8 Transport in humans

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The transport system includes the (1) ( 循環系統 ) and the (2) ( 淋巴系統 ).

1 Class: Name: ( ) Date: 8 Transport in humans 8.1 The human transport system (Book 1B, p. 8-3) In humans, a transport system is developed to ensure the supply of useful substances to all cells and removal of waste from them. The transport system includes the (1) ( 循環系統 ) and the (2) ( 淋巴系統 ). The functions of different parts of the human circulatory system: Part Function I Blood a Acts as a pump to drive blood throughout the body II Blood vessels ( 血管 ) b Carries useful substances and waste to and from III Heart body cells c Allow exchange of materials between blood and body cells d Distribute blood throughout the body I: (3) II: (4) & (5) III: (6) 8.2 Blood (Book 1B, p. 8-4) Blood is a tissue composed of blood cells suspended in (1) ( 血漿 ). 1 Plasma Plasma consists of 90% water and 10% dissolved substances including carbon dioxide, nutrients, urea, hormones and plasma proteins like (2) ( 抗體 ) and (3) ( 纖維蛋白原 ). It transports dissolved substances and distributes (4) throughout the body. Centrifuged blood plasma blood cells (Second Edition)

2 Blood cells The structures and functions of different blood cells: Red blood cells White blood cells Blood platelets Two major types: nuclei Very small pieces of cell fragments whole section

nucleus Site of In (8) In bone marrow and In bone marrow production ( 骨髓 ) (9) of bones like limb bones, ( 脾 ); mature in lymph ribs and vertebrae ( 椎骨 ) nodes ( 淋巴結 ) Site or method In the liver and

2 2 Blood cells The structures and functions of different blood cells: Red blood cells White blood cells Blood platelets Two major types: nuclei Very small pieces of cell fragments whole section phagocyte ( 吞噬細胞 ) lymphocyte ( 淋巴細胞 ) Shape (5) Irregular shape Irregular shape shape Colour Red due to the pigment Colourless Colourless (6) Nucleus No nucleus when mature Large round or (7) No nucleus Site of In (8) In bone marrow and In bone marrow production ( 骨髓 ) (9) of bones like limb bones, ( 脾 ); mature in lymph ribs and vertebrae ( 椎骨 ) nodes ( 淋巴結 ) Site or method In the liver and spleen; Some are killed by germs In the liver and spleen of destruction haemoglobin is broken or passed out of the body down into iron and in faeces (10) Function Contain haemoglobin to Protect our body against Involved in carry diseases by killing germs (12) (11) to prevent further blood loss and entry of germs into our body Go to Practical 8.1 Examination of a blood smear (Book 1B, p. 8-6; Practical Workbook for SBA 1B, p. 8-1) (Second Edition)

3 8.3 Blood vessels (Book 1B, p. 8-8) There are three types of blood vessels: (1) ( 動脈 ), (2) ( 靜脈 ) and (3) ( 微血管 ). Differences between arteries and veins: Artery Vein small lumen fibrous tissue thick layer of muscle and elastic tissue thick wall large lumen fibrous tissue thin layer of muscle and elastic tissue thin wall Cross section Cross section valve Longitudinal section Longitudinal section Direction of blood flow Away from the heart Towards the heart Location Usually deep inside the body Relatively close to the body surface Nature of blood carried Driving force for blood flow Blood pressure (4) (oxygenated / deoxygenated) blood (except in the pulmonary artery and the umbilical arteries) Provided by the pumping action of the (6) High, due to the pumping action of the heart (5) (oxygenated / deoxygenated) blood (except in the pulmonary veins and the umbilical vein) Provided by the contraction of the (7) that squeeze on the veins Low (the pressure drops after blood passing through the (8) ) Wall Thicker, with more elastic tissue Thinner, with less elastic tissue Lumen Smaller Larger (resistance to blood flow is reduced) Presence of valves Not present (except in the pulmonary artery and the aorta which have valves at their base) Valves are present to prevent the (9) of blood (Second Edition)

4 Capillaries connect the arterioles ( 小動脈 ) to the venules ( 小靜脈 ). They form (10) ( 微血管床 ) in the body tissue to allow exchange of materials between blood and body cells. Structure of a capillary: capillary wall: lumen: very small (11) thick; (12) permeable The change in blood pressure along different blood vessels: blood pressure (mmhg) artery arteriole capillary venule vein Blood vessel Arteries and arterioles Capillaries Veins and venules Blood pressure (13) due to the pumping action of the heart Changes (14) as the heart contracts and relaxes Drops significantly because the small diameter of the capillaries offers a high (15) to blood flow Much lower because the blood has overcome great resistance of the blood vessel walls after travelling a long distance Go to Practical 8.2 Examination of transverse sections of an artery and a vein (Book 1B, p. 8-10; Practical Workbook for SBA 1B, p. 8-4) Practical 8.3 Examination of the capillary flow in a fish tail fin (Book 1B, p. 8-12; Practical Workbook for SBA 1B, p. 8-7) (Second Edition)

5 8.4 The heart (Book 1B, p. 8-15) The heart is located between the two lungs and is protected by the rib cage. It is surrounded by a membrane called the (1) ( 圍心膜 ). A What is the structure of the heart? (Book 1B, p. 8-15) The heart is mainly made up of (2) ( 心肌 ). The (3) ( 冠狀動脈 ) supply oxygen and nutrients to the cardiac muscles. The (4) ( 冠狀靜脈 ) carry carbon dioxide and other waste away. Internal structure of the heart: anterior vena cava ( 前腔靜脈 ) (5) ( 半月瓣 ) (7) ( 大動脈 ) pulmonary artery pulmonary veins left atrium ( 左心房 ) (8) right atrium ( 右心房 ) (6) ( 三尖瓣 ) right ventricle ( 右心室 ) ( 二尖瓣 ) heart tendon ( 心腱索 ) left ventricle ( 左心室 ) (9) ( 隔 ) posterior vena cava ( 後腔靜脈 ) Structure Atria Feature and function Smaller, upper chambers of the heart (10) (Thinner / Thicker) muscular wall than the ventricles The right atrium receives (11) (oxygenated / deoxygenated) blood from the (12) and pushes it to the right ventricle The left atrium receives (13) (oxygenated / deoxygenated) blood from the (14) and pushes it to the left ventricle (Second Edition)

6 Ventricles Septum Larger, lower chambers of the heart (15) (Thinner / Thicker) muscular wall than the atria The (16) ventricle has a thicker wall because it has to provide greater force to pump blood to all parts of the body (except the lungs) The right ventricle pumps (17) (oxygenated / deoxygenated) blood to the lungs via the (18) The left ventricle pumps (19) (oxygenated / deoxygenated) blood to the rest of the body via the (20) Separates the two sides of the heart to prevent the mixing of oxygenated and deoxygenated blood The bicuspid and tricuspid valves prevent the backflow of blood into the (21) Semilunar valves prevent the backflow of blood into the (22) Heart valves tricuspid valve bicuspid valve aorta pulmonary artery semilunar valves Cross section of the heart showing the heart valves (viewed from the top) B What are the adaptive features of the heart for pumping blood? (Book 1B, p. 8-19) The cardiac muscles can contract and relax continuously without fatigue. The (23) have a thick muscular wall that provides a strong force of contraction to drive blood over a long distance to all parts of the body. The bicuspid valve, tricuspid valves and semilunar valves prevent the backflow of blood. (24) prevent the bicuspid and tricuspid valves from turning inside out. (Second Edition)

7 Go to Practical 8.4 Dissection and examination of a pig heart (Book 1B, p. 8-18; Practical Workbook for SBA 1B, p. 8-10) 8.5 Blood circulation (Book 1B, p. 8-21) When blood flows throughout our body in one complete loop, it passes through the heart (1) (once / twice). This type of circulation is called a (2) ( 雙循環 ). pulmonary artery lungs pulmonary circulation pulmonary veins venae cavae right atrium right ventricle left atrium left ventricle aorta systemic circulation all other parts of the body Key: oxygenated blood deoxygenated blood Double circulation in humans Pathway Pulmonary circulation Right atrium right ventricle pulmonary artery (3) pulmonary veins left atrium Systemic circulation Left atrium left ventricle (4) all parts of the body except the lungs venae cavae right atrium Change of blood Becomes (5) Becomes (6) (Second Edition)

8 Most organs receive blood from an artery head, neck, arms and drain blood into a vein, but the liver receives blood from two blood vessels: the hepatic artery and the lungs (7) ( 肝門靜脈 ). The hepatic portal vein links the (8) to the liver. liver heart small intestine hepatic artery hepatic portal vein kidneys legs The human circulatory system 8.6 Exchange of materials between blood and body cells (Book 1B, p. 8-25) A How are materials exchanged between blood and body cells? (Book 1B, p. 8-25) All body cells are bathed in (1) ( 組織液 ). At the (2), useful materials in the blood diffuse into the tissue fluid and then into the body cells. Waste products from body cells diffuse in the opposite direction. Adaptation of capillaries for exchange of materials: Feature One-cell thick walls Numerous branches Large total cross-sectional area Adaptation Provides a (3) distance for diffusion Provide a large (4) for diffusion (5) blood flow allows more time for exchange of materials (Second Edition)

9 B How is tissue fluid formed? (Book 1B, p. 8-26) arteriole capillary tissue fluid body cell lymph capillary venule Key: direction of blood flow in the blood vessels component of plasma forced out of the capillaries to form tissue fluid tissue fluid returns to the capillaries tissue fluid drains into the lymph capillaries At the arteriole end, the (6) of blood in the capillaries is (7) than that of the fluid surrounding the body cells. This forces some components of the plasma (e.g. water, minerals, sugars, lipids and hormones) out of the capillary walls. Plasma proteins, red blood cells and (8) are too large to pass through the capillary walls. They remain in the blood. (9) can squeeze through the capillary walls and enter the tissue fluid. The composition of tissue fluid is similar to (10), except for the absence of red blood cells, blood platelets and plasma proteins. At the venule end, the (11) of the blood is (12) than that of the tissue fluid as plasma proteins remain in the blood. Water in the tissue fluid is drawn into the capillaries by (13). A small amount of tissue fluid drains into the (14) ( 淋巴微管 ). C What is the importance of tissue fluid? (Book 1B, p. 8-27) Provides a relatively (15) environment for body cells Serves as an important link for the exchange of materials between capillaries and body cells (Second Edition)

10 8.7 Lymphatic system (Book 1B, p. 8-28) The lymphatic system consists of (1) ( 淋巴 ), lymph vessels ( 淋巴管 ) and (2) ( 淋巴結 ). lymph vessels join to two large veins right atrium small intestine lymph vessel lymph node Key: direction of lymph flow The lymphatic system Component Lymph Lymph vessels Lymph nodes Feature Has the same composition as (3), i.e. similar to (4) except for the absence of red blood cells, blood platelets and plasma proteins Formed by joining of (5) Lymph inside is kept flowing very slowly by the contraction of the (6) (7) are present to prevent backflow of lymph Located at intervals along the lymph vessels (8) accumulate there to kill the germs in the lymph Functions of the lymphatic system: 1 Returns excess (9) to the blood circulation 2 Protects us against disease by filtering out germs from the lymph 3 Transports (10) from the lacteals in intestinal villi to the blood (Second Edition)

11 Answers Ch 8 Transport in humans circulatory system 2 lymphatic system 3 b 4 c / d 5 d / c 6 a plasma 2 antibodies 3 fibrinogen 4 heat 5 Biconcave disc 6 haemoglobin 7 lobed 8 bone marrow 9 spleen 10 bile pigment 11 oxygen 12 blood clotting arteries 2 veins 3 capillaries 4 Oxygenated 5 Deoxygenated 6 heart 7 skeletal muscles 8 capillaries 9 backflow 10 capillary beds 11 one-cell 12 differentially 13 High 14 periodically 15 resistance pericardium 2 cardiac muscles 3 coronary arteries 4 coronary veins 5 semilunar valves 6 tricuspid valve 7 aorta 8 bicuspid valve 9 septum 10 Thinner 11 deoxygenated 12 venae cavae 13 oxygenated 14 pulmonary veins 15 Thicker 16 left 17 deoxygenated 18 pulmonary artery 19 oxygenated 20 aorta 21 atria 22 ventricles 23 ventricles 24 Heart tendons twice 2 double circulation 3 lungs 4 aorta 5 oxygenated 6 deoxygenated 7 hepatic portal vein 8 small intestine tissue fluid 2 capillaries 3 short 4 surface area 5 Slow 6 pressure 7 higher 8 blood platelets 9 White blood cells 10 blood 11 water potential 12 lower 13 osmosis 14 lymph capillaries 15 constant lymph 2 lymph nodes 3 tissue fluid 4 blood 5 lymph capillaries 6 skeletal muscles 7 Valves 8 White blood cells 9 tissue fluid 10 lipids (Second Edition)

Ch 9 Transport of substances in humans

Ch 9 Transport of substances in humans Think about (Ch 9, p.2) 1. Blood transports various substances and distributes heat around the body. It also plays a role in body defence. 2. Blood is a liquid tissue