How to Use This Presentation

1. How to Use This Presentation How to Use This Presentation • To View the presentation as a slideshow with effects select “View” on the menu bar and click on “Slide Show”, or simply press F5 on the top row of your keyboard. • To advance to the next slide click the left mouse button once. • From the Chapter screen you can click on any section to go directly to that section’s presentation. • Blank or “missing” areas of a slide will remain hidden until the left mouse button is clicked. • You may exit the slide show at any time by pressing the Esc key.

2. Resources Bellringers Chapter Presentation Transparencies Standardized Test Prep Image and Math Focus Bank CNN Videos Visual Concepts

3. Chapter 25 Communication and Control Table of Contents Section 1 The Nervous System Section 2 Responding to the Environment Section 3 The Endocrine System

4. Section1 The Nervous System Chapter 25 Bellringer • List as many functions of the brain as you can. How do you think the brain coordinates all the different activities? • Record your answers in your science journal.

5. Chapter 25 Section1 The Nervous System Objectives • Describe the relationship between the central nervous system and the peripheral nervous system. • Compare the somatic nervous system with the autonomic nervous system. • Listone function of each part of the brain.

6. Chapter 25 Section1 The Nervous System Two Systems Within a System • The central nervous system (CNS) is your brain and spinal cord. The CNS processes and responds to all messages coming from the peripheral nervous system. • The peripheral nervous system (PNS) is all of the parts of the nervous system except for the brain and the spinal cord. The PNS connects all parts of the body to the CNS.

7. Chapter 25 Section1 The Nervous System The Peripheral Nervous System • A neuron is a nerve cell that is specialized to transfer messages in the form of fast-moving electrical energy. The three parts of a neuron are the cell body, the dendrites, and the axon. • Sensory neurons gather information about what is happening in and around your body. • Neurons that send impulses from the brain and spinal cord to other systems are called motor neurons.

8. Chapter 25 Section1 The Nervous System

9. Chapter 25 Section1 The Nervous System Nerves • The central nervous system is connected to the rest of your body by nerves. • A nerve is a collection of axons bundled together with blood vessels and connective tissue. • Most nerves have axons of both sensory neurons and motor neurons.

10. Chapter 25 Section1 The Nervous System

11. Chapter 25 Section1 The Nervous System Somatic and Autonomic Nervous Systems • Somatic Nervous System Most of the neurons that are part of the somatic nervous system are under your conscious control. • Autonomic Nervous System Autonomic nerves do not need your conscious control. The autonomic nervous system controls body functions that you don’t think about, such as digestion and heart rate.

12. Chapter 25 Section1 The Nervous System The Central Nervous System • The brain is the largest organ of the nervous system. • The brain is the main control center of the nervous system. Its controls both voluntary and involuntary processes. • The brain is comprised of the cerebrum, the cerebellum, and the medulla.

13. Chapter 25 Section1 The Nervous System The Central Nervous System, continued • Thecerebrum is where you think and where most memories are stored. It controls voluntary movements and the senses.

14. Chapter 25 Section1 The Nervous System The Central Nervous System, continued • Thecerebellumprocesses sensory information from your body, such as from skeletal muscles and joints. • Themedullacontrols involuntary processes such as blood pressure, body temperature, heart rate, and involuntary breathing.

15. Chapter 25 Section1 The Nervous System

16. Chapter 25 Section1 The Nervous System The Spinal Cord • Route to the BrainThe spinal cord is made of neurons and bundles of axons that pass impulses to and from the brain. The spinal cord is surrounded by protective bones called vertebrae. • Spinal Cord Injury A spinal cord injury may block all information to and from the brain. Each year, thousands of people are paralyzed by spinal cord injuries.

17. Chapter 25 Section1 The Nervous System

18. Section2 Responding to the Environment Chapter 25 Bellringer • List the five senses, and draw the organ associated with each sense as well as an object detected by each sense. • Record your answers in your science journal.

19. Section2 Responding to the Environment Chapter 25 Objectives • List four sensations that are detected by receptors in the skin. • Describe how a feedback mechanism works. • Describe how light relates to sight. • Describe how the senses of hearing, taste, and smell work.

20. Section2 Responding to the Environment Chapter 25 Sense of Touch • Stimuli and ReceptorsTouch is what you feel when sensory receptors in the skin are stimulated. Each kind of receptor responds mainly to one kind of stimulus.

21. Section2 Responding to the Environment Chapter 25 Responding to Sensory Messages • Pain receptors in your skin activate immediate, involuntary actions called reflexes. Reflexes help you move quickly out of the way of danger. • Feedback Mechanisms are cycles of events in which information from one step controls or affects a previous step.

22. Section2 Responding to the Environment Chapter 25 Sense of Sight • Reacting to LightYour pupil is an opening that lets light enter the eye. The pupil is surrounded by the iris, a ring of muscle that controls the amount of light that enters the eye. • Focusing the Light Light travels in straight lines until it passes through the cornea and the lens. Muscles in the eye change the shape of the lens in order to focus light onto the retina.

23. Section2 Responding to the Environment Chapter 25 Human Eyes Click below to watch the Visual Concept. You may stop the video at any time by pressing the Esc key. Visual Concept

24. Section2 Responding to the Environment Chapter 25 Sense of Hearing • Each ear has an outer, middle, and inner portion.Sound waves reaching the outer ear are funneled into the middle ear and then into the inner ear before being interpreted by the brain.

25. Section2 Responding to the Environment Chapter 25 Sense of Taste • Your tongue is covered with tiny bumps called papillae. Most papillae contain taste buds. • Taste buds contain cluster of taste cells, or receptors for taste. Taste buds respond to sweetness, sourness, saltiness, and bitterness.

26. Section2 Responding to the Environment Chapter 25 Sense of Smell • Receptors for smell are located on olfactory cells in the upper part of your nasal cavity. An olfactory cell is a nerve cell that responds to chemical molecules in the air.

27. Chapter 25 Section3 The Endocrine System Bellringer • Unscramble the following words: • nalgd • meornoh • noclotr • Record your answers in your science journal.

28. Chapter 25 Section3 The Endocrine System Objectives • Explainwhy the endocrine system is important to the body. • Identify five glands of the endocrine system, and describe what their hormones do. • Describe how feedback mechanisms stop and start hormone release. • Name two hormone imbalances.

29. Chapter 25 Section3 The Endocrine System Hormones as Chemical Messengers • The endocrine system is a collection of glands and groups of cells that secrete hormones. • A gland is a group of cells that make special chemical messengers, called hormones, for your body. • A hormone is a chemical messenger made in one cell or tissue that causes a change in another cell or tissue in another part of the body.

30. Chapter 25 Section3 The Endocrine System More Endocrine Glands • Your thyroid gland controls the secretion of growth hormones for normal body growth. • Your thymus gland produces killer T cells that help destroy or neutralize cells or substances that invade your body. • Metabolism is the sum of all the chemical processes that take place in an organism.

31. Chapter 25 Section3 The Endocrine System More Endocrine Glands, continued

32. Chapter 25 Section3 The Endocrine System Controlling the Endocrine Glands • Endocrine glands control feedback mechanisms in the body. Hormone Imbalances • Occasionally, an endocrine gland makes too much or not enough of a hormone. For example, sometimes a child’s pituitary gland doesn’t make enough growth hormone. As a result, the child’s growth is stunted.

33. Chapter 25 Section3 The Endocrine System Hormone Imbalances, continued

34. Chapter 25 Communication and Control Concept Map Use the terms below to complete the concept map on the next slide.

35. Chapter 25 Concept Map

36. Chapter 25 Concept Map

37. End of Chapter 25 Show

38. Chapter 25 Communication and Control CNN Videos • Science, Technology, and Society: Correcting Colorblindness • Science, Technology, and Society: Brain Cell Visuals • Science, Technology, and Society: Learning from Frog Ears • Science, Technology, and Society: Easy Touch Toys

39. Standardized Test Preparation Chapter 25 Reading Read each of the passages. Then, answer the questions that follow each passage.

40. Standardized Test Preparation Chapter 25 Passage 1The axon terminals of neurons usually do not touch the other cells. There is a small gap between an axon terminal and another cell. This space where a neuron meets another cell is called a synapse. When a nerve impulse arrives at an axon terminal, the impulse cannot cross the gap. Instead, the impulse triggers the release of chemicals called neurotransmitters. Continued on the next slide

41. Standardized Test Preparation Chapter 25 Passage 1, continuedThese neurotransmitters cross the synapse between the axon terminal and the cell. When neurotransmitters reach the next cell, they signal the cell to react in a certain way. There are many kinds of neurotransmitters. Some neurotransmitters tell cells to start an action. Other neurotransmitters tell cells to stop an action.

42. Standardized Test Preparation Chapter 25 1.What is the space between a neuron terminal and a receiving cell called? A a neurotransmitter B a synapse C an axon D a nerve

43. Standardized Test Preparation Chapter 25 1.What is the space between a neuron terminal and a receiving cell called? A a neurotransmitter B a synapse C an axon D a nerve

44. Standardized Test Preparation Chapter 25 2. Why are neurotransmitters necessary? F They tell muscle cells to contract or relax. G They create a gap that axons must cross. H They carry messages across the synapse. I They release chemical signals called impulses.

45. Standardized Test Preparation Chapter 25 2. Why are neurotransmitters necessary? F They tell muscle cells to contract or relax. G They create a gap that axons must cross. H They carry messages across the synapse. I They release chemical signals called impulses.

46. Standardized Test Preparation Chapter 25 3.Which of the following statements is a fact in the passage? A A synapse is an extension of a nerve cell. B The space between an axon terminal and another cell is filled with neurons. C Nerve impulses jump from an axon to another cell. D There are many kinds of neurotransmitters.

47. Standardized Test Preparation Chapter 25 3.Which of the following statements is a fact in the passage? A A synapse is an extension of a nerve cell. B The space between an axon terminal and another cell is filled with neurons. C Nerve impulses jump from an axon to another cell. D There are many kinds of neurotransmitters.

48. Standardized Test Preparation Chapter 25 Passage 2Hormones are chemical messengers released by cells that regulate other cells in the body. Hormones regulate many body processes. Hormones control growth, direct the production and use of energy, keep body temperature within normal limits, and direct responses to stimuli outside the body. Hormones carry chemical messages that tell cells to change their activities. Continued on the next slide

49. Standardized Test Preparation Chapter 25 Passage 2, continuedFor example, one hormone tells the heart to beat faster. Another hormone tells certain cells to make proteins and stimulates bone and muscle growth. Each hormone communicates with specific cells. Each hormone is like a key that opens only one kind of lock. A hormone’s message can be received only by cells that have the right kind of lock. Hormones control many important body functions, so their messages must be delivered properly.

50. Standardized Test Preparation Chapter 25 1.According to the passage, which of the following statements about hormones is true? A Hormones tell cells to change their activities. B Hormones are electrical messengers. C Hormones are like locks. D Hormones are not important to your body.