Chapter 6 The Human Organism and the Importance of Nutrition Topics: Nutrition and Nutrients: the Digestive System Respiration and Energy: Respiratory System Transporting Nutrients: The Cardiovascular system Fighting Disease: The Lymphatic System Elimination of Waste: The Urinary System

What it is and how to balance it Nutrition What it is and how to balance it

Nutrients A nutrient is a substance found in food that is used by the body to meet important needs In other words, it’s the stuff in food that we need. Some nutrients give us Some nutrients are useful in other ways. Energy

6 components to nutrition 1. Carbs (carbohydrates) 2. Protein 3. Fats (lipids) 4. Vitamins 5. Minerals 6. Water Energy Health

Carbs (carbohydrates) For energy Carbs (carbohydrate) go by many names Sugar or starch Simple sugars complex carbohydrates, like starch, glycogen and cellulose Starch sources: grains, pasta potatoes Sources of sugar: nearly everything!!!

Protein builds and maintains body tissue Not all proteins are alike. creates all the structures of our bodies hair, muscles, fingernails Not all proteins are alike. Proteins are made up of amino acids.

Protein Essential Amino acids are a fundamental part of our diet. 10 of the 20 amino acids are made by the human body The other 10 cannot and must be eaten. ***These other ten are "essential amino acids" They can easily be provided by a balanced diet.*** Protein as Energy source Inefficient use of protein because It must be used immediately or the body converts protein to fat

Fats (lipids=fats, oil, waxes, sterols) Contain twice the energy per gram as either carbs or protein. Important for getting your vitamins Vitamins A, D, E and K require fats You must eat fats along with these vitamins for your body to absorb them They are “fat soluble” ( as opposed to water soluble)

Fats In our body Fats are used for Energy Storage Excess carbs and glucose are converted to fats. Fat is also needed to: cushion all organs insulate against heat loss. Fat becomes harmful in excess! Stresses bones, muscles, heart and emotions

Cholesterol Cholesterol is a type of fat that is found in most animals Cholesterol is found in fatty meat Cholesterol Cholesterol is a type of fat that is found in most animals It is needed for many processes, including: Maintaining cell membrane flexibility Making hormones Cholesterol is: Present in animal based foods Not present in plant based foods Your liver produces all you need You don’t need to eat any extra! Too much cholesterol can clog up your arteries!

Vitamins and Minerals Both are substances needed in tiny amounts for metabolic processes Minerals are inorganic Digesting food, building/repairing tissue, transporting materials etc Are you getting enough? Marked on food labels as % DV Percentage daily value

Vitamins and minerals Are you getting enough? carefully plan your diet to include: dairy foods, veggies, meats and fortified foods Fortified = vitamins/minerals added (ie. Iodine in salt, vitamin D in milk etc.) Or take a multivitamin that supplement your diet. Does not replace a healthy diet

Focus Vitamins and minerals Tough vits and mins to get enough of in your diet. Calcium What It Does Keeps bones and teeth healthy Helps nerves function Regulates your heartbeat Needed to make blood clot Where you get it Dark leafy greens, beans, dairy

Focus Vitamins and minerals Vitamin D What it does forms bones and teeth Helps immune function Where to get it Sun bathing Vitamin D fortified milk Salmon with bones/Sardines Eggs and egg substitutes

Focus on Vitamins and Minerals Arrrghh! If you don’t get any vitamin C, you could get SCURVEY! Vitamin C What does it do? Heals wounds and broken bones Smokers should take 175% DV Improves immunity Where do I get it? Fruits (esp. citrus), broccoli, cabbage Then your teeth might fall out!

Focus Vitamins and minerals Vitamin B12 What it do Helps absorb food Helps nervous system Memory Keeps blood cells healthy Where you get it Liver Meat in general Milk Fortified cereals

Energy from Food The amount of energy in food can be measured in: Dietary Calories (Cal) technically, a capital “C” dietary calorie is a kilocalorie, 1000 small “c” physical calories, but we will use the common approach and just call them Calories. or Kilojoules (kJ) One kJ = 4.19 Cal So, if you know how many Calories a food has, just multiply by 4 to find its approximate kilojoules.

Why two different measures? In Canada we are supposed to use kilojoules, in accordance with international standards In the United States they mostly use Calories, so lots of our textbooks and cookbooks list food energy in Calories.

Energy from food Only three of the six parts of your diet give you energy Carbohydrates 4 cal/g Proteins Fats 9 cal/g

Energy needs You need energy for everything your body does and even for your mind’s thoughts! The basic energy requirements are keep your heart, brain and other organs going. In addition any exercise you do requires energy based on Intensity of activity Your body mass

Energy in = Energy out? The amount of energy we get from food should be equal to the amount of energy that we use. If we get less energy from our food, we begin to starve. If we get more energy from our food than we use, then our body stores the extra energy as fat. Energy

In other words… If you use up 2000 Calories (8000 kJ) in a day by your activities… Then you should eat food containing about 2000 Calories (8000 kJ) in order to replace your energy

How much do you need Varies with age and sex Adolescent girl : 1800-2400 Cal (7200-9600 kJ) Adolescent boy: 2200-3200 Cal (8800-12800kJ)

What do you think this diagram means? Everything is related to nutrition What you eat, exercise, how well you care for yourself.

Another pyramid: the food pyramid Eat only a little of the stuff on top: Sweets and carbohydrates Eat a bit more meat and dairy Eat even more fruit and vegetables Eat mostly foods with lots of grain and fibre, like bread, cereal, rice and

Eat… Lots of grain and fibre-rich food. Quite a bit of fruit and vegetables. Some meat and dairy. Just a little bit of dessert.

Filling in the Calories Used Table Activity # hours Cal /h Calories used Kilojoules Sleeping, Lying down 60 Sitting, Watching TV 90 Standing 120 Light Exercise 170 Sports, Heavy Exercise 300 TOTAL 8 h 10 h 2 h 3 h 1 h 480 900 240 510 300 2430 1920 3600 960 2040 1200 9720 Conclusion : Yesterday I used approximately 2430 calories of energy (or about 9720 kilojoules)

Cereal / Milk Toast / butter Egg Bacon 1 2 3 110 65 75 35 110 130 75 Food (Breakfast) Servings eaten Calories per serving Calories consumed Kilojoules consumed TOTAL Cereal / Milk Toast / butter Egg Bacon 1 2 3 110 65 75 35 110 130 75 115 440 520 300 460 430 1720

Exercises and Assignments Text Book Read pp. 159 to 166 Do page 194, question #1 to 3 Workbook Do pages 89, 90, 91 and 92

The Digestive System -a one way tube through the body Topics: Digestive Tract vs. Glands Digestion and absorption The organs of the tube

Two Main Parts of Digestive System I. The Digestive Tract 1) Mouth Ingests and chews food 2) Pharynx Forms food into a bolus & swallows 3) Esophagus Carries food to the stomach 4) Stomach Churns food into chyme 5) Small Intestine Absorbs nutrients from food 6) Large Intestine Absorbs water from waste 7) Rectum & Anus Eliminate waste food solids II. The Digestive Glands A) Salivary Glands Secrete saliva B) Gastric Glands Secrete stomach acid, mucus and pepsin C) Liver (with gall bladder) Secretes bile D) Pancreas Secretes pancreatic juice E) Intestinal Glands Secretes digestive enzymes & mucus

Digestion Your digestive system digests two ways Chemically Acids and enzymes react with foods to release their nutrients Physically/Mechanically Food is smooshed, torn and broken down into smaller pieces to releases nutrients

Absorption After food has been digested Nutrients from food leave your digestive tract And are absorbed into your blood

Digestive Associated Tract Glands & organs 2 1 A 1 The Mouth Pharynx (AKA:oral cavity) Pharynx Esophagus Stomach Small intestine (duodenum) (jejunum) (ileum) Large intestine (Ascending colon) (Transverse colon) (Descending colon) (Sigmoid colon) Rectum Anus Salivary glands (saliva) Gastric glands (stomach lining) (digestive juices) (acid & enzymes) Liver (bile) Gall Bladder (bile storage) Pancreas (pancreatic juice) Intestinal Glands Appendix (no function) Amylase 3 A 2 B 3 Pepsin Acid B C 4 C 4 5 Bile D Pancreatic Juice 5 D mucus 6 6 * E 7 * 7b 7 7b

Organs of the tube: 1. Mouth Mechanical digestion (physical breakdown) Teeth Chemical digestion (digestive enzymes) Saliva Under control of nervous system Contains: Lysozyme (antibacterial enzyme) Amylase (breaks down starch) Teeth Palate Uvula Salivary Gland Tongue

2. The Pharynx The pharynx is your throat. It determines whether we are breathing or swallowing We can’t do both at the same time A small muscular flaps, the uvula and the epiglotis control this. When we are breathing, they open a passage from our nose to our lungs. When we swallow, they close off the lungs, and force the food into our esophagus Uvula Epiglottis Food Air

3. Esophagus Tube that pushes bolus from the mouth to the stomach bolus = food clump The pushing is done by Peristalsis (click on word for animation) wave of muscle contractions Peristalsis pushes our food through the entire digestive system Heartburn is stomach acid burning the bottom of the esophagus

4. The Stomach Mechanical digestion in the stomach: Stomach muscles churn to produce chyme Chyme is mushed up food in stomach Chemical Digestion in the stomach: Gastric glands in the stomach lining secrete mucus and hydrochloric acid. Acid also activates release of pepsin Ulcers : Painful hole in stomach caused by excess acid or bacteria

5. The Small Intestine Starts right after the stomach Many enzymes and chemicals break down food Enzymes and chemicals are injected from the pancreas and liver ABSORBS nutrients. Small intestine is lined w/villi (tiny projections) covered w/microvilli Peristalsis pushes bolus along to large intestine

The Pancreas (a Gland) Pancreas – gland just below the stomach Pancreatic juice neutralizes stomach acid Works like “baking soda” to get rid of excess acid. Produces enzymes (like amylase) that break down macromolecules The Pancreas also releases insulin into blood.

The Liver (a Gland) Liver – large organ just above the stomach Produces bile (breaks down fat) Also vital for removal of toxins from body

6. The Large Intestine Recovers water (absorbs it back into the blood) Forms and stores feces (waste) Microbial fermentation to digest indigestible foods (cellulose/wood) Pushes waste to rectum by peristalsis

7. The Rectum The rectum holds feces until they leave the anus The anus is a sphincter muscle When you go #2 the sphincter relaxes When you hold it, the sphincter contracts Peristalsis pushes feces out of your body Anus

Large Intestine (colon) Large intestine Small Intestine

Organs of the Digestive Tract major organs are numbered, connections are not Digestive Tract organ connection Function connects 1. Mouth mechanical digestion 2. Pharynx Epiglottis mouth  esophagus 3. Esophagus moves food bolus Cardiac sphincter esophagus  stomach 4. Stomach digestion Pyloric valve stomach  small intestine 5. Small intestine digestion absorbs nutrients ! Cecum small intestine  large 6. Large intestine absorbs water 7. Rectum holds feces until released. Anal sphincter Rectumoutside

Glands of the Digestive System What the glands & organs secrete: Salivary glands amylase digests starch (in mouth) lysozyme kills bacteria Gastric Glands acid dissolves foods (in stomach lining) pepsin digests protein mucus protects stomach Liver & gall bladder bile digests fats Pancreas pancreatic neutralizes acid juice helps digest fats & carbs insulin absorbs carbs into blood into blood Mouth Stomach Intestines

Exercises and Assignments Text Book Read pages 167 to 171 Do Questions 4 and 5 on pages 194 to 195 Workbook Do 93, 94, 95, 96, 97, 98

The Respiratory System Topics: Respiration? Parts of the resp sys Breathing

energy Respiratory System oxygen Respiration is the process by which we get from nutrients. Carbs, Fats and Proteins can provide us with energy if they are OXIDIZED by mitochondria or our cells. To oxidize these nutrients, we need Getting this oxygen into our blood is the job of the respiratory system. energy oxygen

What is Respiration? Respiration is… Respiratory system consists of: A) the process by which food is oxidized B) the Process where Oxygen (O2) is exchanged for Carbon Dioxide (CO2) Respiratory system consists of: Nose, pharynx, larynx, trachea, bronchi, bronchioles, lungs, ALVEOLI

Parts of the Respiratory System 1. Nasal Passages. They filter the air with hairs, and they warm and moisten the air with mucus. Nasal Passage Pharynx Nose Mouth

Parts of the Respiratory System 2. Pharynx = passage way to the trachea (windpipe) and to the esophagus. Epiglottis = door that opens/closes trachea The pharynx is a crossing point between digestive and respiratory systems Pharynx Nose Larynx Mouth Epiglottis

Parts of the Respiratory System 3. Larynx = vocal cords sit at top of trachea. They carry air and produce sound (voice) Pharynx Larynx Nose Trachea Mouth Epiglottis

Parts of the Respiratory System 4. Trachea= AKA windpipe, tube that flows from larynx to bronchi. It further filters the air, and sweeps dirt upwards using hair-like cilia Pharynx Nose Larynx Trachea Mouth Lung Epiglottis

Parts of the Respiratory System 5. Bronchi (sing. Bronchus) are two air passages into lungs. They split into many smaller bronchioles. Pharynx Nose Larynx Trachea Mouth Lung Bronchiole Bronchus Epiglottis Alveoli Bronchioles Diaphragm Capillaries Edge of pleural membrane

Parts of the Respiratory System 6. Lungs = Spongy, elastic organs in the ribcage. Alvioli: inside the lungs are air sacs w/ capillaries that exchange O2 & CO2 (350 million of them) Alvioli are the FUNCTIONAL UNIT of resp. sys. Pharynx Nose Larynx Trachea Mouth Lung Bronchiole Bronchus Epiglottis Alveoli Bronchioles Diaphragm Capillaries Edge of pleural membrane

Gas Exchange In alveoli, O2 diffuses across capillaries and CO2 diffuses out Inhale: 21% O2 0.04% CO2 Exhale 15% O2 4% CO2 Alveoli Bronchiole Capillary

How do we Breath? Diaphragm = muscle that pulls down & expand lungs Air exhaled Air inhaled Rib cage descends Rib cage rises Diaphragm Diaphragm Inhalation Exhalation

How is breathing controlled? The Brain Stem (AKA: medulla oblongata) controls breathing by detecting CO2 ( not O2). If blood is high in CO2, you breathe faster.

Assignments and Exercises Text Book Read pages 172 to 176 Do Questions 7, 8 and 9 on page 195 Workbook Do pages 99, 100, 101 and 102

Blood Lymph Blood and Lymph Blood and lymph are two fluids that circulate though our bodies. Each fluid has its own system of vessels to carry it from place to place. Blood Lymph

BLOOD Red blood cells, White blood cells, Platelets and Plasma

4 Litres 6 Litres About Blood Blood is the only fluid tissue It is red and viscous (thicker than water) You have between 4 and 6 litres of blood Women have closer to four, men closer to 6 Blood is made of: Blood Plasma (the liquid part) Formed elements (the more solid part) including: Red Blood Cells (Erythrocytes or RBCs) White blood cells (Leucocytes or WBCs) Platelets 55% 45%

Blood can be separated with a Centrifuge The centrifuge spins a test tube of blood around. The heavy parts (RBCs) move to the bottom of the tube The light parts (blood plasma) go to the top of the tube Medium density parts (WBCs and platelets) end up in the middle of the test tube

Purposes of blood parts The blood plasma carries dissolved nutrients and/or waste materials White blood cells (AKA: WBCs or leucocytes ) help fight infections. We will look at WBCs in more detail when we study the lymphatic system. Platelets help our blood to clot, to seal leaks in our blood vessels and start tissue repair. Red blood cells (AKA: RBCs or erythrocytes) carry oxygen to all parts of the body

Blood Types Uses of blood typing Properties of blood help with: Paternity suits Forensic science Health problems

More on Erythrocytes (R.B.C.s) Substances on the surface of blood cells RBCs contain antigens Which determine your blood type 4 main blood types: A, B, AB and O There is another Substance (Rhesus) which is present in some people (the Rh factor) 2 minor blood types: If you have Rh factor it you are + If you don’t you are – Example blood types: Mr Taylor is B+ Mr MacKechnie is O- Other people can be: AB+, AB-, A+, A-, B- and O+ Total of 8 blood groups Substance A only Substance B only Both Substances No Substances

The most common blood type in North America is O+ The 8 Standard Blood Groups do not copy this chart. I will show you a faster way later Blood Type % Antigens Antibodies Can give blood to Can receive blood from AB+ 3% A, B, Rh None anybody AB– 1% A, B Rh AB+, AB– A–, AB–, B–, O– A+ 34% A, Rh B AB+, A+ A+, A– O+, O– A– 6% A B, Rh AB+, AB–, A+, A– A–, O– B+ 8% AB+, B+ B+, B–, O+, O– B– AB+, AB–,B+, B– B–, O– O+ 40% AB+, B+, A+, O+ O+, O– O– 7% none The rarest blood types in North America are AB- and B- The most common blood type in North America is O+

Immune System of the Blood Your immune system tries to destroy invading cells. It does this by producing chemicals called antibodies Usually this is a good thing. Invading cells often make us sick BUT… It may cause problems if you ever need a blood transfusion. You might produce antibodies against the blood cells you receive in a transfusion!

A Type A person has Substance A (the A-antigen) on their blood cells A Type A person can also produce an “Anti-B” chemical called the “B-Antibody” which will destroy any blood cell that has Substance B (the B-antigen) on it.

“Attack of the Antibodies” Chemical warfare of blood: Type A people produce anti-B chemicals that can destroy B-type blood cells AKA: B antibodies Type B’s produce anti-A chemicals AKA: A antibodies AB’s have no attack chemicals AKA: no antibodies O’s have both anti-chemicals. AKA: A and B antibodies Each blood type is also Rh+ or Rh- (positive or negative) Same system as blood types Rn positive has no Rh antibodies Rh negative produces Rh antibodies

Blood Transfusion Rules Recipients: Type A welcomes type A and type O blood B’s welcome in B and O blood AB’s welcome all blood types O’s reject all blood except for their own type. Donors: A’s can donate to A and AB types B’s can donate to B and AB AB’s donate to AB only O’s can donate to all Rh factors Positive can only donate to other positives. Negative can donate to both. Copy diagrams Additionally: Anyone can donate blood to, or receive blood from their own type

Transfusions… “Clumped” Blood Click on top picture and scroll down to the “Blood typing” section and show the agglutination animation on the left. Antibodies present in the recipient must not match the antigens (blood type) of the donor. Clumping will occur. Antibodies attach to matching antigens “Clumped” Blood Click on picture at right and play the “Blood Typing” game.

Assignments and Exercises Text Book: Read pages 177 to 181 Do questions 10, 11, and 12 on pages 195 and 196 Workbook: Do pages 103, 104, 105 and 106

The Cardiovascular System A.K.A: Circulatory System Topics the heart Circulation blood vessels blood types

Your Heart The size of your fist Mostly muscle 4 hollow chambers 2 Atria (plural of Atrium) upper chambers 2 Ventricles lower chambers Pericardium protective sac around the heart Septum wall separating heart’s chambers

Left and Right sides of the heart Most diagrams of the heart show the left and right sides reversed This is deliberate! You are viewing the heart from in front, so what you see on the left is actually the right side. Right Side Left Side

Blood Flow Through the Heart Blood flow is one way Atria accept blood and pump it into (load) ventricles Atria are weak pumps Ventricles pump the blood out of the heart. Ventricles are stronger pumps Valves prevent back flow of blood Keep it going one way. CV Diastole CV Systole

Circulation: 2 types Pulmonary circulation Systemic circulation From heart to lungs CO2 leaves blood, O2 enters blood. Systemic circulation Oxygen rich blood is pumped to the whole body Oxygen poor/ CO2 rich blood is returned

Heart Beat 2 sets of muscles fibers Atrial and ventrical Sinoatrial node in right atrium controls pace of heart Natural pacemaker

Blood vessels Artery The Cardiovascular system is a closed system from arteries to capillaries and back through veins Arteries From heart to tissues Carry oxygenated blood (rich in oxygen) Except pulmonary arteries which carry deoxygenated blood to the lungs. Arteries are thick walled. Because blood is under high pressure

Blood vessels Capillaries Capillaries Between arteries and veins Gas and nutrient exchange Capillaries are the Functional units of circulatory system Blood cells pass single file through capillaries

Blood vessels Vein Veins Carry blood back to the heart. Carry deoxygenated blood (lots of CO2) Except pulmonary veins which carry oxygenated. Thin walled Not much pressure. Valves in the veins keep blood from flowing backwards.

Body movements help push blood through the veins

Blood Pressure Measured with a sphygmomanometer Systolic pressure (great bonus question) Systolic pressure force felt when ventricles contract Diastolic pressure force felt when ventricles relax Average blood pressure is 140/90 Average tap pressure is 3000!

Circulatory System Disorders Atherosclerosis fat deposits in arteries Root cause of most disorders, high blood pressure, heart attacks and strokes.

Circulatory System Responses Your circulatory system has to respond to different stimuli: Example 1. When you exercise Your body needs more oxygen & nutrients Your heartbeat increases to speed circulation Some blood vessels expand, other close up Blood is directed towards organs that need it the most (like your muscles and lungs) Your respiratory system is stimulated so you breathe faster. Blood is directed away from organs that are not exercising (like your brain and parts of your digestive system.)

Example 2: When you are hot Blood flow is directed towards the skin Capillaries in the skin open up, allowing heat to be transferred to the skin. When you are hot, your skin often looks pinker because of this. Example 3: When you are cold Blood flow is directed towards vital organs to keep them warm. Capillaries in the skin close to reduce heat loss. When you are cold, you skin often looks pale.

Example 4: When you are nervous or afraid… Your adrenal glands produce adrenalin, which stimulates your circulatory system Your heartbeat and blood pressure increase, so you are ready to react. Example 5: When you are bleeding… Platelets in you blood start producing a stringy protien. This stringy substance traps blood cells forming a clot, that plugs the broken blood vessels. A large clot on the surface becomes a scab, that covers the wound and speeds up healing

Assignments and Exercises Text book: Read pages 182 to 186 Do questions 13, 14 and 15 on page 196 Workbook: Do pages 107, 108, 109 and 110

Extracellular fluid is a clear liquid that surrounds our cells. Lymphatic System A network of vessels that: Removes extracellular fluid and returns it to the Cardiovascular system. Absorbs fats and fat soluble vitamins from intestines Is home to many immune cells, including White Blood Cells. Extracellular fluid is a clear liquid that surrounds our cells. WBCs are actually made in the bone marrow, but are stored in the lymphatic system.

The lymphatic system “parallels” the cardiovascular system. Tonsils (large nodes) Vein The lymphatic system “parallels” the cardiovascular system. Its set of vessels, called lymph ducts, are similar to veins and capillaries. It has nodes, small organs which filter lymph, and where WBCs fight infections. Thymus Nodes (armpit) Bone marrow Nodes Spleen Lymph ducts Intestines Nodes Lymph ducts

Lymphatic system (cont) The yellowish fluid of the lymphatic system You have 1 or 2 litres of lymph in your body Contains: lots of fat, fluid, proteins, immune cells and wastes. Lymph nodes… Filter lymph Location of WBC activity.

White Blood Cells (WBCs / Leucocytes) and the Immune System 99.8% of our blood cells are Red Blood Cells that help carry oxygen. 0.2% are White Blood Cells (WBC) that fight infection. Although WBCs are found in the blood, they are more concentrated in the lymphatic system Most blood cells come from bone marrow. WBCs “eat” invading bacteria and viruses (phagocytosis) They can also kill infected cells by triggering their “self destruct sequence” (apoptosis)

White Blood Cells (Leucocytes) (AKA leukocytes) Attack intruders #s increase with infection in body Several varieties Contain nuclei 1 WBC to 700 RBCs Most live only a few days Produced in white bone marrow

Varieties of blood cells (FYI only) Don’t Copy RBCs WBCs Platelets

Platelets and Blood Clotting Platelets are Plasma proteins and cell fragments. Platelets make blood clot. They stick to damaged blood vessels they release clotting factors (coagulate blood) Optional Information: Calcium and vitamin K aid in creating thrombin Thrombin is an enzyme that converts fibrinogen into sticky mass of fibrin (AKA a scab)

Assignments and Exercises Text book: Read pages 187 to 190 (top) Workbook: Do pages 111, 112, 113, 114

The Urinary System and the Elimination of Waste. Waste is eliminated in many ways in our body: The digestive system excretes solid wastes that come from our food. The lungs eliminate CO2 and some other volatile wastes. The sweat glands help eliminate some dissolved wastes. But the most important system for eliminating dissolved or liquid wastes is the urinary system.

other wastes, excess salt & minerals Excretion Cells produce excess salt, CO2 and urea Skin excretes salt, water and a little urea Lungs excrete CO2 But it’s the Kidneys that filter out urea and other toxins Dirty Blood In Clean Blood Out Urine Water,urea, other wastes, excess salt & minerals from Renal Artery through Renal Vein through ureter to bladder

The Kidneys Kidneys are blood filters Renal artery enters kidney Cleaned blood leaves through renal vein The toxins leave the kidneys through the ureter to the urinary bladder Renal Artery Kidney Renal Vein Ureter

Enrichment How the Kidneys Work This section contains advanced material about how kidneys filter urea from our blood. If you aren’t interested in this, you can skip to: control of kidney function

Kidney Structure Shown cut in ½, the outer part is the renal cortex, inner is the renal medulla Functional unit of the kidney is the nephron filters out toxins and nutrients then reabsorbs only nutrients

The Nephron/Filtration Steps:1st Artery, 2nd Bowman’s capsule, 3rd the loop of Henle and 4th Blood leaves Vein/Urine goes to bladder. Nephrons are tiny, almost microscopic!

Artery carries blood to… Bowman’s capsule through the glomerulus. Pressurized capillaries remove or filter sugars, salts urea etc. Collecting tube then passes filtrate on to the Loop of Henle. Amino acids, glucose and 99% of water is reabsorbed into the blood by capillaries. Blood and waste separate Concentrated urine and salts are then secreted through ureter Blood leaves thru vein 3 a 2 4 1 b

Control of Kidney Function Controlled by composition of blood so… it’s important in Homeostasis of blood Maintains salt concentration, and pH Can you mess with your kidneys? Coffee and alcohol are diuretics…. They make your kidneys work harder. Diabetes and Heart Disease Make your kidneys more susceptible. Excess Medications Many medications contain toxic substances. Too much medicine might hurt your kidneys. Homeostasis means keeping everything in balance.

Mechanized Homeostasis Dialysis is what you need if your kidneys fail: blood is removed pumped through “hemodialyzer” filters (artificial kidneys) and replaced.

Summary Notes When we oxidize proteins, our cells produce a waste material called urea. We must excrete this excess urea, or it will become toxic. Our kidneys filter the urea from our blood, and excrete it as urine. If your kidneys fail, you might need dialysis

Assignments and Exercises Text Book: Read pages 190 to 193 Workbook: Do pages 115 to 116

Pathways of Nutrition Cardiovascular System Lymph Food Urinary System Digestive System In Out Nu Ur Cardiovascular System CO2 O2 Air (oxygen) Respiratory System CO2 Ur Respiratory System O2 Nu In Out Cells (Mitochondia)

End of Chapter 6 Pre-test Review Re-read Chapter 6 (pp.159 to 193) If you have read this before, you can just skim this time, looking for the highlights. If you haven’t read this before, read it carefully! Workbook pages 117 to 120

End of Chapter. Pre-test Review Re-read Chapter 6 (pp.159 to 193) If you have read this before, you can just skim this time, looking for the highlights. If you haven’t read this before, read it carefully! Workbook pages 117 to 120 This reviews the whole chapter, from nutrition to excretion, including: Digestive system & nutrition Cardiovascular System & blood Respiratory system Lymphatic System & lymph & immune cells Urinary System & urine

Answers to Workbook page 117 1. a) cardiovascular system, b) lymphatic system, c) digestive system, d) respiratory system, e) urinary system 2. Oxygen • Cellular waste • from blood to cells Carbon dioxide • from cells to blood Nutrients •

Answers to Workbook page 118 3 A) Respiratory, urinary, digestive system, skin(must give 2 of4) B) Digestive system C) Cardiovascular system (also accept circulatory system) D) Lymphatic system (also accept immune system) 4. Element Found in Blood Found in lymph White Blood Cells  Red Blood Cells Water Cell Waste Nutrients Platelets

Answers to Workbook page 118 Organs System Lungs Respiratory System Stomach Digestive System Bladder Urinary System Heart Cardiovascular System Veins Pancreas Kidneys Lymph nodes Lymphatic System Pharynx Digestive and Respiratory Systems

Answers to Workbook page 119 6. 7. Mouth, pharynx, esophagus, small intestine, blood, extracellular liquid, cell 8 a) it’s better to drink 3.25% whole milk (skim milk or 1% milk) b) We should eat at least two servings of fish every month . (week) c) It is better to eat whole fruits and vegetables than juices .  d) You should always  salt your food . (seldom) e) food prepared with fats should be avoided  f) we should eat at least one green and one orange vegetable every day  Although not required, I have shown why some answers are incorrect. Substance Input System responsible for its introduction Output System responsible for its elimination Amino Acids  Digestive Oxygen Respiratory Carbon dioxide Urine Urinary Glucose

Answers to Workbook page 119 9. The function of oxygen is to produce energy by oxidizing nutrients from our food in the mitochondria of our cells. (The exact wording may vary, but it should have something to do with getting energy.) 10. Our body needs energy during physical exercise. When our cells produce energy they also release carbon dioxide. The concentration of this gas increases in our body. Be must therefore increase our respiratory rhythm to expel it.

Answers to Workbook page 120 11 a. The blue arrow represents the air passage b. The red arrow represents food passage. c. d. #2 (the pharynx) e. the epiglottis (#4) closes the trachea when we swallow. 12 a. The esophagus is behind the trachea b. The trachea has cartilaginous rings c. The trachea must be kept open so that we can breathe. Number Structure number 1 Nasal passages 4 Epiglottis 2 Pharynx 5 Esophagus 3 Larynx