Additional causes of bleeding in early pregnancy include: 1  Cervical changes. During pregnancy, extra blood flows to the cervix. 2  Infection. Any infection of the cervix, vagina, or a sexually transmitted infection (such as chlamydia, gonorrhea, or herpes) can cause bleeding in the first trimester.
A: Afferent neurons are special nerve cells that are responsible for carrying nerve impulses from the receptors to the central nervous system. Efferent neurons carry nerve impulses from the central nervous system to the muscles and glands. Continue Reading.
A: Afferent neurons, also known as sensory neurons, carry sensory information to the central nervous system, or CNS. These neurons interact with efferent and interneurons to produce reactions based on sensations. The majority of afferent neurons in the body's peripheries are unipolar.