2. The Nervous System

3. I. Function: A. Communication throughout the body. B. Coordinates functions. C. Responds to internal and external stimuli 1. Stimuli – something that causes a change in an organism II. Consists of: ▫Brain, Spinal Cord, Nerves, Sense organs

4. III. Basic structure of the Nervous System A.A nerve cell is called a neuron B.A nerve is an organ made up of many long neuron cells C.Neurons carry electrical messages called impulses throughout the body.

5. IV.Structure of a Neuron A. Cell body: contains nucleus & most of the cytoplasm B. Dendrites: projections that bring impulses into the neuron to the cell body. C. Axon: long projection that carries impulses away from cell body D Myelin sheath – protective “sheet” wrapped around the axon

7. V. Bridging the Synapse A.Neurons don’t touch one another! B.The space between two neurons is called the synapse C.In order for impulses to cross the synapse they need assistance from a neurotransmitter D.Neurotransmitter - special chemical that helps to transmit or carry impulses between neurons

8. Connection to muscles or sensory organs

9. Drugs and pain pills Drugs and pain pills work by blocking the dendrite receptors on a nerve With the receptors blocked messages, such as pain, cannot be transferred from one neuron to the next

10. VI. Types of Neurons A.Sensory neuron – carry impulses from sense organs to the spinal cord and brain B.Interneuron – process impulses in the brain and spinal cord, connect sensory and motor neurons together C.Motor neuron - carry impulses from the brain & spinal cord to muscles & glands

11. Fun Fact: Where can the largest cells in the world be found? The giraffe’s sensory and motor neurons! Some must bring impulses from the bottom of their legs to their spinal cord several meters away!!

13. Axons branching out to muscle fibers

14. REVIEW………………. What is the name of the nerve cell ? Does the stimulus travel one- way or down the neuron in two directions? Which part receives the stimuli? (The synapse, dendrites, cell body, or axon) Which is covered by a myelin sheath ? What is the purpose of the myelin sheath?

15. VII. Reflex Arc – Involuntary Responses A.A reflex is an involuntary response that is processed in the spinal cord not the brain. B.Reflexes protect the body before the brain knows what is going on

18. A. Consists of the brain and spinal cord

19. B. Parts of the Brain Spinal cord (Medulla Oblongata)

20. 1. CerebrumVoluntary or conscious activities of the body-learning, judgment 2. CerebellumCoordinates and balances the actions of the muscles 3. Medulla Oblongata (Brain Stem) Controls involuntary actions like blood pressure, heart rate, breathing, and swallowing 4. Spinal Cord The main communications link between the brain and the rest of the body

21. Parts of the Cerebrum

22. Right versus left Cerebrum

23. blow to the head does brain damage Example of amnesia & processing skills Any blow to the head does brain damage Example of amnesia & processing skills

24. A. Consists of: Sensory division and Motor division B. includes all sensory neurons, motor neurons, and sense organs

25. Of the nervous system

26. Disorders Concussion ▫Acting confused, feeling spacey, or not thinking straight ▫Being drowsy, hard to wake up, or similar changes ▫Headache ▫Loss of consciousness Paralysis ▫Loss of muscle function in part of your body ▫Can be one area, widespread, one side of the body, or all of it ▫From disease or trauma to the spinal cord

27. Meningitis Infection of the membranes covering the brain or spinal cord Can be bacterial or viral http://www.youtube.com/watch?v=eVswuWrx if8http://www.youtube.com/watch?v=eVswuWrx if8 ▫Fever and chills ▫Mental status changesMental status changes ▫Nausea and vomiting ▫Sensitivity to light (photophobia)photophobia ▫Severe headache ▫Stiff neck (meningismus) Caused from chemical irritation Drug allergies Fungi Parasites Tumors

28. Brain eating amoeba http://www.youtube.com/watch?v=Zf- Py_Ehrhwhttp://www.youtube.com/watch?v=Zf- Py_Ehrhw

29. Stroke When a blood clot travels to the brain cutting off circulation

30. Brain Tumors

31. Paralysis

32. Brainpop Neurons http://www.brainpop.com/health/bodysystems/ neurons/http://www.brainpop.com/health/bodysystems/ neurons/

33. Brainpop Nervous system http://www.brainpop.com/health/bodysystems/ nervoussystem/http://www.brainpop.com/health/bodysystems/ nervoussystem/

34. (Comparison of Nervous and Endocrine Systems) Nervous system 1. Nerves secrete chemicals called neurotransmitters. 2. Help maintain homeostasis. 3. Nerve responses are rapid and of short duration. 4. Nerve impulses are transmitted through nerve cells. Endocrine system 1. Secrete chemicals called hormones. 2. Help maintain homeostasis. 3. Endocrine responses are slow but of longer duration. 4. Hormones are carried by the bloodstream

35. Main Function: It releases hormones into the blood to signal other cells to behave in certain ways. It is a slow but widespread form of communication.

36. Endocrine glands Release hormones into the bloodstream. Hormones are chemicals released in one part of the body that travel through the bloodstream and affect the activities of cells in other parts of the body. Consists of:

37. Pituitary Gland Function: It secretes nine hormones that directly regulate many body functions and controls functions of other glands. Disorders: To much growth hormones (GH) in early childhood can result in a condition called gigantism. To little GH can result in Pituitary Dwarfism. Robert Wadlow

38. Thyroid Gland Function: plays a major role in regulation the body’s metabolism. Disorders: If the Thyroid Gland produces to much Thyroxin, it can cause a condition known as Hyperthyroidism. If to little thyroxin produces it is called Hypothyroidism.

41. Pancreas Function: The Insulin and Glycogen in the Pancreas help to keep the level of glucose in the blood stable. Disorders: When the Pancreas fails to produce or properly use Insulin, it can cause a condition known as Diabetes Mellitus.

42. Diabetes -- a disorder characterized by an insulin deficiency which results in an elevated blood sugar level (7 Diabetes Symptoms) 1. craving for sweets 2. craving for water 3. frequent urination 4. heart and circulation disorders 5. sudden changes in vision 6. sudden changes in weight (usually type I) 7. intense fatigue

43. Adrenal Gland Functions: -The adrenal glands release Adrenaline in the body that helps prepare for and deal with stress. -Also regulates kidney function.

44. Ovaries Functions: ▫ Pair of reproductive organs found in women that produce eggs. ▫ Also secrete estrogen and progesterone, which control ovulation and menstruation.

45. Testes Functions: ▫ Pair of reproductive glands that produces sperm. ▫ Also secrete Testosterone to give the body its masculine characteristics.

46. Interaction of Glands The hypothalamus is located in the brain and controls the release of hormones from the pituitary gland. It is an important link between the endocrine and nervous systems. http://www.biocfarm.unibo.it/aunsnc/images/3D%20Obje cts/Hypothalamus.gif

48. [Feedback] -- a type of organism self regulation -- operates on the principle that the level of one hormone in the blood inhibits or stimulates the production of another hormone (or substance)

49. http://www.brainpop.com/health/bodysystems/ endocrinesystem/http://www.brainpop.com/health/bodysystems/ endocrinesystem/

50. Hormones http://www.brainpop.com/health/bodysystems/ hormones/