EXPLORING LIFE EXERCISE 13: THE RESPIRATORY, CIRCULATORY AND DIGESTIVE SYSTEMS OF THE RAT

EXPLORING LIFE EXERCISE 13: THE RESPIRATORY, CIRCULATORY AND DIGESTIVE SYSTEMS OF THE RAT

Exercise 13: Respiratory, Circulatory and Digestive Systems of the Rat Workbook Contents Corresponding Section on CD Vocabulary Key Concepts Introduction The Respiratory System Mechanics of Breathing Airways and Gas Exchange The Circulatory System The Heart Divided Circulation and Blood Pressure Cardiac and Vascular Muscle Arteries Veins The Digestive System Abdominal Cavity Liver and Pancreas The Stomach The Intestines 1. Introduction 2. The Respiratory System 2A. Mechanics of Breathing 2B. Airways and Gas Exchange 3. The Circulatory System 3A. The Heart 3B. Divided Circulation 3C. Blood Pressure 3D. Cardiac and Vascular Muscle 3E. Arteries 3F. Veins 4. The Digestive System 4A. Abdominal Cavity 4B. Liver and Pancreas 4C. Stomach 4D. Intestines Summary & Review Vocabulary Abdominal cavity - The part of the coelom or body cavity located below the diaphragm Alveolus - An individual air capsule within the lung Aorta - The major vessel of the arterial portion of the systemic circulation, emerging from the left ventricle of the heart Artery - A major blood vessel carrying blood away from the heart Atrium - Either of two superior chambers of the heart that receive venous blood Bile - A secretion of the liver that aids in the digestion of fats and the neutralization of stomach acid in the small intestine Bronchiole - A small division of a bronchus within the lung Bronchus - A branch of the trachea that leads to a lung Capillary - A microscopic blood vessel, connecting an arteriole and a venule, that is the primary site of exchange between the blood and the tissues Cardiac - Pertaining to the heart Cecum - The pouchlike portion of the large intestine to which the ileum of the small intestine is attached Coelom - The body cavity containing visceral organs Colon - The large intestine 13-1

Diaphragm - A dome of muscle and connective tissue that separates the thoracic and abdominal cavities Diastole - The sequence of the cardiac cycle during which the ventricles are relaxed and arterial blood pressure is lowest Duodenum - The first portion of the small intestine Esophagus - A tubular organ of the digestive system that leads from the pharynx to the stomach Gastric - Pertaining to the stomach Heart - A muscular pumping organ located in the thoracic cavity Hepatic - Pertaining to the liver Ileum - The terminal portion of the small intestine located between the jejunum and cecum Jejunum - The middle portion of the small intestine located between the duodenum and ileum Liver - Organ in the abdominal cavity that produces bile, stores carbohydrates and removes foreign chemicals from the blood Pancreas - Organ in the abdominal cavity that secretes digestive juices into the small intestine and insulin and glucagon into the blood Peritoneum - An epithelial and connective tissue membrane that lines the abdominal cavity and covers the abdominal viscera Portal system - A series of two capillary beds connected by a vein Pulmonary - Pertaining to the lungs Pulmonary circulation - The part of the circulatory system that carries deoxygenated blood from the heart to the lungs and returns oxygenated blood to the heart Rectum - The terminal portion of the digestive tract leading to the anus Small intestine - The portion of the digestive tract between the stomach and the cecum Stomach - A pouchlike digestive organ between the esophagus and the duodenum Systemic circulation - The part of the circulatory system that carries oxygenated blood from the heart to the tissues of the body and returns deoxygenated blood to the heart Systole - The phase of the cardiac cycle during which the ventricles are contracted and arterial blood pressure is highest Thoracic cavity - The part of the coelom or body cavity located above the diaphragm Trachea - The airway, commonly called the windpipe, which leads from the larynx to the bronchi Vein - A major blood vessel that conveys blood toward the heart Vena cava - The major vessel of the venous portion of the systemic circulation, connecting to the right atrium of the heart Ventricle - Either of two lower chambers of the heart that receive blood from the atria and pump the blood out of the heart into the circulation Villus - One of the projections of the intestinal wall Viscera - The organs within the abdominal and thoracic cavities 13-2

KEY CONCEPTS This section of the workbook is set up to help you note important information relating to the key concepts of this exercise and then organize and summarize the information in order to develop a synthesis and prepare for a review. As you complete this exercise, you will focus on the structures and their functions in the respiratory, circulatory and digestive systems: How are these systems structured? 1. What are the organs of each system? Where are they located? 2. What is important about the structure of some of these organs? 3. What are the cellular characteristics of some of these organs? How do these systems function? 4. What is the function of each organ in each system? 5. What is the order of the functions in each system? The first eight pages are questions that can be answered by following the progression of slides and paying careful attention to the information, both visual and audio. These questions should be read in advance of each section so that you can be better prepared to answer them by knowing what you are looking for. The underlined subheadings correspond to the sections of the exercise as outlined in the main menu. The subsequent three pages are designed to help you summarize and synthesize the pertinent information to answer the questions posed above. These are followed by a review quiz, which is also available on-screen as part of the exercise module. 13-3

RESPIRATORY, CIRCULATORY AND DIGESTIVE SYSTEMS Introduction 1. These three systems enable animals to obtain from. 2. The body cavity is called the coelom / viscera and the internal organs are the coelom / viscera. The coelom is divided into the abdominal / thoracic cavity above and the abdominal / thoracic cavity below. The two cavities are separated by the diaphragm / mesentery, a muscular sheet. The Respiratory System Mechanics of Breathing 3. Label each phrase (A) or (B) as illustrated by the appropriate diagram: Diagram A breathe in breathe out diaphragm up, reducing volume in thoracic cavity diaphragm down, creating a slight vacuum lungs contract and expel air lungs expand and take in air Diagram B 4. What happens to the lungs when the diaphragm is punctured? Airways and Gas Exchange 5. Connect these terms to the appropriate structures on the diagram: trachea bronchus bronchioles alveoli left lung lobe right lung lobe 6. Why do lungs have this complicated branching structure? 13-4

KEY CONCEPTS The Circulatory System The Heart 7. Connect these terms to the structures of the heart (you will have to view several sections to complete this): aorta right atrium right ventricle atrioventricular valves vena cava pulmonary artery pulmonary vein left atrium left ventricle semilunar valves 8. Match each part of the contraction cycle and each description with a step (1 through 5) from the diagram: Step 1 Step 2 Step 3 Step 4 Step 5 Contraction Cycle: atrial isometric isometric mid- ventricular contraction ventricular contraction ventricular relaxation diastole ejection Descriptions: ventricles contract; atrioventricular valves close semilunar valves close; atrioventricular valves reopen blood enters from venous system atria contract, forcing blood into ventricles ventricles contract, forcing blood through semilunar valves into arterial system 13-5

RESPIRATORY, CIRCULATORY AND DIGESTIVE SYSTEMS The Circulatory System Divided Circulation and Blood Pressure Note: The following questions will require the viewing and review of several consecutive movie sections 9. Connect these terms to the diagram, label the circulation systems and draw arrows that indicate the direction of blood flow. circulation pulmonary artery pulmonary veins aorta vena cavae arteries arterioles capillaries venules veins circulation 10. True or False (circle one): The right ventricle is more highly oxygenated than the left ventricle. True or False (circle one): Systemic circulation is less oxygenated than pulmonary circulation. 11. Label each part of the system with the appropriate blood pressure readings. True or False (circle one): Blood pressure in systemic circulation is higher than that in pulmonary. True or False (circle one): Blood pressure is higher in veins than in arteries. 12. Label the aorta in the heart diagrams (previous page, Question #8) with blood pressure readings. During which phase (step) is systolic blood pressure read? diastolic? Which reading is higher, diastolic or systolic? (circle one) Thought question: Which side of the heart has thicker, more muscular walls the right or the left? Why? 13. On which side of this micrograph is the artery? the vein? Why does one have a thicker wall than the other? 13-6

KEY CONCEPTS The Circulatory System Cardiac and Vascular Muscle 14. Label the following micrographs cardiac, skeletal, or smooth: 1) 2) 3) Which micrograph represents the wall of a blood vessel? muscle cells in the heart? 15. After each characteristic, write C (cardiac), Sk (skeletal) and/or Sm (smooth) where appropriate: has striations does not have striations has actin and myosin stacked does not have actin and myosin stacked has small, mononuclear cells has larger, multinuclear cells is myogenic is not myogenic What does myogenic mean? 13-7

RESPIRATORY, CIRCULATORY AND DIGESTIVE SYSTEMS Arteries 16. Match each artery to the diagram and to the organ(s)/tissue(s) (if any) to which it delivers blood: coronary arteries common carotid arteries subclavian arteries axillary arteries external carotid artery internal carotid artery inominate artery aorta celiac artery hepatic artery gastric artery splenic artery superior mesenteric artery renal artery genital arteries iliolumbar arteries inferior mesenteric artery caudal artery iliac arteries femoral arteries armpits, right and left side dorsal muscles of back face inner areas of the head inner thighs intestinal mesenteries only kidneys liver neck, right and left side ovaries (in female) shoulder and arm small intestines and intestinal mesenteries spleen stomach tail testes (in male) 13-8

KEY CONCEPTS Veins 17. Now match each vein with the diagram and the organ(s)/tissue(s) (if any) it conducts blood from: cranial vena cava external jugular vein axillary veins caudal vena cava hepatic vein renal veins genital veins iliac and femoral veins caudal vein gonads head kidneys legs liver lower body shoulders and arms tail upper part of body 18. Label the diagram with the following: direction of blood flow, artery, capillaries, portal vein, vein. What is this system called? What does it do? 19. Now label this system with these terms: gastric veins, mesenteric veins, splenic veins, hepatic portal vein. What is this system called? What is the importance of this system? 13-9

RESPIRATORY, CIRCULATORY AND DIGESTIVE SYSTEMS The Digestive System Abdominal Cavity Note: The following questions will require the viewing and review of several consecutive movie sections 20. Draw and label the four parts of the peritoneum: 21. Match each organ in the digestive system to its role(s) in digestion and secretion(s) (if any): Organ Role in Digestive System Secretions teeth (mouth) enzymatic digestion carbohydrates & fats amylase salivary glands (mouth) enzymatic digestion & initial absorption bacterial enzymes liver enzymatic digestion & final absorption bile pancreas enzymatic & mechanical digestion - proteins gastric acid esophagus indirect enzymatic digestion fats only insulin stomach indirect enzymatic digestion proteins, starch & fat lipase small intestines mechanical digestion only mucus large intestines peristalsis only; conduct food to stomach pancreatic juice rectum store and evacuate feces pepsin Liver and Pancreas 22. What are the other two roles of the liver? What is the role of insulin? The Stomach 23. Draw and label the parts of the stomach: cardiac sphincter, greater & lesser curvatures, pyloric sphincter. What is the role of the sphincters? 24. Beside activating pepsin to digest protein, what else does stomach acid do? Thought question: What protects the stomach from digesting itself? 13-10

KEY CONCEPTS The Stomach (continued) 25. Label this cross-section of the gastric mucosa: gastric glands gastric pits mucous cells submucosa parietal cells chief cells Parietal cells secrete pepsinogen / stomach acid while chief cells secrete pepsinogen / stomach acid. The Intestines 26. What are the three sections of the small intestines, in order? 27. To what digestive glands is the small intestines connected? 28. Label these cross-sections of the small intestines: villi microvilli epithelial cells lumen cell membrane tight junction intestinal gland capillary vein artery The villi increase absorption of nutrients by increasing surface area / mix intestinal juices while the microvilli increase absorption of nutrients by increasing surface area / mix intestinal juices. Where does the blood with the newly digested nutrient go first? Why? 29. Number the sections of the colon in order: ascending cecum descending rectum transverse What organisms live in the colon that aid digestion? 13-11

Number these statements in the appropriate sequence for each process: SUMMARY AND REVIEW Mechanics of Breathing diaphragm goes down diaphragm moves up lungs contract and expel air lungs expand and take in air thoracic cavity volume increases thoracic cavity volume decreases you breathe in you breathe out Contraction Cycle atria contract, forcing blood into the ventricles blood enters atria from venous system semilunar valves close and atrioventricular valves reopen ventricles contract ventricles relax Divided Circulation blood enters left atrium from pulmonary circulation blood enters right atrium from systemic circulation blood exits left ventricle and enters systemic circulation blood exits right ventricle and enters pulmonary circulation carbon dioxide is removed from blood and blood is oxygenated in lungs oxygen is removed from and waste products are added to blood at cells/capillaries Digestion esophagus delivers food to stomach via peristalsis food is chewed and salivary secretions begin starch and fat digestion large intestines complete digestion and absorption rectum evacuates feces small intestines continue chemical digestion and begins absorption stomach continues mechanical digestion and begins protein digestion 13-12

RESPIRATORY, CIRCULATORY AND DIGESTIVE SYSTEMS Match the organ/secretion with its description AND function by placing the appropriate number AND letter in the column provided. Then label the system in which the organ/secretion is found as follows: C = circulatory, D = digestive, R = respiratory. The first one has been done for you. Number Letter Number + Letter Organ/Secretion Description/Function 1 alveoli A activate pepsin and kill microorganisms 1 G R 2 amylase B aid digestion in large intestines 3 aorta C begin fat digestion 4 arteries D begin mechanical digestion 5 arterioles E begin starch digestion 6 atrioventricular valves F branching structures that connect the trachea to alveoli 7 bacterial enzymes G capillary-covered sacs that increase surface area for gas exchange 8 bile H cartilagenous structure that connects nasal and oral cavities to lungs 9 bronchi/bronchioles I conduct blood from aorta to arterioles 10 capillaries J conduct blood from arteries to capillaries 11 cardiac sphincter K conduct blood from capillaries to veins 12 chief cells L conduct blood from venules to vena cava 13 diaphragm M conduct oxygenated blood to tissues, deoxygenated blood away 14 esophagus N continue chemical digestion and begin absorption of nutrients 15 gastric acid O continue mechanical and chemical digestion 16 insulin P deliver deoxygenated blood from body tissues to right atrium 17 large intestines/colon Q deliver deoxygenated blood from right ventricle to lungs 18 left atrium R deliver food from mouth to stomach through peristalsis 19 left ventricle S deliver oxygenated blood from left ventricle to body tissues 20 lipase T deliver oxygenated blood from lungs to left atrium 21 liver U digest fats in small intestines 22 lungs V digest fats, starches and proteins in small intestines 23 microvilli W digest protein 24 mucus X expand and contract with downward and upward movement of diaphragm 25 pancreas Y finish chemical digestion and absorption of nutrients, secrete mucus 26 pancreatic juice Z increase absorptive surface area and mix intestinal juice 27 parietal cells AA increase absorptive surface area of small intestines 28 pepsin BB lubricate passage of feces 29 pulmonary artery CC muscular sheet; divides abdominal from thoracic cavity; aids in breathing 30 pulmonary veins DD prevent backflow from blood vessels into ventricles 31 pyloric sphincter EE prevent backflow from ventricles into atria during ventricular contraction 32 rectum FF prevent backflow of digested materials into esophagus 33 right atrium GG prevent backflow of digested materials into stomach 34 right ventricle HH produce amylase and lipase 35 salivary glands II produce bile, store glycogen and metabolize nutrients and toxins 36 semilunar valves JJ produce gastric acid 37 small intestines KK produce pancreatic juice and insulin 38 stomach LL produce pepsinogen, which is converted to pepsin by stomach acid 39 teeth MM receives blood from left atrium and pumps into systemic circulation 40 trachea NN receives blood from pulmonary circulation and pumps into left ventricle 41 veins OO receives blood from right atrium and pumps into pulmonary circulation 42 vena cava PP receives blood from systemic circulation and pumps into right ventricle 43 venules QQ regulate glucose metabolism 44 villi RR store and evacuate feces System 13-13

SUMMARY AND REVIEW Label the major organs and blood vessels on the diagram below: 13-14