus is carried to the CNS by way of an afferent sensory neuron within the appropriate peripheral nerve. The cell body of this...

The Human Brain

Brain Lobes Bottom View

The human brain Figures 12-3 and 12-4 has three major subdivisions brainstem, cerebellum, and cerebrum. a. The Brainstem. The brainstem is the core of the brain. We consider it in three parts--the hindbrainstem, the midbrainstem, and the forebrainstem. In general, the brainstem is made up of many nuclei and fiber tracts. It is a primary coordinating center of the human nervous system. b. The Cerebellum. Over the hindbrainstem is the cerebellum. The cerebellum is connected to both the...

Secondary Sex Organs

The secondary sex organs of the female serve to transport and care for the ovum and to develop the new individual embryo and fetus . a. Uterine Tube Oviduct, Fallopian Tube . The uterine tube picks up the free ovum when it is expelled from the follicle of the ovary. The ovum stays in the uterine tube to await fertilization. If it is fertilized, it goes through the initial stages of embryonic development, and the embryo then passes on to the uterus. On the other hand, if it is not fertilized,...