1. Nervous, Integumentary & Endocrine Systems Ch. 35-2, 35-3, 36-3, 39-1 & 39-2

2. I. Chapter 35-2 & 35-3: Nervous System B. FUNCTION: Coordinates & controls body’s response to internal/external environment A. STRUCTURES: Brain, spinal cord, nerves, sense organs, receptors

3. II. Nervous System – has 2 major divisions: A.Central Nervous System (CNS) analyzes & interprets messages received from neurons Brain & spinal cord

4. 1. Brain FUNCTION: Oversees daily operation of body & interprets info it receives

5. 1) Cerebrum – Largest, voluntary activities, senses, intelligence, learning & judgment. Consists of approx. 10 billion neurons! a. Parts

6. 2) Cerebellum – 2nd largest. muscle coordination & balance

7. 3) Brain stem – links the cerebrum w/ spinal cord. Breathing, swallowing controlled here

8. http://www.sciencebob.com/graphics/brain.jpg

9. http://schools.lwsd.org/Juanita/staff/kohlwes/Sensory.htm

10. 2. Spinal Cord – links brain to body. Reflexes are processed here Brain Spinal cordBody

14. B. Peripheral Nervous System (PNS)- has 2 parts nerves outside the brain and spinal cord. Send and receive messages with the CNS

15. 1. Somatic Nervous System - VOLUNTARY Relays info. from senses CNS muscles Ex. Reach for a book

16. 2. Autonomic Nervous System - INVOLUNTARY Relays info from CNS internal organs ex. Heart rate, breathing

17. -REFLEX ARC – rapid, involuntary muscle movement Involves only neurons & spinal cord Brain gets bypassed!!

18. III. Structure of a NEURON (nerve cell) 1. DENDRITES – 1 st to receive impulse 3. NUCLEUS 2. CELL BODY -surrounds nucleus

19. 4. AXON – carries impulse away from cell body 5. MYELIN SHEATH – insulates/ prevents loss of impulse 6. AXON TERMINAL – end of neuron

21. IV. Types of Neurons A. SENSORY neuron – from body to CNS (sense stimuli) B. INTERNEURONS –from CNS to motor neurons (connect) C. MOTOR neuron – from CNS to muscle/gland (move)

22. V. Neuron Organization A. Neurons don’t touch! C. SYNAPSE = space between 2 neurons B. IMPULSE = electrochemical messages

25. http://shp.by.ru/spravka/ neurosci/

26. Receptors and Sense Organs Sensory receptors are neurons that are specialized to detect a stimulus. They are found in HIGH concentration in the sense organs (eyes, ears, nose, mouth & skin). They are found in LOW concentration throughout the rest of the body.

27. Types Types of Sensory Receptors 1. Mechanoreceptors: Respond to movement, pressure, tension 2. Photoreceptors: Respond to variations in light

28. 3. Chemoreceptor: Respond to chemicals 4. Thermoreceptors: Respond to changes in temperature 5. Nociceptors: Respond to tissue damage &pain

29. Nervous system and drugs 1. Stimulants a. Cocaine, nicotine, caffeine, amphetamines

30. b. Increase the speed of messages being sent - Feeling of energy and wellness c. After effect wears off  fatigue & depression

31. 2. Depressants a. Alcohol, Barbiturates, muscle relaxers, sleeping pills b. Slows down messages - Feeling of being relaxed, calm, sleepy

32. c. Can slow down the system too much  body stops breathing

33. Section 36-3: I. Integumentary System (Skin) A. Includes skin, hair & nails B. Skin is largest organ of human body

34. C. Functions of the Skin: 1. Regulate body temperature a. Blood vessels When hot, vessels dilate & release heat

35. When cold, vessels constrict & heat is conserved b. Sweat – released by glands to cool body

36. 2. Senses – sensory neurons 3. Vitamins – when exposed to UV light, makes vitamin D detects hot/cold, pressure helps absorb calcium

37. 4. Remove Wastes Sweat – releases excess water, salts & urea 5. Protection from… Physical & chemical damage Disease (1 st line of defense)

38. D. 3 Layers of Skin: 1.Epidermis – outermost layer made of dead cells & constantly replaced a. Keratin – protein that… makes nails gives tough texture “waterproof” quality

39. b. Melanin – pigment that… colors the skin protects cells from sun damage more sun exposure makes more melanin

40. 2. Dermis – inner, thicker portion of skin Contains: Nerves Blood vessels Hair follicles (warmth & protects) Sweat glands Oil glands – soften skin

41. 3. Subcutaneous Layer (Hypodermis) Mostly fat deposits Absorb impact Retain heat Store food/ energy

42. E. How Cuts Heal 1) Blood clots & cut closes 2) New cells push damaged cells to surface 3) Scab forms & WBC fight wound infection 4) New cells fill in gap of scab

44. Ch. 39-1 & 39-2: I. Endocrine System A. FUNCTION: Transmit chemical messages to control growth, development & metabolism

45. B. Hormones & Glands 1. Hormone = secreted chemical in blood stream or ducts that affects cells Ex: Human growth hormone (HGH), insulin 2. Gland = organ that releases hormones into body

46. C. Compared to nervous system 1. Message delivered throughout the body 2. Body’s response is slower than nerve impulse

47. 1) EXOCRINE gland – secrete substance through ducts (Ex: sweat, tears) D. Two Gland Types: 2) ENDOCRINE gland – secretes hormones into bloodstream

49. E. Endocrine Glands: 1. Pituitary gland (in brain) regulates other glands most important (master gland) 2. Thyroid (in neck) makes thyroxine; regulates metabolism

50. 3. Adrenal glands (above each kidney) makes epinephrine (adrenaline) ; response to stress (fight or flight) 4. Pancreas makes insulin; regulates glucose levels

51. F. Feedback Mechanism 1. adjusts to regulate amount hormone levels 2. maintains HOMEOSTASIS

52. Ex. Thyroid  thyroxine Thyroid gland controlled by hypothalamus & pituitary gland Hypothalamus sense low levels of thyroxine in blood & sends a message to pituitary releases hormone

53. Pituitary signals the thyroid to produce & release thyroxine Thyroxine sent to cells to speed metabolism

54. Low Hormone Level Increase Hormone Production High Hormone Level Decrease Hormone Production