1. THE HUMAN BODY

2. Life Processes  Regulation  Nutrition  Transport  Respiration  Locomotion  Excretion

3. Organ Systems  Because humans are complex multicellular organisms, organ systems are needed to carry out the major life processes.  Levels of organization: cells  tissues  organs  systems

4. Regulation  The nervous and endocrine systems control and coordinate life activities to maintain homeostasis.  This is known as regulation.

5. Nervous System

6.  Neurons – specialized cells that transmit electrochemical messages called impulses.  This is how the body communicates rapidly producing responses of short duration.

7. Axon terminals Myelin sheath Nodes Cell body Axon Nucleus Dendrites Section 35-2 A Neuron Neuron

8. Active transport maintains nerve cells in a charged state ready to transmit a message. Nerve cells use lots of glucose and have lots of mitochondria.

9. Active Transport

10. Synapse  Neurons communicate with each other by secreting chemicals across a tiny gap called the synapse.

11. Vesicle Axon Axon terminal Synaptic cleft Neurotransmitter Receptor Dendrite of adjacent neuron Direction of Impulse Section 35-2 Figure 35-8 The Synapse Synapse

12. Used to increase alertness, relieve fatigue Used to relieve anxiety, irritability, tension Used to relieve pain Stimulants Depressants Opiates Amphetamines Barbiturates Tranquilizers Morphine Codeine Increase heart and respiratory rates; elevate blood pressure; dilate pupils; decrease appetite Slow down the actions of the central nervous system; small amounts cause calmness and relaxation; larger amounts cause slurred speech and impaired judgement Act as a depressant; cause drowsiness, restlessness, nausea Section 35-5 Commonly Abused Drugs Drug TypeMedical UseExamplesEffects on the body Drugs Affect the Synapse

13. Nervous System  Central Nervous System  Brain & spinal cord  Peripheral Nervous System  Nerve branches off the brain and spinal cord  Sense organs

14. Pons Pituitary gland Hypothalamus Cerebrum Medulla oblongata Spinal cord Cerebellum Pineal gland Thalamus Section 35-3 Figure 35-9 The Brain Brain

15. Spinal nerve Central canalGray matter White matter Meninges Section 35-3 Cross Section of the Spinal Cord Spinal Cord

16. Cerebral cortex Nasal cavity Taste bud Smell sensory area Taste sensory area Thalamus Olfactory (smell) bulb Olfactory nerve Smell receptor Taste pore Taste receptor Sensory nerve fibers Section 35-4 The Senses of Smell and Taste Sense Organs

17. Choroid Retina Blood vessels Optic nerve Fovea Vitreous humor Sclera Ligaments Iris Pupil Cornea Aqueous humor Lens Muscle Section 35-4 Figure 35-14 The Eye Eye

18. Auditory canal Tympanum Round windowEustachian tube Bone Cochlea Cochlear nerve Semicircular canals Oval window Stirrup Anvil Hammer Section 35-4 Figure 35-15 The Ear Ear