Unit 9 –Human Systems: Digestive, Endocrine

Circulatory, Respiratory and Excretory Systems

MAIN IDEA: THE CIRCULATORY SYSTEM TRANSPORTS BLOOD TO DELIVER IMPORTANT SUBSTANCES, SUCH AS OXYGEN, TO CELLS AND TO REMOVE WASTES LIKE CARBON DIOXIDE

OBJECTIVE 1: Identify the main functions of the circulatory system

A. The body’s transport system is the circulatory system, consisting of blood, the heart, blood vessels and the lymphatic system. They work together to maintain homeostasis.

B. The circulatory transports many important substances like oxygen and nutrients.

C. The circulatory system allows cells to get rid of waste.

D. The blood carries disease fighting materials produced by the immune system

E. The blood has cell fragments and proteins for clotting blood.

F. The circulatory system distributes heat throughout the body to help regulate body temperature.

OBJECTIVE 2: DISTINGUISH AMONG THE DIFFERENT TYPES OF BLOOD VESSELS OF THE CIRCULATORY SYSTEM

  1. Review heart diagram. Know structures and functions.
  2. There are three main types of blood vessels to channel blood throughout your body. (see page 993).
  1. Arteries:
  1. carry blood away from the heart, small arteries are called arterioles
  2. walls are thick and elastic to withstand high pressure as blood is pumped from the heart.
  3. “hardening of the arteries is called artheroscelrosis: deposits of fatty materials/cholesterol, heart has to work harder and blood pressure increases, which can lead to heart attacks and strokes. Heart attacks occur when blood does not reach the heart muscle. Strokes occur when clots form in blood vessels supplying oxygen to the brain. This can lead to ruptured blood vessels and internal bleeding.

2. Capillaries

  1. microscopic connections between arterioles and venules
  2. one cell thick, exchange of materials takes place here (O2/CO2, nutrients, wastes)

3. Veins:

  1. move blood toward the heart; small veins are called venules
  2. walls are thin; valves allow the blood to move in one direction only
  3. varicose veins: broken valves, blood pools, walls stretch out.

OBJECTIVE 3: DESCRIBE THE STRUCTURE OF THE HEART, HOW THE HEART BEATS AND THE FLOW OF BLOOD IN THE BODY

A. Your heart is a little larger than your fist and it functions to keep the blood moving constantly throughout the body. It pumps oxygenated blood to your body and deoxygenated blood to your lungs.

  1. Made of cardiac muscle high in mitochondria capable of conducting electrical impulses for muscular contractions.
  2. Consists of four chambers; two atria and two ventricles
  1. atria: collect blood from the body (right) or lungs (left); thin
  2. ventricles: pump blood to the body (left) or to the lungs (right); thick and muscular
  3. valves are between the atria/ventricles and ventricles/vessels

B. Heartbeat cycle:

  1. The heart acts in two main phases
  1. Phase one – atria fill with blood, then contract to fill the ventricles
  2. Second phase – ventricles contract to pump blood out of the heart to the lungs and forward into the body.
  1. heartbeat: valves shutting, AV and then semilunar
  1. Control of heart rate:
  1. cardiac muscle has a built-in ability to contract, your brain, the medulla oblongata, only tells it to speed up or slow down the rate of contractions.
  2. The heart rate is set by the S/A node or pacemaker, a bundle of nerve cells located at the top of the right atrium. Sends electrical impulses that spread over both atria and both ventricles.
  1. A pulseis a surge of blood through an artery. Every time the heart beats a surge of blood flows from the left ventricle into the aorta and then into the arteries.
  1. blood pressure is the force that the blood exerts as it pushes against the walls of an artery.
  2. Blood pressure rises and falls as the heart contracts(systole) and then relaxes (diastole).

3. Blood pressure can be increased by exercise, stress, and alcohol. An average adult blood pressure is 120 (systolic pressure)/80 (diastlolic pressure)

  1. Blood circulates around the heart and lungs (pulmonary) and the heart and body tissues (systemic)
  1. Pulmonary Circulation:
  1. rv--. pulmonary arteries arteries arterioles capillaries around alveoli to drop of CO2 and pick up O2 venules veins pulmonary veins la
  1. Systemic Circulation:
  1. lvaorta ateries arterioles capillaries around the body tissues to drop of O2 and pick up CO2 venules veins superio/inferior vena cavas ra
  1. There are three important areas concerning ciculation:
  1. coronary circulation: around the heart muscle
  2. Hepatic-portal circulation: between the small intestine and liver for nutrient regulation
  3. Renal circulation: kidneys

D. The digestive and respiratory systems depend on the circulatroy system to transport nutrients and oxygen to the cells and wastes and carbon dioxide away from the cells. The systems are interdependent on one another.

OBJECTIVE 4: DISTINGUISH AMONG THE VARIOUS COMPONENTS OF BLOOD AND BLOOD GROUPS

  1. Human blood is a tissue composed of fluid, red and white blood cells, and cell fragments.
  1. Plasma – the fluid portion of blood that contains proteins; transports red and white blood cells, platelets, nutrients, enzymes, hormones, gases, and inoranic salts. Makes up about 50% of the total volume of blood.
  2. Red Blood Cells (RBC’s) – Transport oxygen and some carbon dioxide, lack a nucleus; contain hemoglobin.
  1. Remain active for about 120 days then they break down in the spleen and liver and are removed as waste
  2. Hemoglobin is an iron-containing protein to which oxygen lossely binds.
  1. White Blood Cells (WBC’s) – Large, several different types, all contain a nucleus, defend the body against disease by attacking bacteria and other microorganisms; produce antibodies, Survive for months or years.
  2. Platelets – cell fragments needed for clotting. Produced in the bone marrow, survive for about one week, produce a sticky network of protein fibers called fibrin over the wound
  1. There are four human blood groups – A, B, AB, and O (see page 998)
  1. Differences in blood groups are due toi the presence or absence of proteins, called antigens on the membranes of RBC’s. Antigens can stimulate an immune response. The letters A and B stand for the types of blood surface antigens.
  2. Blood plasma contains antibodies, proteins that are shaped to to correspond with the different types of antigens.When antigens react to antibodies, it causes your blood to clot clump. Clumped blood cannot transport oxygen.
  3. Transfusions require that antibodies will not react with antigens.

Blood Types / Antigens / Antibodies / Can accept: / Can donate to:
A / A / B / A, O / A, AB
B / B / A / B,O / B, AB
AB / AB / None / A, B, AB, O / AB
O / none / A and B / O / A, B, AB, O
  1. Another characteristic of RBC’s in the presence or absence of an antigen called Rh, or Rhesus factor
  1. (Rh+) - have the Rh antigen, (Rh-) – the Rh antigen is missing
  2. Can cause complication in some pregnancies if Rh- mom becomes pregnant with an Rh+ baby.
  1. At birth Rh+ baby’s blood mixes with mom’ Rh- blood.
  2. Mom will make anti-Rh+ antibodies
  3. During a second pregnancy these antibodies cross the placenta
  4. If the new fetus is Rh+, the anti-Rh+ antibodies from the mom will destroy the RBC’s of the fetus.
  1. Treatment is available. Rh- mother is given a substance that removes the Rh antibodies from her blood so that the next fetus will not be in danger.

MAIN IDEA: THE FUNCTION OF THE RESPIRATORY SYSTEM IS THE EXCHANGE OF OXYGEN AND CARBON DIOXIDE BETWEEN THE ATMOSPHERE AND THE BLOOD AND BETWEEN THE BLOOD AND THE BODY’S CELLS.

OBJECTIVE 5: DEFINE RESPIRATION, LIST THE COMPONENTS OF THE RESPIRATORY SYSTEM,

AND DESCRIBE THE RESPIRATORY SURFACE

  1. Respiration includes all the mechanisms involved in getting oxygen to the cells of your body, getting rid of carbon dioxide and the formation of ATP within the cells.
  2. Your respiration system is composed of a pair of lungs, a series of passageways into your body, and a thin skeletal muscle called the diaphragm.
  3. A respiratory surface must be:
  1. thin: to allow diffusion
  2. moist: so gases can be dissolved and diffuse
  3. near a transport system

OBJECTIVE 6: DISTINGUISH BETWEEN BREATHING AND RESPIRATION

  1. Breathing – the movement of air into and out of the lungs
  2. External respiration – the exchange of oxygen and carbon dioxide between the air and the blood in the lungs
  3. Circulation – the carrying of dissolved gases by the blood to and from the body cells
  4. Internal respiration – the exchange of oxygen and carbon dioxide between the blood and the body cells

OBJECTIVE 7: DESCRIBE THE PATH AIR TAKES INCLUDING THE IMPORTANCE OF THE ALVEOLI, THE TRANSPORT OF GASES AND HOW DIRTY AIR IS CLEANED

A. Know the structures and functions on your diagram

B. Air is taken into the body through the nose and mouth flows into the pharynxpasses the epiglottis through the larynx (voicebox) down the trachea into two bronchi tubes branch further into bronchial and finally bronchiole tubes branch into millions of thin-walled sacs called alveoli.

  1. Our respiratory surface is made of alveoli which are covered by capillaries.
  2. Oxygen and carbon dioxide are exchanged by diffusion here. Occurs easily as wallls of alveoli and capillaries are only one cell thick.

C. Once oxygen from the air diffuses into the blood vessels surrounding the alveoli, it is pumped by the heart to the body cells where it is used for cellular respiration.

  1. Waste products of cellular respiration (carbon dioxide) diffuses into the blood, which carries it back to the lungs, where it diffuses from the blood into the alveoli. It is removed during exhalation.
  2. At the same time, oxygen from the air diffuses back into the lungs and alveoli making the blood once again oxygen rich.

D. The air we breath is not clean and can contain 20 million particles of foreign matter a day.

  1. The nasal cavity, trachea, and bronchi are lined with ciliated cells that secrete mucus to preventmost of this material from reaching your lungs.
  1. Cilia constantly beat upward in the direction of your throat, where foreign material can be swallowed or expelled by coughing or sneezing.

OBJECTIVE 8: DESCRIBE THE MECHANICS OF BREATHING AND THE CONTROL OF RESPIRATION

  1. The action of your diaphragm and the muscles between your ribs enable you to breathe in and out.
  2. Inhalation:
  1. Muscles between your ribs contract raising the rib cage
  2. Diaphragm contracts, becomes flattened and moves lower into your chest cavity
  3. Increased space in the chest cavity creates a slight vacum and air rushes in
  1. Exhalation:
  1. Muscles of the ribs and your diaphragm relax and ribs drop down in the chest cavity.
  2. Volume of the chest cavity decreases and forces most of the air out. Some air remains in the alveoli.
  1. Breathing is usually an involuntary process, controlled by the chemistry of your blood as it interacts with a part of your brain called the medulla oblongata.
  1. Medulla oblongata maintains homeostasis.
  1. higher levels of xcarbon dioxide in the blood causes it to send nerve signals to the rib muscles and diaphragm. Nerve impulses cause these muscles to contract and you inhale.

OBJECTIVE 9: LIST THE HARMFUL ELEMENTS IN SMOKE AND THE RISKS SMOKING POSES TO YOUR RESPIRATORY AND CIRCULATORY SYSTEMS

  1. Smoke from cigarettes contains over 3000 harmful chemicals:
  1. Carbon monoxide: interfers with oxygen transport in RBC’s, affecting vision, hearing, and judgement
  2. Tars: carcinogenic
  3. Nicotine: CNS stimulant, addictive, and affects blood pressure, skin temperature, hormone production, and muscle tension
  1. Smoking Risks:
  1. Cancer: lungs (90% fatal), throat, mouth, esophagus, bladder
  2. Heart Disease: twice as likely to have a heart attack anf four more times likely to die within an hour of it.
  3. Respiratory Problems: colds, chronic bronchitis, and emphysema

MAIN IDEA: THE KIDNEYS MAINTAIN HOMEOSTASIS BY REMOVING WASTES AND EXCESS WATER FROM THE BODY AND BY MAINTAINING THE pH OF BLOOD.

OBJECTIVE 10: DESCRIBE THE STRUCTURES AND FUNCTIONS OF THE URINARY SYSTEM AND HOW THEY HELP TO MAINTAIN HOMEOSTASIS

  1. Know the structures and functions of your diagrams
  2. Excretion is the removal of cellular wastes: CO2, H2O, salts, and nitrogen compound to help regulate the chemical makeup of the blood and other body fluids
  1. Excretion can be carried out by the liver, skin glands, lungs, and the urinary system
  1. The urinary system is composed of two kidneys, a pair of ureters, the urinary bladder, and the urethra.
  2. The kidneys filter the blood to remove wastes from it, thus maintaining homeostasis.
  3. Structures and Functions within Urinary System:
  1. nephron: functional unit of the kidney; 1.25 million/kidney
  2. blood enters kidney through renal artery
  3. filtration: at the glomerulus (ball of capillaries) all substances ( that are small enough) pass from the blood into the Bowman’s capsule
  4. reabsorption of useful materials out of the Loop of Henle and into surrounding capillaries
  1. water by osmosis
  2. active transport of nutrients, amino acids, and salt ions
  3. maintains homeostasis
  1. excretion: whatever is not reabsorbed (urine) goes to the collecting duct pelvis ureter bladder urethra out
  1. Urine is excess water, waste molecules, and excess ions
  1. The urinary system helps maintain the homeostasis of body fluids:
  1. Removes urea and ammonia, both of which are toxic by products from the breakdown of proteins
  2. Controls the level of sodium in the blood by removing and reabsorbing sodium ions (controls osmotic pressure of the blood)
  3. Regulates the pH of the blood by filtering out hydrogen ions and allowing bicarbonate to be reabsorbed back into the blood.

OBJECTIVE 11: DISCUSS THE IMPORTANCE OF COORDINATION OF STRUCTURES AND FUNCTIONS OF ORGAN SYSTEMS

  1. The coordination of structures and functions of the organ systems allows the internal environment of the human body to remain relatively stable (homeostatic) despite changes to the outside environment.

1. The complementary activity of the major body systems provides cells with oxygen and nutrients and removes toxic products such as carbon dioxide and nitrogen compounds.

  1. See handout integration of systems
  2. All of these chemicals are transported by the circulatory system and the cells. Organs at the final destination direct the chemicals to their exit from the circulatory system.

OBJECTIVE 12: DESCRIBE SOME DISORDERS OF THE KIDNEYS AND THEIR POSSIBLE TREATMENTS

  1. Kidney function can be inhibited by infections or disorders. If impaired the body cannot rid itself of wastes and homeostasis might be disrupted.
  2. Infections – often begin as a bladder infection. Antibiotics are usually effective in treating infections
  3. Nephritis – inflammation and painful swelling of the glomeruli caused by the lodging of large particles from the bloodstream.
  4. Kidney stones – a crystallized solid, like calcium compounds, that form in the kidney. Small stones may be passed out in the urine (OUCH!) while larger stones are broken apart by ultrasonic soundwaves. Sometimes surgery is needed to remove the stones.
  5. Diabetes and high blood pressure are two of the most common reasons for reduced kidney function and kidney failure.

B.Modern treatment exists for reduced kidney function or complete kidney failure.

1. Dialysis – An artificial kidney machine filters out waste and toxins from a patients blood.

2. Kidney transplant – The surgical placement of a healthy kidney from another person into a patients body. A major complication of a transplant is the rejection of the donated organ. As a result, medication is needed to prevent rejection.

MAIN IDEA: THE DIGESTIVE SYSTEM BREAKS DOWN FOOD SO NUTRIENTS CAN BE ABSORBED BY THE BODY

OBJECTIVE 12: RECOGNIZE THE DIFFERENT FUNCTIONS OF THE DIGESTIVE TRACT AND DIFFERNTIATE BETWEEN CHEMICAL AND MECHANICAL DIGESTION

  1. The three functions of the digestive system is to ingest food, break it down so nutrients can be absorbed, and eliminate what cannot be digested.
  2. Digestion is accomplished through a number of steps:
  1. The system takes ingested food and begins moving it through the digestive tract.
  1. Mechanical digestion occurs when teeth or muscles physically break the food down into smaller pieces. Prepares food for chemical digestion.
  2. Chemical digestion occurs when enzymes are used to break the bonds between molecules so that nutrients can be absorbed.
  1. The system absorbs the digested food and distributes it to your cell via the circulatory system
  2. The system eliminates undigested materials from your body.

OBJECTIVE 14: KNOW THE ORGANS AND ENZYMES OF THE HUMAN DIGESTIVE SYSTEM AND BE ABLE TO EXPLAIN HOW EACH CONTRIBUTES TO DIGESTION

  1. Mouth:
  1. Mechanical digestion (teeth) of everything and chemical (salivary amylase) digestion of carbohydrates (starches) into sugars.
  2. Tongue pushes food to the back of the mouth, swallow, food in pharynx, and the epiglottis covers the trachea.
  1. Esophagus: a muscular tube that connects pharynx to the stomach.
  1. peristalsis – wave-like contractions push the food towards the stomach (see page 950)
  2. cardiac sphincter is the valve between the stomach and the esophagus.
  1. Stomach:
  1. Mechanical digestion (muscles ) of everything and chemical digestion of proteins
  1. pyloric glands – secret mucus to protect the stomach lining
  2. gastric glands – secrete HCl and the enzyme pepsin for the digestion of proteins. This is stimulated by thought, smell, sight, or taste of food or stretching of the walls of the stomach

3. Stomach acidity has a pH of about 2, a very strong acid. If the cardiac sphincter allows leakage into the esophagus, this causes heartburn.

4. Food will stay in your stomach for 2-4 hours. The end product is called chime.

5. Pyloric sphincter – the valve between the stomach and the small intestine

  1. Ulcers: not enough mucus or may be caused by a virus.

7. The stomach does absorb alcohol and aspirin.