Nervous System
The Nervous System Two main systems: –Central Nervous System (CNS) The body’s decision maker –Peripheral Nervous System (PNS) 1)Gathers information 2)Transmits CNS decisions to other body parts
The Nervous System
Central Nervous System Reflexes: Three Types of Neurons Sensory neuron - a neuron that carries information from the senses to the central nervous system. Motor neuron - a neuron that carries messages from the central nervous system to the muscles of the body.
Interneuron - a neuron found in the center of the spinal cord that receives information from the sensory neurons and sends commands to the muscles through the motor neurons. – Interneurons also make up the bulk of the neurons in the brain. Central Nervous System Reflexes: Three Types of Neurons
CNS: Simple Reflex
ALS – Lou Gehrig’s Disease Amyotrophic Lateral Sclerosis -Death of motor neurons -Ice Bucket ChallengeIce Bucket Challenge
Peripheral Nervous System Peripheral nervous system (PNS) - all nerves and neurons that are not contained in the brain and spinal cord but that run through the body itself; divided into the: – Somatic nervous system – Autonomic nervous system
Somatic Nervous System Soma = body. Somatic nervous system - division of the PNS consisting of nerves that carry information from the senses to the CNS and from the CNS to the voluntary muscles of the body. – Bell rings, you get up & leave
Autonomic Nervous System Autonomic nervous system (ANS) – Division of the PNS consisting of nerves that control all of the involuntary muscles, organs, and glands. Sympathetic division (fight-or-flight system) – responsible for reacting to stressful events and bodily arousal. Parasympathetic division – restores the body to normal functioning after arousal and is responsible for the day-to-day functioning of the organs and glands.
The Endocrine Glands Endocrine glands – secrete chemicals called hormones directly into the bloodstream. Hormones – chemicals released into the bloodstream by endocrine glands. Bloodstream carries them to their target organs. Hormone chemicals then fit into receptor sites on target organs and excite them to function.
(regulates growth and controls other endocrine glands) - Most influential
(regulates growth and controls other endocrine glands) - Most influential
(regulates growth and controls other endocrine glands) - Most influential
(regulates growth and controls other endocrine glands) - Most influential
(regulates growth and controls other endocrine glands) - Most influential
(regulates growth and controls other endocrine glands) 30 different hormones to deal with stress, regulate salt intake, and provide a secondary source of sex hormones. Triggers “fight-or- flight” response. - Most influential
(regulates growth and controls other endocrine glands) 30 different hormones to deal with stress, regulate salt intake, and provide a secondary source of sex hormones. Triggers “fight-or- flight” response. - Most influential
Immune System Endocrine system linked to immune system. Immune system – system of cells, organs, and chemicals in the body that responds to attacks on the body from disease and injuries.
Immune System Thymus gland – located near the top of the sternum that produces hormones to help fight off infections and diseases.