15 - ...are chemical substance released from axon terminals of presynaptic : A) neurotransmitter b) receptors c) chemical vesicles d) sodium channels 16- the normal hematocrit in women is: d-41% -45% b-47% 0-42% 17 - Macula and cristae is functioning in (A) Hearing (8) Vision (C) Vestibular system (D) Smile 18 - The increasing stiffness of the lens that occurs with aging makes accommodation for near visio increasingly difficult is (A) Myopic eye (B) Hypermetropic eye (C) Presbyopia (D) Accommodation 19 - Which of the following muscle is involuntary? (A) Skeletal muscle (B) Smooth muscle (C) Cardiac muscle (D) Smooth muscle and Cardiac muscle 20 - A) cranial nerve conveys nutritive material to brain and spinal cord : b) spinal nerve c) cerebrospinal fluid d) intracellular fluid