2/23/15 How do nerve cells communicate?
By transmission of messages between neurons. One way direction and at the same strength.
Nervous System Nervous System: Involved in thinking, dreaming, feeling, moving and much more.
Two Main Parts Central Nervous System: brain and spinal cord. Peripheral Nervous System: nerve cells that send messages between the central nervous system & all the parts of the body
Central Nervous System Extends from the brain down the back Responsible for spinal reflexes Example: touch a hot stove, message sent to spinal cord, message sent to hand to let go.
Peripheral Nervous System Two Divisions: 1) Somatic: Transmits sensory messages to central nervous system. (activated by touch, pain, temp changes, etc) 2) Autonomic: Regulates the bodies vital functions (heartbeat, breathing, digestion, & blood pressure)
Autonomic divides into two 1) Sympathetic: Activated during action (“fight or flight”) 2) Parasympathetic: restores the body’s reserves of energy after an action has occurred. (heart rate & blood pressure normalized, breathing is slowed, digestion returns to normal)
Neurons: Tree like Structures Run through our entire body and communicate with each other Send & receive messages from other structures in the body (muscles & glands) More than 100 Billion neurons (mostly found in the brain)
Cell Body Cell Body: produces energy that fuels the activity of the cell Can have many dendrites but usually only one axon
Dendrites (Branches) Receive information from other neurons and pass the message through the cell body
Axon (Trunk) Carries messages away
D. Myelin Myelin: covers axon White fatty substance that insulates and protects the axon. Helps to speed up transmission of message.
Axon Terminals Axon Terminals: Smaller branches at the end of the axon.
Synapse Area between the axon terminal and another dendrite. New synapses can develop between neurons that were not previously connected, as when we learn something new.
Guided Practice Label the Neuron handout you have 10 min to complete. We will review Tuesday.
Brain Poster Day 1: 1.Draw a large brain/head for a human being 2.Organize it into the 4 lobes 3.Draw a neuron and label the different sections. 4.Draw how the basic nervous structure functions in the body (Central and Peripheral) (Sections 3 and 4 can be small sections off to the side.
Hand back test…….
2/24/15
Neurotransmitters: Chemicals Stored in sacs in the axon terminals When a neuron fires, it releases neurotransmitter sacs. Different chemicals cause different physical reactions Example: – Acetylcholine: involved in controlling our muscles – Dopamine: motor behavior: too much= Schizophrenia, too little = Parkinson’s disease.
The Endocrine System Endocrine System: consists of glands that secrete substances, called hormones.
Pituitary Gland: Pea sized “master gland” Growth: regulates the growth of muscles, bones, and other glands. Prolactin: stimulates milk production in women Oxytocin: stimulates labor in women
Thyroid Gland Produces thyroxin: affects the body’s metabolism
Adrenal Glands: located above the kidneys Cortical steroids: increase resistance to stress & promote muscle development Causes liver to release stored sugar, making energy available for emergencies Adrenaline & noradrenalin: helps to cope with stressful situations
Testes & Ovaries: produces testosterone, estrogen, and progesterone Testosterone: Male sex hormone, but found in females in small amounts A. After 1 st 8 weeks of development: influences the sex of a child B. Adolescence: aids in muscle & bone growth, primary & secondary sex characteristics. (Reproduction/body hair)
. Estrogen: primary and secondary sex characteristic (body hair & breast development) B. Progesterone: stimulates growth of female reproductive organs & helps prepare the body for pregnancy C. Estrogen & Progesterone: regulate menstrual cycle
Higher levels of estrogen seem to be connected with optimal cognitive functioning & feeling of well-being among women.
Day 2 Add and label the different sections of the brain we covered today – the 4 lobes and the cerebellum. (make sure each area is clearly labeled) For each of the different sections I want you to tell me exactly what each sections does. Then for each section you need to add an additional picture which gives me an idea of what each section is responsible for.