Tenth Biology Transportation - The Circulatory System I. Conceptual understanding 1. Write the differences between arteries, veins and capillaries. (4 Marks) A: (Prepare such tables wherever necessary in any lesson. You can prepare such tables for the valves of heart, cardiac cycle, xylem and phloem etc., add relevant columns and row when you prepare such tables and it would be an added advantage if you can add the diagrams as given in the table.) Blood Figure Thickness Function Lumen Capacity to No.of layers vessel of the size retain shape Thick, Artery Thick Transports blood Narrow Elastic Two thick elastic away from the heart. (they can muscular Small lumen Transports only stretch and layers oxygenated blood. recoil) Vein Thin Thin Supplies components Wide Less elastic Three layers Large lumen valve to tissues. Removes wastes. Exchanges oxygen, carbon dioxide, water, salts between blood and surrounding body tissue. Capillaries Single cell Transports blood Very Not One Single cell very towards the heart. narrow elastic cell thick thin Transports deoxygenated blood. R-12-1-15
II. Asking questions and making hypothesis 1. What questions would you ask a doctor about the Sphygmomanometer? (2 Marks) A: If I visit a doctor, I would ask the following questions about Sphygmomanometer. 1. What is the name of this instrument? 2. Why are you wrapping the cloth/cuff tightly on the upper arm of the patient? 3. What is the normal blood pressure of a human being? 4. Why is the pump used? 5. Why is the dial used? 6. What is the use of the valve? 7. How is stethoscope useful in determining the systole and diastole? (Practice preparing different types of questions in relation to each concept discussed in the lesson. The questions should be thought provoking.) III. Experimentation and Field Investigation 1. Anand observed a mammalian heart while his teacher demonstrated the experiment. He noted the observations in his lab record. Did you observe a mammalian heart in your classroom activity or by going out to observe in a butcher's shop? What was your experience? Explain. (4 Marks) A: Yes. I went to a butcher's shop to observe a mammalian heart. I observed a sheep's heart. I brought it to school and asked our teacher to explain. She has demonstrated an experiment. I am writing my observations below. Aim: Observation of the internal structure of the mammalian heart. Material required: Since the structure of all the mammalian hearts is similar, we take the sheep's or goat's for our observation. For this we need the following materials. Freshly collected specimen of heart of sheep / goat from the butcher. Soda straws, Sharp and long blade / scalpel, Tray and a jug of water. Dissection scissors and forceps. Procedure: We washed the heart thoroughly so that blood is completely drained from the chambers.
We took the soda straws and inserted them into the stumps of the blood vessels. We observed the arrangement of blood vessels on the of the heart. We placed the heart in the tray in such a way that a large arch like tube faces upwards. We observed it to be the ventral side. Then we took a sharp blade/scalpel and opened the heart in such a way that the chambers are exposed. Observations: We observed the thickness of the of the heart, number of chambers, size of the chambers and the differences between the chambers, connection of chambers with each other. We observed white coloured structures in the lower part of the heart, noted down the size and shape and to which parts they are attached. Inference: The heart is covered by two layers of membranes. The heart is divided into four parts by grooves. Two upper parts are called Atria, and the lower ones are called Ventricles. The two atria and the two ventricles are separated from each other by muscular partitions called septa. The openings between atria and ventricles are guarded by valves. After careful examination we can observe valves in the pulmonary artery and aorta as well. Right ventricle Left atruim Chordae tendinae Left atrioventricular valve Left ventricle
IV. Information Skills and Projects 1. Aravind went to a zoology lecturer and collected information about mode of circulation in different Phyla. He recorded the information he collected, in his project work book. Can you write your data about the same topic in a tabular form? (4 Marks) A: I went to a zoology lecturer and collected information about mode of circulation in different Phyla. She explained me everything and have shown me images of different examples from each Phyla. Here is my project work. Name of Example Diagram Mode of Circulation the Phylum Protozoans Unicellular organisms Parazones (sponges) Cnidarians Brownian movement of protoplasm Use sea water and transport materials with the help of flagella. Have a blind sac like gastro vascular cavity to transport materials. Platyhelm enths Nemathelme nthes Annelids Arthropods Echinoderms Molluscs Amoeba Sponge Hydra and jelly fish Fasciola hepatica Round worm Molluscs and lower chordates too Cephalopod mollusks and higher animals Blue ringed octopus, snail O 2 CO 2 Food Vacuole Have branched digestive and excretory systems. Consist of pseudocoelom that collect and distribute materials. (First Eucoelomate animals) have pulsatile vessel for transportation. Consist of pulsatile organ called heart to pump the blood. It directly supplies nutrients and oxygen to the tissues through flooding of blood (open type of circulatory system). Blood flows in blood vessels (closed type of circulatory system). Molluscs' circulatory systems are mainly open. Although molluscs are coelomates, their coeloms are reduced to fairly small spaces enclosing the heart and gonads. The main body cavity is a hemocoel through which blood and coelomic fluid circulate and which encloses most of the other internal organs.
V. Communication through drawing, model making 1. Draw the internal structure of human heart and label its parts. (5 Marks) A: Answer the following questions: (a) What is it that protects the heart? (b) What is the study of human heart and its disorders called as? (c) Expand ECG. Anterior vena cava artery Right ouricle Arteries to head Artery to left arm Aorta Tricuspid valve Posterior vena cava Right ventricle Internal structure of heart a) Rib cage b) Cardiology c) Electro Cardio Gram. VI. Appreciation and aesthetic sense, values 1. How would you appreciate the Lymphatic system? (2 Marks) A: Lymphatic system is the system that transports the tissue fluid into the main blood stream. It is the vital link between blood and tissues by which essential substances pass from blood to cells and excretory products from cells to blood. It carries digested and absorbed fats from small intestine to different tissues of the body. It helps in removing waste materials from the cells in the body to drain into blood. It protects cells in the tissues from infection. Writer: K. Vijaya Bhanu artery veins Left auricle Semi-lunar valve Bicuspid valve Wall of left ventricle