Chapter 4 Communication and Control Vocabulary Central Nervous System (CNS) Brain Spinal Cord Peripheral Nervous System ( PNS) All parts of the Nervous System Neuron A specialized cell to receive and conduct electrical impulses

Nerve A collection of fibers which impulses through travel of the body Brain Main control center Reflex An involuntary and immediate movement in response to a stimulus Retina A layer of light - sensitive cells

Cochlea A fluid-filled organ of the inner ear Endocrine System Controls body functions Gland A group of cells that make up special chemicals for your body Hormone A chemical messenger made in one cell that causes a change in another cell

Section1: The Nervous System Central Nervous System (CNS) Brain Spinal Cord The Nervous System has two parts: 1) Central (CNS) 2) Peripheral (PNS) The CNS acts as the control center for your body. The PNS carries information to and from the CNS. 1) What does the CNS consist of?___________________ Brain and Spinal cord Arms and Legs 2) What system acts as the control for your body?__________________ CNS PNS

Peripheral Nervous System All parts of the Nervous System The PNS connects all parts of your body to the CNS. The PNS uses special nerves to carry the information to the CNS. 1) ____________ uses special nerves to carry information. PNS CNS 2) __________ connects to all parts of the body. CNS PNS 3) What is the special nerve called?____________ neuron axon These special nerves are called neurons.

Nerve A collection of fibers which impulses through travel of the body Nerves are everywhere in your body. Nerves have axons that are both sensory neurons and motor neurons. The axon in the nerve transmits information from the spinal cord to the muscle fibers. 1) Nerves have _____________ that are both sensory and motor neurons. axons muscles Click on the blue button to watch a video on the nervous system.

Brain Main control center Many processes that the Brain controls happens automatically. a) You cannot stop food from digesting. b) This is called an involuntary process. c) Some actions are voluntary. d) When you move your arm, this is a voluntary process. 1) What action is an involuntary process?________________ digesting food eating food 2) What action is a voluntary action?_________________ move your arm digest food Click on the blue button to watch a video on the brain.

Section 2: Responding to the Environment Reflex An involuntary and immediate movement in response to a stimulus When you step on something sharp, pain receptors in your foot send impulses to your spinal cord. This involuntary action is called a Reflex. 1) Reflex is an ______________________action. voluntary involuntary Click on the blue buttons to watch a short video on reflexes.

Retina A layer of light - sensitive cells Your eyes are sensory organs. Your eyes detect light which enables your brain to form visual images. The retina is packed with photoreceptors. a) rods b) cones Rods are sensitive to dim light. Cones are sensitive to bright light. 1) The retina has two photoreceptors__________________________. rods & cones square & circle

Cochlea A fluid-filled organ of the inner ear Hearing A coiled tube that is found in the inner ear. Ears are specialized organs for hearing. Neurons in the cochlea change the waves into electrical impulses. Click on the blue button to watch a video on inner ear hearing. 1) What special kind of tube is found in the inner ear?__________________ square coiled 2) A fluid-filled organ in the inner ear is called?___________________ Cochlea Retina

Endocrine System Controls body functions The Endocrine System controls body functions by using chemicals that are made by the endocrine glands. a. These glands secrete hormones and regulate growth, development and homeostasis. b. regulates fluid balance. Click here to watch a video on the endocrine system. 1) What system regulates growth and development?____________________ endocrinenervous 2) The Endocrine system controls body functions by using _________________? chemicals nervous

Gland A group of cells that make up special chemicals for your body Some Endocrine Glands are: pituitary: stimulates skeletal growth regulates the amount of water in your blood thyroid: controls growth hormones for normal body growth controls your metabolism Click the blue button to watch a video on glands. 1) What gland controls growth hormones?_______________ thyroid pituitary 2) What gland stimulates skeletal growth?_____________________ thyroid pituitary

Hormone A chemical messenger made in one cell that causes a change in another cell A substance that is made on one cell or tissue and that causes a change in another cell or tissue in a different part of the body. Hormone medications can be used to treat endocrine disorders. 1) What medications can be used to treat disorders?__________________ hormone tissue 2) Hormones are __________________messengers. chemical cell Click on the blue button to watch a video on target cell interactions. Click on the blue button to watch a video on cells and tissues.