Nervous system

• Central Nervous System - Made up of brain and spinal cord Acts as body’s control center, coordinates body’s activities Impulses travel through the neurons in your body to reach the brain Central Nervous System is yellow in this diagram.
• Peripheral Nervous System - Made up of nerves that extend from the central nervous system throughout the rest of the body Carries messages between the CNS and other parts of the body The PNS has two divisions: somatic (voluntary) and autonomic (involuntary)
• Sympathetic Division- Prepares the body for action or stressful situations by increasing heart rate, dilating pupils, constricting blood vessels, etc.
• Autonomic Division- Controls involuntary actions such as heartbeat, breathing rate, digestion, blood flow, glandular secretions, etc.
• Somatic Division- Carries impulses from sensory receptors to the CNS and carries motor impulses away from the CNS to skeletal muscles Sensation- Touch, pressure, pain, temperature, etc.
• Somatic Division- Carries impulses from sensory receptors to the CNS and carries motor impulses away from the CNS to muscles and glands Sensation and voluntary movement are controlled by the Somatic division.
• Motor- Movement of voluntary muscles
• Sensory Receptor- A specialized cell that responds to stimuli and generates nerve impulses
• Parasympathetic Division- Slows down bodily functions when they are not needed; helps with digestion, urination, defecation, etc.
• Somatic Nerves- Carry impulses from sensory receptors to the CNS and carry motor commands from the CNS to muscles and glands
• Nerve Cell- Also called Neuron A nerve cell consists of three main parts: Dendrites, Soma/Cell Body, Axon
• Dendrite- Receives information from other cells and conducts it toward the cell body
• Autonomic Nerves- Control involuntary actions such as breathing, heartbeat, digestion, sweating, etc.
• Soma/Cell Body- Contains nucleus and cytoplasm; controls all activity of the neuron
• Axon- Conducts electrical signals away from the cell body towards another neuron or effector (muscle or gland)
• Soma/Cell Body- Contains nucleus and organelles necessary for metabolism and protein synthesis
• Axon- Conducts electrical signals away from the cell body
• Sympathetic Division- Prepares body for action or fight/flight response; increases heart rate, blood flow to muscles, breathing rate, etc.
• The nervous system is divided into two main parts: the central nervous system (CNS) and the peripheral nervous system (PNS)
• Neurons are specialized to receive sensory input, process that information, and send motor output to muscles and glands.
• Myelin Sheath- An insulating layer around axons made up of glial cells
• There are three types of neurons based on their structure: Sensory Neurons, Interneurons,Motor neurons
• synapse- the place where an axon of one neuron meets with the dendrite/cell body of another neuron
• Depolarization- (a change in charge due to sodium ions) creates a wave of changing charges down the axon.
• neurotransmitters- a chemical that sends signals from one neuron to another over the synapse
• Sensory Neurons- carry impulses from inside and outside the body to brain and spinal cord.
• Interneurons- found within brain and spinal cord, process incoming impulses and pass them on to motor neurons.
• Motor Neurons- carry impulses away from the brain and spinal cord
• Cerebrum- 2 hemispheres Controls memory, intelligence, muscles
• Cerebellum - Controls balance, posture and coordination
• Brainstem- Controls involuntary activities such as breathing
• Cerebrum- Controls conscious activities, intelligence, memory, language, muscles. Wrinkled with countless folds and grooves and covered with an outer layer of gray matter called the cerebral cortex. Divided into 4 lobes
• Frontal lobe- Largest Lobe Planning Complex Thinking Reasoning Imagining
• Parietal Lobe- Process messages related to: Touch Taste Temperature Controls muscle movements
• Occipital lobe- Processes Sight Receives input from the eyes Interprets color and other aspects of vision
• Temporal Lobe- Processes: Hearing Some Memory Speech
• Corpus Callosum- is the part of the brain that allows communication between the two hemispheres. It is responsible for transmitting neural messages between both the right and left hemispheres.
• Cerebellum- Muscle coordination is developed here as well as the memory of physical skills. If the cerebellum is injured, your movements become jerky. When you see an amazing athlete perform, you are watching a well-trained cerebellum at work.
• Cerebellum- Coordination and voluntary movement Balance and equilibrium Coordinates fine movements
• Brainstem- Made up of the medulla oblongata, pons and midbrain. Medulla oblongata controls involuntary activities such as heart rate and breathing Pons and midbrain act as pathways connecting various part of the brain with each other. Sometimes called the reptilian brain, because it resembles the entire brain of a reptile.