Lesson Summary. Nervous tissue is composed of three main parts: nerves, the spinal cord and the brain. The primary function of nervous tissue is to receive stimuli and send the impulse to the spinal cord and brain. The brain sends back a response to the muscles via the nerves.ervous tissue is composed of three main parts: nerves, the spinal cord and the brain. The primary function of nervous tissue is to receive stimuli and send the impulse to the spinal cord and brain.
What Does a Low MPV Mean? MPV is the abbreviated form of Mean Platelet Volume. It is a reading which represents the size of the platelets in a blood sample and is determined by a machine. CBC or Complete Blood Profile is the test in which the calculation of this reading is usually included.
Quick Answer. Low MPV in a blood test means a person's mean platelet volume is lower than normal, according to WebMD. Mean platelet volume refers to the average size of the platelets in the blood. Continue Reading.