1. 29.1 How Organ Systems Communicate QQ 4/14/08 Draw and label a nerve cell include: cell body, dendrite, axon, schwann cell, terminal, synapse.

2. 29.1 How Organ Systems Communicate KEY CONCEPT How do the organ systems communicate? By the Nervous System and Endocrine System

3. 29.1 How Organ Systems Communicate Communication systems = maintain homeostasis. A stimulus causes a response. –Responses can be chemical, cellular, or behavioral. –The nervous and endocrine systems respond to stimuli.

4. 29.1 How Organ Systems Communicate The nervous system controls thoughts, movement, and motion. This happens quickly The endocrine system controls growth, development, and digestion. This happens more slowly

5. 29.1 How Organ Systems Communicate The nervous and endocrine systems have different methods and rates of communication. The nervous system works quickly, using chemical and electrical signals. spinal chord nerves – interconnected network of cells – signals move through cells – divided into central nervous system (CNS) and peripheral nervous system (PNS)

6. 29.1 How Organ Systems Communicate The endocrine system works more slowly. –only chemical signals –signals move through bloodstream –physically unconnected organs receptor target cell not a target cell bloodstream hormone

7. 29.1 How Organ Systems Communicate KEY CONCEPT Nervous System - made of highly specialized cells.

8. 29.1 How Organ Systems Communicate Neurons are highly specialized cells. A neuron has three parts. –cell body has nucleus and organelles 1 Cell body

9. 29.1 How Organ Systems Communicate –dendrites receive impulses Neurons are highly specialized cells. A neuron has three parts. –cell body has nucleus and organelles 2 dendrites

10. 29.1 How Organ Systems Communicate –axon carries impulses 3 axon –dendrites receive impulses Neurons are highly specialized cells. A neuron has three parts. –cell body has nucleus and organelles

11. 29.1 How Organ Systems Communicate Neurons have other structures to transmit signals. –Schwann cell

12. 29.1 How Organ Systems Communicate –synapse synapse Neurons have other structures to transmit signals. –Schwann cell

13. 29.1 How Organ Systems Communicate –terminal –synapse Neurons have other structures to transmit signals. –Schwann cell axon terminal

14. 29.1 How Organ Systems Communicate Neurons receive and transmit signals. Resting potential means no signal is being transmitted. –more Na + outside of cell –more K + inside of cell

15. 29.1 How Organ Systems Communicate An action potential is a moving electrical impulse. –It is generated by a stimulus. –Na + enters, and cell becomes positively charged. –K + leaves, and area of positive charge moves. area of detail

16. 29.1 How Organ Systems Communicate A chemical signal passes between neurons. –Impulse reaches terminal. impulse

17. 29.1 How Organ Systems Communicate A chemical signal passes between neurons. –Impulse reaches terminal. impulse

18. 29.1 How Organ Systems Communicate A chemical signal passes between neurons. –Impulse reaches terminal. synapse receptor vesicles impulse neurotransmitter –Neurotransmitters released into synapse.

19. 29.1 How Organ Systems Communicate A chemical signal passes between neurons. –Impulse reaches terminal. –Neurotransmitters released into synapse. impulse synapse receptor vesicles neurotransmitter –Neurotransmitters stimulate next cell.

20. 29.1 How Organ Systems Communicate KEY CONCEPT The senses detect the internal and external environments.

21. 29.1 How Organ Systems Communicate The senses help to maintain homeostasis. Senses gather stimuli, and send it to the nervous system. Nervous system responds to stimuli. –Pupils shrink when too much light enters the eyes. –Goose bumps when cold air touches skin.

22. 29.1 How Organ Systems Communicate The senses detect physical and chemical stimuli. The eye is for vision. –Special cells collect light information (rod and cone cells) –Send information to brain in the optic nerve (a bunch of neurons)

23. 29.1 How Organ Systems Communicate The ear is for to hearing. –Special hair cells in inner ear. –Bend with sound, each hair cell is attached to a neuron that sends the information to the brain

24. 29.1 How Organ Systems Communicate Taste and smell use chemoreceptors. –Special cells in nose and mouth that are sensitive to chemicals –Attached to neurons that send the information to the brain

25. 29.1 How Organ Systems Communicate The skin senses touch. –Special cells to detect three things –Pressure / touch –Pain –Temperature pain receptor light pressure receptor hair follicle heavy pressure receptor

26. 29.1 How Organ Systems Communicate The spinal cord controls reflexes. –sensory neuron sends information to spinal cord –spinal cord directs information to motor neuron –does not involve the brain interneuron motor neurons sensory neuron

27. 29.1 How Organ Systems Communicate The PNS links the CNS to muscles and other organs. The somatic nervous system regulates voluntary movements. The autonomic nervous system controls involuntary, functions –sympathetic nervous system: “fight vs. flight” –parasympathetic nervous system: calms the body, conserves energy

28. 29.1 How Organ Systems Communicate KEY CONCEPT The endocrine system produces hormones that affect growth, development, and homeostasis.

29. 29.1 How Organ Systems Communicate Hormones influence a cell’s activities by entering the cell or binding to its membrane. Glands are organs of the endocrine system.

30. 29.1 How Organ Systems Communicate Hormones are chemical signals that influence cell’s activities. –produced by glands –travel through the circulatory system –affects cells with matching receptors target cell hormone receptor not a target cell bloodstream

31. 29.1 How Organ Systems Communicate Endocrine glands secrete hormones that act throughout the body. There are many glands located throughout the body. –Hormones travel through the bloodstream to cells with matching receptors. HYPOTHALAMUS PITUITARY THYROID THYMUS ADRENAL GLANDS PANCREAS FEMALE GONADS :OVARIES MALE GONADS : TESTES

32. 29.1 How Organ Systems Communicate The hypothalamus interacts with the nervous and endocrine systems. –a structure of both the nervous and endocrine systems –produces releasing hormones, sent to pituitary gland The pituitary gland is found below the hypothalamus in the brain. –controls growth and water levels in blood –produces releasing hormones sent throughout the body The hypothalamus is a gland found in the brain.

33. 29.1 How Organ Systems Communicate Releasing hormones stimulate other glands to produce hormones. –allow glands to communicate with one another –are used in temperature regulation