The Human The Human BodyBody

HomeostasisHomeostasis

• Stability that results when the organism Stability that results when the organism detects changes in the environment and detects changes in the environment and responds with an appropriate corrective responds with an appropriate corrective action that returns the organism’s action that returns the organism’s systems to normal.systems to normal.

• If an organism’s monitoring systems or If an organism’s monitoring systems or control mechanisms fail, disease or death control mechanisms fail, disease or death can result.can result.

• Another phrase for this is “dynamic Another phrase for this is “dynamic equilibrium.”equilibrium.”

Feedback MechanismFeedback Mechanism

• These involve a cycle, where one These involve a cycle, where one thing happens, leading to thing happens, leading to something else, and so on.something else, and so on.

• The output of the system “feeds The output of the system “feeds back” to either change or reinforce back” to either change or reinforce the action taken by the system.the action taken by the system.

• It’s like a thermostat or central air.It’s like a thermostat or central air.

Feedback SystemsFeedback Systems

• Positive FeedbackPositive Feedback– A change prompts a A change prompts a

response, which response, which leads to a greater leads to a greater change and a change and a greater response.greater response.

– For example, For example, childbirth: each childbirth: each contraction leads to contraction leads to a stronger and a stronger and stronger one until stronger one until the baby is born.the baby is born.

• Negative FeedbackNegative Feedback– A change in the A change in the

environment can environment can prompt System 1 to prompt System 1 to send a message (often send a message (often a hormone) to System a hormone) to System 2, which responds by 2, which responds by attempting to restore attempting to restore balance.balance.

– For example, For example, regulating body regulating body temperature.temperature.

Comprehension QuestionComprehension Question

• During hot weather and vigorous During hot weather and vigorous exercise, people sweat. As the exercise, people sweat. As the water on their skin evaporates, the water on their skin evaporates, the water molecules absorb heat water molecules absorb heat energy.energy.

Explain why this process is Explain why this process is important to the individual.important to the individual.

OrganizationOrganization• CellsCells are the smallest, but they come in are the smallest, but they come in

high numbers.high numbers.• Next comes Next comes tissuestissues, which are groups of , which are groups of

cells that have a similar function. For cells that have a similar function. For example, a group of muscle cells is muscle example, a group of muscle cells is muscle tissue.tissue.

• Then come Then come organsorgans, which are different , which are different kinds of tissues that are combined to form kinds of tissues that are combined to form something that performs one of the life something that performs one of the life processes.processes.

• An An organ systemorgan system is next, which consists of is next, which consists of several organs that work together.several organs that work together.

• Finally, the Finally, the organismorganism is the largest, but you is the largest, but you only have one organism.only have one organism.

Comprehension QuestionComprehension Question

• Which sequence is listed in order Which sequence is listed in order from simplest to most complex?from simplest to most complex?

A.A. Tissue Tissue Cell Cell Organ System Organ System OrganOrgan

B.B. Cell Cell Tissue Tissue Organ Organ Organ Organ SystemSystem

C.C. Cell Cell Tissue Tissue Organism Organism Organ Organ

D.D. Organism Organism Tissue Tissue Organ Organ Organ Organ SystemSystem

The Circulatory The Circulatory SystemSystem

CirculationCirculation

• Circulation involves the movement of Circulation involves the movement of materials inside the cell, as well as the materials inside the cell, as well as the movement between parts of a multi-movement between parts of a multi-cellular organism.cellular organism.

• The function of the circulatory system is to The function of the circulatory system is to transport materials throughout the body.transport materials throughout the body.

• The system carries digested food (energy) The system carries digested food (energy) and oxygen to cells. It also carries wastes and oxygen to cells. It also carries wastes from the cells to the lungs, kidneys, and from the cells to the lungs, kidneys, and the skin.the skin.

The HeartThe Heart

• Composed almost entirely out of Composed almost entirely out of muscle called the muscle called the myocardiummyocardium..

• The The septumseptum prevents the mixing of prevents the mixing of oxygen-poor and oxygen-rich blood.oxygen-poor and oxygen-rich blood.

• The upper two chambers are called The upper two chambers are called the the atriaatria. The lower two chambers . The lower two chambers are called the are called the ventriclesventricles..

Blood VesselsBlood Vessels

• ArteriesArteries carry blood from the heart carry blood from the heart to the rest of the body.to the rest of the body.

• CapillariesCapillaries are small and bring are small and bring nutrients and oxygen to the tissues nutrients and oxygen to the tissues and absorbing carbon dioxide and and absorbing carbon dioxide and other waste products.other waste products.

• VeinsVeins return the blood back to the return the blood back to the heart.heart.

Blood PressureBlood Pressure

• Blood pressure is the force of the blood Blood pressure is the force of the blood on the arteries’ walls. This is what helps on the arteries’ walls. This is what helps the blood flow throughout your body.the blood flow throughout your body.

• The first or top number is the systolic The first or top number is the systolic pressure – the force felt when the pressure – the force felt when the ventricles contract.ventricles contract.

• The second or bottom number is the The second or bottom number is the diastolic pressure – the force of the blood diastolic pressure – the force of the blood when the ventricles relax.when the ventricles relax.

• An average adult’s blood pressure is An average adult’s blood pressure is 120/80.120/80.

BloodBlood

• Red blood cells (RBCs)Red blood cells (RBCs) transport transport oxygen. They have a protein that oxygen. They have a protein that binds to oxygen called hemoglobin.binds to oxygen called hemoglobin.

• White blood cells (WBCs)White blood cells (WBCs) attack attack foreign substances or organisms. foreign substances or organisms. Phagocytes, a type of WBC, “eat” Phagocytes, a type of WBC, “eat” foreign cells.foreign cells.

• PlateletsPlatelets are cell fragments that are cell fragments that when combined with when combined with plasmaplasma (the (the liquid part of blood), aid in clotting.liquid part of blood), aid in clotting.

Blood TypingBlood Typing

• http://www.youtube.com/watch?v=CduLOhttp://www.youtube.com/watch?v=CduLOqZb_XQqZb_XQ

Comprehension QuestionComprehension Question

• Platelets are used in clotting. What Platelets are used in clotting. What are red blood cells used for?are red blood cells used for?

A.A. Disease FightingDisease Fighting

B.B. ExhalationExhalation

C.C. Oxygen TransportOxygen Transport

D.D. Gas ExchangeGas Exchange

E.E. Cellular RespirationCellular Respiration

What Can Go Wrong What Can Go Wrong With the Circulatory With the Circulatory

System?System?

High Blood PressureHigh Blood Pressure

• Also known as “hypertension.”Also known as “hypertension.”• If blood pressure gets too high, the If blood pressure gets too high, the

heart needs to work harder to pump heart needs to work harder to pump the same amount of blood to the the same amount of blood to the body, which may weaken or damage body, which may weaken or damage the heart muscle and blood vessels.the heart muscle and blood vessels.

• Having high blood pressure increases Having high blood pressure increases the risk of heart attack and stroke.the risk of heart attack and stroke.

Heart AttackHeart Attack

• A heart attack occurs when one of the A heart attack occurs when one of the arteries near your heart becomes arteries near your heart becomes blocked, often due to artherosclerosis blocked, often due to artherosclerosis (high cholesterol in the arteries), and (high cholesterol in the arteries), and part of the heart muscle may begin to part of the heart muscle may begin to die due to a lack of oxygen.die due to a lack of oxygen.

• The symptoms are:The symptoms are:– NauseaNausea– Shortness of breathShortness of breath– Severe, crushing chest painSevere, crushing chest pain

Stroke and DVTStroke and DVT

• Blood clots can sometimes break free and get Blood clots can sometimes break free and get stuck in a blood vessel.stuck in a blood vessel.

• A stroke is when the blood clot gets stuck in a A stroke is when the blood clot gets stuck in a blood vessel leading to the brain. Brain cells blood vessel leading to the brain. Brain cells normally served by that blood vessel slowly die normally served by that blood vessel slowly die from a lack of oxygen, leading to a loss of brain from a lack of oxygen, leading to a loss of brain function in that area.function in that area.

• A deep vein thrombosis (DVT) is caused when a A deep vein thrombosis (DVT) is caused when a blood clot gets stuck in a blood vessel located blood clot gets stuck in a blood vessel located deep in the leg. These result in extreme pain in deep in the leg. These result in extreme pain in the area that may be warm to the touch, the area that may be warm to the touch, swelling of the leg, and redness in the area.swelling of the leg, and redness in the area.

DVT in the left leg.

Stroke

PreventionPrevention

• These disorders are easier to These disorders are easier to prevent than to cure.prevent than to cure.

• http://www.youtube.com/watch?v=zhttp://www.youtube.com/watch?v=zKsUZQsM6rkKsUZQsM6rk– ExerciseExercise– Sensible diet low in saturated fatsSensible diet low in saturated fats– Stop (or better yet, never start) Stop (or better yet, never start)

smokingsmoking

The Respiratory The Respiratory SystemSystem

RespirationRespiration

• The process of respiration for the organism is The process of respiration for the organism is similar to that for the cell, only on a larger similar to that for the cell, only on a larger scale. It uses oxygen to break down food scale. It uses oxygen to break down food molecules in order to release energy.molecules in order to release energy.

• The function of the respiratory system is the The function of the respiratory system is the exchange of gases between the blood of the exchange of gases between the blood of the circulatory system and the environment. It circulatory system and the environment. It takes in oxygen for cell respiration and takes in oxygen for cell respiration and transfers it to the blood. It also removes transfers it to the blood. It also removes carbon dioxide from the bloodstream and carbon dioxide from the bloodstream and releases it from the body.releases it from the body.

Parts of the Respiratory Parts of the Respiratory SystemSystem

• Air moves through the nose to a tube at the Air moves through the nose to a tube at the back of the throat called the back of the throat called the pharynxpharynx. Air . Air then moves into the then moves into the tracheatrachea (windpipe.) (windpipe.)

• The air moves down your trachea into your The air moves down your trachea into your lungslungs, which contain the , which contain the bronchibronchi that look that look like branches leading to the like branches leading to the bronchiolesbronchioles (smaller branches.)(smaller branches.)

• Eventually the air reaches the Eventually the air reaches the alveolialveoli (look (look like grape clusters) at the end of the like grape clusters) at the end of the bronchioles, which is where the blood and bronchioles, which is where the blood and air are side by side and the real work of the air are side by side and the real work of the system takes place.system takes place.

BreathingBreathing

• The The diaphragmdiaphragm is a large, flat muscle at is a large, flat muscle at the bottom of the chest cavity.the bottom of the chest cavity.

• When you breathe in, the diaphragm When you breathe in, the diaphragm contracts and flattens, making the chest contracts and flattens, making the chest cavity larger.cavity larger.

• When you exhale, the diaphragm relaxes When you exhale, the diaphragm relaxes and curves back up, making the chest and curves back up, making the chest cavity smaller.cavity smaller.

• Combined with atmospheric pressure and Combined with atmospheric pressure and how tightly sealed the chest cavity is, this how tightly sealed the chest cavity is, this is how you breathe.is how you breathe.

Comprehension Comprehension Question:Question:

•Which structure in the cell Which structure in the cell corresponds with the corresponds with the function of the human lungs?function of the human lungs?

What Can Go Wrong What Can Go Wrong With the Respiratory With the Respiratory

System?System?

AsthmaAsthma

• Inflammatory response in the Inflammatory response in the airways where the muscles tighten airways where the muscles tighten up, making it difficult to breathe.up, making it difficult to breathe.

• Causes attacks of wheezing, Causes attacks of wheezing, shortness of breath, chest tightness, shortness of breath, chest tightness, and coughing.and coughing.

• Can be brought on by Can be brought on by

exercise or allergies. exercise or allergies.

BronchitisBronchitis

• An inflammation of the lung An inflammation of the lung passages.passages.

• Usually follows a respiratory Usually follows a respiratory infection, causing extreme coughing infection, causing extreme coughing fits with lots of mucus.fits with lots of mucus.

• Affects the elderly, young children, Affects the elderly, young children, and a significant number of and a significant number of

smokers.smokers.

Cystic FibrosisCystic Fibrosis

• Genetic (inherited) disease.Genetic (inherited) disease.• Causes thick, sticky mucus to build Causes thick, sticky mucus to build

up in the lungs and digestive tract, up in the lungs and digestive tract, making it extremely difficult to making it extremely difficult to breathe.breathe.

The Effects of SmokingThe Effects of Smoking

• Three of the most dangerous substances Three of the most dangerous substances in cigarettes are in cigarettes are nicotinenicotine (addictive (addictive stimulant,) stimulant,) carbon monoxidecarbon monoxide (poisonous (poisonous gas,) and gas,) and tartar (known to cause cancer.) (known to cause cancer.)

• Can cause diseases such as lung cancer Can cause diseases such as lung cancer and emphysema (makes breathing very and emphysema (makes breathing very difficult.)difficult.)

• Studies indicate that the children of Studies indicate that the children of smokers are twice as likely to develop smokers are twice as likely to develop respiratory problems, such as asthma, respiratory problems, such as asthma, than children of non-smokers.than children of non-smokers.

The Skeletal and The Skeletal and Muscular SystemsMuscular Systems

The SkeletonThe Skeleton

• Supports the bodySupports the body• Protects internal organsProtects internal organs• Provides for movementProvides for movement• Stores mineral reservesStores mineral reserves• Site for blood cell formationSite for blood cell formation

Structure and Development Structure and Development of Bonesof Bones

• Bones are a solid network of living Bones are a solid network of living cells and protein fibers that are cells and protein fibers that are surrounded by calcium salts.surrounded by calcium salts.

• The skeleton of a newborn baby is The skeleton of a newborn baby is made up almost all out of cartilage, made up almost all out of cartilage, which is more flexible than bone. It which is more flexible than bone. It gradually changes into bone as you gradually changes into bone as you get older.get older.

Types of JointsTypes of Joints• Immovable (Fixed) JointsImmovable (Fixed) Joints

– Fused together, so they are unable to move. Fused together, so they are unable to move. – Example: bones that form your skullExample: bones that form your skull

• Slightly Moveable JointsSlightly Moveable Joints– These are able to move a little bit. These are able to move a little bit. – Example: joints between vertebraeExample: joints between vertebrae

• Freely Moveable JointsFreely Moveable Joints– These are able to move in one or more These are able to move in one or more

directions. directions. – Example: knee or hipExample: knee or hip

• LigamentsLigaments connect bones to each other. connect bones to each other.

Muscle TissueMuscle Tissue

• Skeletal MuscleSkeletal Muscle is usually attached to is usually attached to bones, so they help you move. For the bones, so they help you move. For the most part, you can control these muscles.most part, you can control these muscles.

• Smooth MuscleSmooth Muscle is found in your is found in your digestive system and blood vessels. You digestive system and blood vessels. You can’t control how they work.can’t control how they work.

• Cardiac MuscleCardiac Muscle is found only in the is found only in the heart. It’s sort of a mixture of skeletal heart. It’s sort of a mixture of skeletal and smooth muscle.and smooth muscle.

How Do Bones and Muscles How Do Bones and Muscles Work Together?Work Together?

• Skeletal muscles produce movement by Skeletal muscles produce movement by contracting, or pulling on body parts.contracting, or pulling on body parts.

• The muscles are attached to bone by The muscles are attached to bone by tough connective tissues called tough connective tissues called tendonstendons..

• Your muscles work in pairs or groups.Your muscles work in pairs or groups.• When you move your muscles, they pull When you move your muscles, they pull

on the tendons, that pull on the bones.on the tendons, that pull on the bones.

Comprehension QuestionComprehension Question

• All of the following are important All of the following are important roles of the skeletal system roles of the skeletal system EXCEPT:EXCEPT:

1.1. Protection of internal organsProtection of internal organs

2.2. Facilitation of movementFacilitation of movement

3.3. Storage of mineral reservesStorage of mineral reserves

4.4. Production of red blood cellsProduction of red blood cells

5.5. Regulation of body temperatureRegulation of body temperature

What Can Go Wrong What Can Go Wrong With the Skeletal and With the Skeletal and Muscular Systems?Muscular Systems?

Broken Bones/FracturesBroken Bones/Fractures

• Happen because a bone is unable to Happen because a bone is unable to handle the pressure put on it.handle the pressure put on it.

• http://video.about.com/orthopedics/Fhttp://video.about.com/orthopedics/Fractures-1.htmractures-1.htm

OsteoporosisOsteoporosis• Usually occurs in older people.Usually occurs in older people.• Thinning or weakening of the bone tissue and Thinning or weakening of the bone tissue and

loss of bone density over time, usually caused loss of bone density over time, usually caused by a lack of calcium and phosphate in the by a lack of calcium and phosphate in the bones.bones.

• Can lead to more fractures.Can lead to more fractures.• In children, a lower level of vitamin D can lead In children, a lower level of vitamin D can lead

to a softening of bone tissue as well. This is to a softening of bone tissue as well. This is called “rickets.” It can lead to a bowing out of called “rickets.” It can lead to a bowing out of the legs, the legs,

because the leg bones are so soft that because the leg bones are so soft that they can’t support the rest of the they can’t support the rest of the body properly.body properly.

The Difference Between The Difference Between Sprains and StrainsSprains and Strains

• SprainsSprains affect the affect the ligamentsligaments, which , which connect bone to bone. Symptoms include: connect bone to bone. Symptoms include: bruising, swelling, instability, and painful bruising, swelling, instability, and painful movement.movement.

• StrainsStrains affect the affect the muscles or tendonsmuscles or tendons, , usually from over-stretching. Symptoms usually from over-stretching. Symptoms include: pain, weakness, and muscle spasms.include: pain, weakness, and muscle spasms.

• Treatment is the same: RICE (rest, ice, Treatment is the same: RICE (rest, ice, compression, and elevate.)compression, and elevate.)

Excretory and Excretory and Digestive SystemsDigestive Systems

ExcretionExcretion

• The excretory system is made up of The excretory system is made up of the skin, lungs, and kidneys.the skin, lungs, and kidneys.

• Excretion is the elimination (removal) Excretion is the elimination (removal) of metabolic wastes from the of metabolic wastes from the cellscells..

• The skin does this by sweating The skin does this by sweating through sweat glands.through sweat glands.

• The lungs do this by exhaling carbon The lungs do this by exhaling carbon dioxide.dioxide.

KidneysKidneys

• Maintain homeostasis by:Maintain homeostasis by:– regulating the water content of the regulating the water content of the

blood (blood volume)blood (blood volume)– maintaining blood pHmaintaining blood pH– removing waste products from the removing waste products from the

bloodblood

• The kidneys filter the blood. What is The kidneys filter the blood. What is filtered out makes up urine. filtered out makes up urine.

Comprehension QuestionComprehension Question

• Which is NOT a role of the kidney?Which is NOT a role of the kidney?1.1. Removal of waste products from the Removal of waste products from the

bloodblood

2.2. Maintenance of blood pHMaintenance of blood pH

3.3. Regulation of water content of the Regulation of water content of the bloodblood

4.4. Maintenance of homeostasisMaintenance of homeostasis

5.5. Excretion of carbon dioxideExcretion of carbon dioxide

The Digestive SystemThe Digestive System

• Includes many organs that all work Includes many organs that all work together.together.

• Converts foods into simpler Converts foods into simpler molecules that can be absorbed and molecules that can be absorbed and used by the cells of the body.used by the cells of the body.

MouthMouth

• Your teeth do much of the mechanical Your teeth do much of the mechanical work of digestion. They cut, tear, and work of digestion. They cut, tear, and crush food into smaller pieces.crush food into smaller pieces.

• Saliva is released by the salivary Saliva is released by the salivary glands. This starts chemical digestion glands. This starts chemical digestion where enzymes break down the food.where enzymes break down the food.

• The chewed clump of food is called a The chewed clump of food is called a bolusbolus..

EsophagusEsophagus

• This is the tube that food goes down This is the tube that food goes down to reach the stomach.to reach the stomach.

• In order for the food to get to the In order for the food to get to the stomach, contractions occur called stomach, contractions occur called peristalsisperistalsis, squeezing the bolus in , squeezing the bolus in waves.waves.

StomachStomach

• Food from the esophagus empties Food from the esophagus empties into the stomach where both into the stomach where both chemical and mechanical digestion chemical and mechanical digestion occur.occur.

• The stomach holds hydrochloric acid The stomach holds hydrochloric acid so that it can further break down the so that it can further break down the food, turning it into a mixture called food, turning it into a mixture called chymechyme..

Pancreas and LiverPancreas and Liver

• The pancreas is a gland. It produces The pancreas is a gland. It produces hormones to regulate blood sugar, hormones to regulate blood sugar, produces enzymes to break down food, produces enzymes to break down food, and produces sodium bicarbonate to and produces sodium bicarbonate to neutralize stomach acid.neutralize stomach acid.

• The liver produces bile, which helps The liver produces bile, which helps dissolve fat. The gallbladder is right dissolve fat. The gallbladder is right next to the liver, and this is where bile next to the liver, and this is where bile is stored.is stored.

Small and Large Small and Large IntestinesIntestines

• The small intestine absorbs The small intestine absorbs nutrients. It is lined with little nutrients. It is lined with little projections (like fingers) called projections (like fingers) called villivilli, , creating a very large surface area.creating a very large surface area.

• The large intestine removes any The large intestine removes any remaining water from the chyme, remaining water from the chyme, leaving behind the feces which are leaving behind the feces which are removed by the anus at the end of removed by the anus at the end of the large intestine.the large intestine.

Comprehension QuestionComprehension Question

• Individuals who have had part, or Individuals who have had part, or even all, of their stomach removed even all, of their stomach removed can survive. Do you think the same can survive. Do you think the same individuals could survive without a individuals could survive without a small intestine? Explain your small intestine? Explain your answer.answer.

What Can Go Wrong What Can Go Wrong With the Excretory With the Excretory

and Digestive and Digestive Systems?Systems?

Urinary Tract Infection Urinary Tract Infection (UTI)(UTI)

• This is an infection that occurs This is an infection that occurs anywhere along the urinary tract anywhere along the urinary tract (bladder, kidneys, urethra, ureters.)(bladder, kidneys, urethra, ureters.)

• Women are more likely to get them, Women are more likely to get them, because their urethra is shorter than because their urethra is shorter than in men.in men.

• Symptoms include: pain or burning Symptoms include: pain or burning when urinating, bloody urine, back when urinating, bloody urine, back and/or abdominal pain or cramping.and/or abdominal pain or cramping.

HeartburnHeartburn

• This is when the acid from your This is when the acid from your stomach enters the esophagus, stomach enters the esophagus, causing pain and damage to the causing pain and damage to the esophagus lining.esophagus lining.

• This can occur because of a faulty This can occur because of a faulty esophageal sphincter (muscle that esophageal sphincter (muscle that keeps things closed) or due to eating keeps things closed) or due to eating certain foods.certain foods.

Celiac DiseaseCeliac Disease• Believed to be a genetic condition, occurring in Believed to be a genetic condition, occurring in

approximately 1 out of every 133 people in the approximately 1 out of every 133 people in the USA.USA.

• The body is unable to tolerate gluten, a protein The body is unable to tolerate gluten, a protein found in wheat, rye, and barley. The body actually found in wheat, rye, and barley. The body actually attacks the small intestine, removing the villi. attacks the small intestine, removing the villi. This prevents proper absorption of nutrients.This prevents proper absorption of nutrients.

• Symptoms include abdominal pain, nausea, Symptoms include abdominal pain, nausea, diarrhea, vomiting, extreme fatigue, joint pain, diarrhea, vomiting, extreme fatigue, joint pain, skin rash, dental and bone problems, and “tunnel skin rash, dental and bone problems, and “tunnel vision,” especially when the person has eaten vision,” especially when the person has eaten gluten.gluten.

• The only treatment is to follow a gluten free diet, The only treatment is to follow a gluten free diet, which can prevent symptoms from occuring.which can prevent symptoms from occuring.

Nervous SystemNervous System

Nervous System FunctionNervous System Function

• Coordinates the body’s response to Coordinates the body’s response to changes in its internal and external changes in its internal and external environments.environments.

• Contains cells called Contains cells called neuronsneurons that that transmit impulses (signals.)transmit impulses (signals.)

SynapseSynapse

• This is where one neuron can This is where one neuron can transfer an impulse to another cell.transfer an impulse to another cell.

• Neurotransmitters are chemicals Neurotransmitters are chemicals used by the neuron to transmit an used by the neuron to transmit an impulse across a synapse.impulse across a synapse.

Central Nervous SystemCentral Nervous System

• Brain and Spinal CordBrain and Spinal Cord• Wrapped up in tissue layers called Wrapped up in tissue layers called

meninges. meninges. • Cerebrospinal fluid “bathes” them Cerebrospinal fluid “bathes” them

and protects the brain and spinal and protects the brain and spinal cord.cord.

BrainBrain• Cerebrum: responsible for voluntary Cerebrum: responsible for voluntary

activities of the body, including activities of the body, including intelligence, learning, and judgment.intelligence, learning, and judgment.

• Cerebellum: coordinates and Cerebellum: coordinates and balances the muscles.balances the muscles.

• Brain Stem: controls blood pressure, Brain Stem: controls blood pressure, heart rate, breathing, and heart rate, breathing, and swallowing.swallowing.

Spinal CordSpinal Cord

• Main communications link between Main communications link between the brain and rest of the body.the brain and rest of the body.

• Some information, such as reflexes, Some information, such as reflexes, are processed directly in the spinal are processed directly in the spinal cord. Reflexes allow your body to cord. Reflexes allow your body to respond to danger immediately, respond to danger immediately, without spending time thinking without spending time thinking about a response.about a response.

Peripheral Nervous Peripheral Nervous SystemSystem

• Consists of nerves and associated Consists of nerves and associated cells that are not part of the brain or cells that are not part of the brain or spinal cord.spinal cord.

• Sensory division: transmits impulses Sensory division: transmits impulses from sense organs to the central from sense organs to the central nervous system.nervous system.

• Motor division: transmits impulses Motor division: transmits impulses from the central nervous system to from the central nervous system to muscles or glands.muscles or glands.

Motor DivisionMotor Division

• Somatic Nervous System: Regulates Somatic Nervous System: Regulates activities that are under conscious activities that are under conscious control, such as movement of control, such as movement of muscles.muscles.

• Autonomic Nervous System: Autonomic Nervous System: Regulates activities that are Regulates activities that are automatic or involuntary, such as automatic or involuntary, such as heartbeat and digestion.heartbeat and digestion.

What Can Go Wrong What Can Go Wrong With the Nervous With the Nervous

System?System?

Multiple SclerosisMultiple Sclerosis• Auto-immune disease (body attacks Auto-immune disease (body attacks

itself.)itself.)• Caused by inflammation and damage to Caused by inflammation and damage to

the myelin sheath of the neuron, slowing the myelin sheath of the neuron, slowing down or stopping impulses.down or stopping impulses.

• Symptoms occur throughout the entire Symptoms occur throughout the entire body.body.

• Affects females more than males between Affects females more than males between the ages of 20-40 years old, and gets the ages of 20-40 years old, and gets worse over time.worse over time.

Drugs and the Nervous Drugs and the Nervous SystemSystem

• http://www.youtube.com/watch?v=3http://www.youtube.com/watch?v=3FtNm9CgA6UFtNm9CgA6U

• http://www.youtube.com/watch?v=1jhttp://www.youtube.com/watch?v=1jLU0oSHs6QLU0oSHs6Q

Endocrine SystemEndocrine System

Endocrine SystemEndocrine System

• Made up of glands that release their Made up of glands that release their products into the bloodstream.products into the bloodstream.

• These products broadcast messages These products broadcast messages throughout the body.throughout the body.

HormonesHormones

• Chemicals that travel through the Chemicals that travel through the bloodstream and affect the activities bloodstream and affect the activities of other cells.of other cells.

• Cells that have a receptor for a Cells that have a receptor for a particular hormone are called target particular hormone are called target cells.cells.

• The body’s response to hormones is The body’s response to hormones is slower and longer-lasting than nerve slower and longer-lasting than nerve responses.responses.

GlandsGlands

• Exocrine glands:Exocrine glands: release secretions release secretions through ducts (tubes)through ducts (tubes)– Ex. Sweat, tears, digestive juicesEx. Sweat, tears, digestive juices

• Endocrine glands:Endocrine glands: release release secretions (hormones) directly into secretions (hormones) directly into the bloodstreamthe bloodstream

Pituitary GlandPituitary Gland

• Secretes nine hormonesSecretes nine hormones• Directly regulates many body Directly regulates many body

functions and controls the actions of functions and controls the actions of several other endocrine glands.several other endocrine glands.

• Hormone: growth hormoneHormone: growth hormone

HypothalamusHypothalamus

• Controls the pituitary glandControls the pituitary gland• Produces chemicals called Produces chemicals called

“releasing hormones” that stimulate “releasing hormones” that stimulate the pituitary gland to release its own the pituitary gland to release its own hormones.hormones.

Thyroid GlandThyroid Gland

• Regulates body’s metabolism.Regulates body’s metabolism.• Hormones: thyroxin and calcitoninHormones: thyroxin and calcitonin

Parathyroid GlandsParathyroid Glands

• Works together with the thyroid Works together with the thyroid gland to maintain homeostasis in gland to maintain homeostasis in blood calcium levels.blood calcium levels.

• Hormone: parathyroid hormone Hormone: parathyroid hormone (PTH)(PTH)

Adrenal GlandsAdrenal Glands

• Adrenal Cortex produces Adrenal Cortex produces corticosteroids that help with corticosteroids that help with excretion.excretion.

• Adrenal Medulla releases Adrenal Medulla releases epinepherine and norepinephrine, epinepherine and norepinephrine, causing the “fight or flight” response causing the “fight or flight” response to stress.to stress.

PancreasPancreas

• Keeps the level of glucose in the Keeps the level of glucose in the blood stable.blood stable.

• Hormones: insulin and glucagonHormones: insulin and glucagon

Reproductive Reproductive Glands/GonadsGlands/Gonads

• Involved in the production of Involved in the production of gametes and secretion of sex gametes and secretion of sex hormoneshormones

• Females: ovariesFemales: ovaries• Males: testesMales: testes