chapter 1 :TransportLearning objective:1. Understanding the importance of having transport system in some multicellular organisms2. Synthesise the concept of the circulatory system3. Understanding the mechanism of blood clotting4. Synthesise the concept of the lymphatic system5. Understanding the role of the circulatory system in the body’d defence mechanism6. Appreciate a healthy cardiovasular system7. Understanding the transport of substances in plants8. Synthesise the concept of the transport of substances in plants
1.1 The importance of having a transport system in some multicellular organismsLearning outcomes:1. Identify the problems that could be faced by multicellular organisms in obtaining their cellular requirements and getting rid of waste product2. Suggest how these problems are overcome in multicellular organisms
Transport• To describe how the substance in our body move from one part to the other part• Transport process varies in different types of organism
Difference transport in unicellular and multicellular organisms• 1. Unicellular organismEx?They have large total surface area to volume (TSA/V) ration that enable substance to diffuse easily into the cell• To obtain oxygen and nutrients directly from external environment• Carbon dioxide and other waste product also eliminated by diffusion through plasma membrane• So, They do not need any internal transport system
Multicellular organismsEx?• The TSA/V ration decreases• Cells often located away from external surface of the body• Diffusion rate also decrease which is a limiting factor to cellular activities in large animals• These organism have specialized structure to increase surface area ( alveolus)• They also need circulatory system to – Distribute nutrients and oxygen – Remove waste product
exercise• Examine cuboid A and B. Calculate the TSA/V of both cuboids. Assume that the cuboids are two organisms.• Which organisms obtain their cellular requirement (O2 and nutrients) and removing their waste product( co2 and urea) easily?• Why?
Assignments1. Why does unicellular organisms can undergoes diffusion process to transport their nutrients and waste products while multicellular organisms cannot?Elaborate your answer by giving suitable explanation. ( 8 marks)
1.2 The circulatory systemLearning Outcomes:1. State what a circulatory system is2. State the three components of the circulatory system in humans and animals3. State the medium of transport in humans and animals4. State the composition of human blood5. Explain the function of blood and haemolymph in transport6. Describe the structure of human blood vessel7. Explain how blood is propelled through human circulatory system8. Explain briefly how blood pressure regulated9. Compare and contrast the circulatory system in the following: human, fish and amphibians10. Conceptualise the circulatory systems in humans
Functions of the circulatory systemThe circulatory system has three functions: 1. Transporting substances around the body. These include oxygen, glucose, carbon dioxide, nutrients, water and waste products. 2. Controlling body temperature. 3. Protecting the body. Blood contains cells and anti-bodies that fight infection and clotting agents to stop bleeding.
3 components of circulatory system1. Medium of transport/ Blood2. Blood vessel3. Heart
1. Medium of transport/ BloodAnimals:Blood which consist of blood plasma, blood cells ( RBC, WBC) and platelesInvertebrates:Ex:Use haemolymph (fluid in hoemocoel)Hoemocoel: ronggaFunctions: transport material around the body
BloodBlood is the body’s means of transportingsubstances around. It transports: oxygen from the lungs to the heart and then to the body’s tissues carbon dioxide from the tissues to the heart and then to the lungs to be expired materials like hormones from one organ to another nutrients (especially glucose) and minerals from the intestines to the tissues waste products to the kidneys.
Composition of Human Blood• Blood: connective tissue that are composed of1. Cellular components (45%)• Platelets• Erythrocytes (RBC)• Leucocytes( WBC)1. Plasma (55%)• Water(90%)• Soluble solutes
Cellular components ( 45%)1. Platelets• Fragments of cells from bone marrow• No nucleus• Important for blood clotting process
1.PlateletsPlatelets are also carried in the blood. Formed in red bone marrow. Produce thrombokinase – a chemical needed for blood clotting. Platelets help to repair tissues and close wounds both internally and externally. When needed, they grow into irregular shapes and stick together to form a plug over the wound.
• They aggregate and release factors which promote the blood coagulation.•
2.Red blood cellsBlood is made up of a number of different elements.The most common cell in blood is the red blood cell.Also called erythrocytes.Disc-shaped.Made in the bone marrow.Contain a red-coloured compoundcalled haemoglobin which bondswith oxygen to formoxyhaemoglobin.Transport oxygen to the tissues.
• In the other vertebrates (e.g. fishes, amphibians, reptilians and birds), they have a nucleus.
3.White blood cellsBlood also contains white blood cells. Also called leucocytes. They are bigger than red blood cells and have large nuclei. Act as the body’s defence system. Some white blood cells surround and consume harmful microbes. Some produce chemicals called antibodies that fight infection. colorless
• Each type of leukocyte is present in the blood in different proportions:• neutrophil 50 - 70 % eosinophil 2 - 4 % basophil 0,5 - 1 % lymphocyte 20 - 40 % monocyte 3 - 8 %
• In fact, these granules have a different affinity towards neutral, acid or basic stains and give the cytoplasm different colors.• So, granulocytes distinguish themselves in neutrophil, eosinophil (or acidophil) and basophil.
Leukocytes ( WBC)1. Granulocytes2. A granulocytes
1. Granulocytes• Granular cytoplasm• filled with microscopic granules that are little sacs containing enzymes, compounds that digest microorganisms.• Lobed nuclei( kelepek)• Form in bone marrowConsist of:1. Basophils2. Neutrophils3. Eosinophils
Neutrophils• As a Phagocytes• Which digest bacteria and dead cells• By phagocytosis process
• In the different types of granulocytes, the granules are different and help us to distinguish them.• In fact, these granules have a different affinity towards neutral, acid or basic stains and give the cytoplasm different colors.• So, granulocytes distinguish themselves in neutrophil, eosinophil (or acidophil) and basophil
2. Agranulocytes• Clear cytoplasm• Nuclei are not lobed( terkelepek)• Consist of1. Lymphocytes2. monocytes
• Lymphocytes are cells which, besides being present in the blood,• Its populate the lymphoid tissues and organs too, as well as the lymph circulating in the lymphatic vessel.• An antibody is a molecule able to bind itself to molecules of a complementary shape called antigens, and recognize them.• As for all proteins, even the antibodies are coded by genes.• On the basis of a recombination mechanism of some of these genes, every lymphocyte produces antibodies of a specific shape.
Lymphocytes• Produce antibodies• Neutralize toxins• Produce immune responses against foreign substance• Largest leucocytes
Monocytes• Phagocytes• Engulf digested bacteria and dead cells• Origin: from bone marrow
characteristics RBC WBC1. SHAPE a) Erythrocytes are •Leucocytes have nuclei biconcave disc serves to: •Not have haemoglobin • Increase surface area to •Larger than erythrocytes volume ratio •Do not have fixed shaped • Increase diffusion rate of gaseous exchange b) No nucleus to gives space for great quantities of haemoglobin2.FUNCTION •Has haem group •Responsible for the defense •Contains iron atom of organism against disease •For the site of oxygen •If pathogen invade the body, binding number of leucocytes will •When the partial pressure of increase o2 is high, •Haemoglobin will combine with o2 to form •OXYHAEMOGLOBIN
3. DIAMETER 8 micrometer 15 micro meter Thickness: 2 micrometer4.Number of 5 million/mm3 6000-10000/mm3blood (Ration: 1WBC:700RBC)cell/mm3LIFESPAN 120 days A few days by phagocytosis Destroyed by phagocytes process (WBC) in the liver and spleen(limpa)MANUFACT Bone marrow Bone marrow(granulocytes)URED IN Rate: 2 million/ second •But may migrate to thymus gland or lymph node •For their growth and development stage •Lymphatic system ( agranucolytes)
PlasmaThe blood cells and platelets are suspended in asubstance called plasma. Plasma is made up of: 90% water inorganic salts(Na+, Mg2+, Cl-) glucose antibodies urea and other waste products plasma proteins.(ex: albumin, fibrinogen,prothrombin) Dissolved gases( oxygen and carbon dioxide) Hormones ( insulin)
• The plasma is a slightly alkaline fluid, with a typical yellowish color• The mineral substances are dissolved in ionic form, that is dissociated into positive and negative ions.• Ex: Ca2+
plasmaPlasma can be separated from theother components of blood usinga centrifuge.
Functions of blood in Transport1. Transport in oxygen2. Transport of carbon dioxide3. Transport of water to tissues4. Transport of excretory waste products5. Transport of hormones6. Transport of heat7. Transport of absorbed food materials
1. Transport of oxygen• Transport o2 from lung/alveolus cells/ all part of body• Oxygen combine with haemoglobin in erythrocytes to form = oxyhaemoglobin• Oxyhaemoglobin dissociates into haemoglobin and 02• O2 then supplied for cellular respiration (ATP) Hb + O2 ---> HbO <-------
2. Transport of carbon dioxide• Cellular respiration release co2Glucose + o2 - energy +co2+ water• Carbon dioxide transported from cells to lungs/ alveolus in the form of: a)Hydrogen carbonate ions b) Carbaminohemoglobin c)Dissolves directly in the blood plasma When the blood reaches the lungs, the co2 release and diffuse out of the blood into the alveoli
• Hydrogen carbonate ions are produced when carbon dioxide produced by tissue respiration is absorbed by blood plasma.• In your lungs, hydrogen carbonate ions turn back to carbon dioxide which is excreted when you exhale.
• Carbaminohaemoglobin is a combination of carbon dioxide and hemoglobin,• CO2HHb, being one of the forms in which carbon dioxide exists in the blood.
3. Transport of water to tissues• Water is transported by blood to provide a medium for biochemical reactions
4.Transport of excretory waste products1. Deamination• Process removing the amino group from the excess amino acid.• The amino group is converted to ammonia and then to urea by the liver• From liver, urea transported by blood to kidneys to be excreted
5.Transport of hormones• Blood transport hormones produced by endocrine gland to the target organs• Ex: insulin and glucagon carried by blood from pancreas to the liver
6. Transport of heat• Blood helps regulate body temperature by distributing heat
7. Transport of absorbed food materials• Soluble digested food, vitamins and mineral absorbed into capillaries of the villi in small intestine• Ex: simple sugar: glucose• Amino acids• Water soluble vitamins• Mineral salts
• They are transported by the hepatic portal vein from small intestine to liver and then to the heart• Other food materials are absorbed into lacteals in the villi• Ex: fatty acids, glycerol , vitamin ADEK (Fat soluble susbtances)• They are then transported by the lymph into the blood circulatory system via the left subclavian vein
Function of Haemolymph in transportHaemolymph:• the circulating fluid in open tissue spaces of invertebrates• A circulating blood-like nutritive fluid which fills the entire body cavity called haemocoel• A circulating system in invertebrates = open circulatory system because the haemolymph:1. Is not confined to vessels only2. Bathes the tissues and internal organs directly
• Nutrients such as digested food and hormones diffuse from haemolymph into cells.• Waste products diffuse out from cells into the haemolymph• Haemolymph does not transport respiratory gases.• Gaseous exchange via the tracheal system
2. Blood vessels• Consist of arteries• Capillaries• Veins functions: carries blood around the body
Blood vesselsThere are three types of blood vessels, blood from blood to the the heart heart artery veincarries blood carries blood away from back into the heart the heart carries blood to and from the body’s cells
arteries capillaries Veins•Carry oxygenated •Sites for the •Transportblood away from the exchange of deoxygenated bloodheart to all parts of respiratory gases, from all parts of thethe body nutrients and wastes body to the heart•Except pulmonary except pulmonaryartery vein•Blood pressure: •Lower than arteries •Lower than arteries•High blood pressure but higher than veinsin arteries•Thick muscular wall •One cell thickness •Thinner wall•Lumen size small •Lumen is very small •Lumen size is large•No valve except •No valve •Valve present toaorta prevent backflow of blood
arteries capillaries VeinsTo transport blood Allow rapid gaseous Allow blood fromquickly at high exchange between tissues to return topressure from the blood and the body the heartheart to tissues cells by diffusion
The ARTERYArteries carry oxygenated blood away from the heart. the elastic fibres allow the artery to stretch under pressurethick muscle andelastic fibres the thick muscle can contract to push the blood along.
The VEINVeins carry deoxygenated blood towards from the heart. veins have valves which act to stop the blood from going in the wrong direction. thin muscle and elastic fibres body muscles surround the veins so that when they contract to move the body, they also squeeze the veins and push the blood along the vessel.
The CAPILLARY Capillaries link Arterioles with Venus they exchange materials between the blood and other body cells.the wall of acapillary The exchange of materialsis only one cell thick between the blood and the body can only occur through capillaries.
Blood vessels thick outer wall thick inner layer of muscle and elastic fibres narrow central tube (lumen) ARTERY thin outer wall thin inner layer of muscle and elastic fibres wide central tube CAPILLARYVEIN (lumen) wall only one cell thick
Blood vessels: valvesWhen blood is flowing against gravity, or when a vein issqueezed by muscle action, there is a risk that blood willflow in the wrong direction. Veins have valves to preventbackflow. backflow vein valve prevented open blood to vein valve the closed heart The valves allow …but close if blood blood to flow in the starts to flow in the correct direction… wrong direction.
3. Heart• A heart is an organ that generates pressure to pump the blood through out the body
How blood is propelled throughthe human circulatory system?
Location of the Heart• The heart is located between the lungs behind the sternum and above the diaphragm.• It is surrounded by the pericardium.It is a fluid filled sac that surrounds the heart• Its size is about that of a fist, and its weight is about 250-300 g.
Anatomy of the heart• Heart made up of myogenic cardiac muscles which contract and relax automatically throughout life• It is not controlled by nervous system
• The human heart has four chambers:1. Left and right Atrium (atria= plural)• Upper chambers which receive blood returning to the heart• Thin -walled2. Left and right ventricles• Lower chambers which pump blood out of the heart• Thick walled
Septum:• Separates the right chambers from the left chambersThe valves: ensure that blood flows only in one direction.1. Tricuspid valve2. Bicuspid valve3. Semi lunar valve
The Heart Valves• The tricuspid valve- the valve between the right atrium and right ventricle• The bicuspid valve- the valve between left atrium and left ventricle• Semi lunar valve- the valves at the base of aorta and pulmonary artery
• The right pump forces deoxygenated blood to the lungs• The left pump forces oxygenated blood to other parts of the body
Pumping of the heart/ the heartbeat• http://www.pbs.org/wgbh/nova/heart/heartmap.html
SAN and AVN• Electrical signal begins in the sinoatrial (SA) node: "natural pacemaker." – causes the atria to contract. – Blood is then forced into the ventricles• The signal then passes through the atrioventricular (AV) node. – sends the signal to the ventricles via the “bundle of His” – causes the ventricles to contract. – And pump the blood out of the heart
• Right ventricle pumps the blood into pulmonary artery – which forces the blood to the lung• Left ventricle pumps the blood into aorta – which forces the blood to all part of the body
• Left ventricle is thicker and more muscular than the wall of the right ventricles• Because it needs to generate greater pressure to pump blood to all parts of the body• While the right ventricle pumps the blood to the lungs only
What is the cardiac cycle?• Cardiac cycle is the series of events that occur during one complete heartbeat• Including contraction (systole) and relaxation ( diastole) of both atria and ventricles
• The sino atrial node(SAN) can initiate the heartbeat on its ownSympathetic nerve carrying impulse to the heart can increase the heart rateParasympathetic nerve can slow it downThe heart rate increase when:• Increase in the secretion of hormone (adrenaline)• An increase in partial pressure of carbon dioxide in the blood• Body temperature is elevated
How does blood in the veins flow back to the heart?
1.Muscle relaxed , valves closed2.Muscles contract, upper valves open and blood is forced upwards , lower valve remain close3. Muscles relaxed, upper valves closed, lower valve opens as a result of muscle contraction elsewhere and blood flows forwards
Regulatory mechanism of blood pressure• Blood pressure is the force of the blood exerted of the arterial blood vessels• Arterial blood pressure is highest during ventricular systole , and lowest during diastole• Baroreceptors monitor the pressure of blood flowing to the body and to the brain• Baroreceptor located in the walls of the aorta and carotid arteries branch out from the aorta.