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.
- The Efferent (motor) nervous system consists of all the nerve pathways carrying signals OUT of the brain and/or spinal cord. - The Afferent (sensory) nervous system is all of the nerve pathways carrying signals TO the brain and/or spinal cord.