Transport in animalsTransport in animals

ObjectivesObjectives

Discuss the need for transport system in Discuss the need for transport system in multi-cellular organisms.multi-cellular organisms.

Describe the components of blood and Describe the components of blood and their functionstheir functions

Differentiate among blood vesselsDifferentiate among blood vessels Describe the structure & function of the Describe the structure & function of the

heart.heart.

Why do animals need a transport Why do animals need a transport system?system?

A transport system carries things to and from A transport system carries things to and from one place to the next.one place to the next.

Smaller plants and animals Smaller plants and animals have a larger have a larger surface are to volume ratiosurface are to volume ratio

This means that from any point on their surface, This means that from any point on their surface, materials can diffuse inwards and reach the materials can diffuse inwards and reach the destination quicklydestination quickly

The very small organisms such as the unicellular The very small organisms such as the unicellular AmoebaAmoeba don’t need a transport system. Different substances don’t need a transport system. Different substances diffusediffuse in and out of their bodies across surface membranes.in and out of their bodies across surface membranes.

In larger organisms the process of diffusion will occur only In larger organisms the process of diffusion will occur only up to a few cells into the body from the surface. Also with up to a few cells into the body from the surface. Also with skin, fur and feathers acting as barriers the process is skin, fur and feathers acting as barriers the process is slowed. slowed.

It is inefficient as necessary substances will not reach to It is inefficient as necessary substances will not reach to cells in required time.cells in required time.

Only organisms that are a few cells large are able Only organisms that are a few cells large are able to use diffusion as an efficient means of transport, to use diffusion as an efficient means of transport, after which a after which a transportation systemtransportation system is necessary is necessary

**The larger an organism gets, the smaller the The larger an organism gets, the smaller the surface area to volume ratio is, so movement of surface area to volume ratio is, so movement of materials by diffusion takes longer.materials by diffusion takes longer.

Therefore the development of a transport Therefore the development of a transport system was essential for larger organisms system was essential for larger organisms

This system functions to carry essential This system functions to carry essential substances to each cell and carries away toxic substances to each cell and carries away toxic substances from them in an substances from them in an effectiveeffective and and efficient efficient manner.manner.

The circulatory systemThe circulatory system

Circulatory SystemCirculatory System The circulatory system is the transport system The circulatory system is the transport system

found in mammals. Humans have a found in mammals. Humans have a cardiovascular system in which cardiovascular system in which twotwo types of types of circulation occurs ( Systemic and Pulmonary)circulation occurs ( Systemic and Pulmonary)

The circulatory system is composed The circulatory system is composed of three main parts:of three main parts:

The heartThe heart The bloodThe blood The blood vessels.The blood vessels.

Heart Heart

This organ pumps blood around the body This organ pumps blood around the body at different speeds and at different at different speeds and at different pressures according to the body’s needs.pressures according to the body’s needs.

The heart is made of CARDIAC MUSCLE.The heart is made of CARDIAC MUSCLE. The cardiac muscles in the heart contracts The cardiac muscles in the heart contracts

and relaxes continuously.and relaxes continuously.

Cardiac muscleCardiac muscle This muscle has its own blood supply This muscle has its own blood supply

(coronary circulation).(coronary circulation). Blood reaches the muscle via the Blood reaches the muscle via the coronary coronary

arteriesarteries.. These carry blood to capillaries that supply These carry blood to capillaries that supply

the heart muscle with oxygen & nutrients.the heart muscle with oxygen & nutrients. This allows the heart muscle to keep on This allows the heart muscle to keep on

working.working. Blood returns to the atrium via Blood returns to the atrium via coronary veinscoronary veins..

Structure of the HeartStructure of the Heart

Structure of the heartStructure of the heart The heart has four chambers:The heart has four chambers: The two The two upperupper chambers are the Right and Left chambers are the Right and Left

AtriumAtrium The two The two lower lower chambers are the Right and Left chambers are the Right and Left

Ventricles.Ventricles.

It’s also divided into a right and left side by the It’s also divided into a right and left side by the SEPTUM;SEPTUM; The left side of the heart circulates The left side of the heart circulates oxygenated oxygenated

blood.blood. The right side of the heart circulates The right side of the heart circulates

deoxygenated blood.deoxygenated blood.

There are four valves separating each There are four valves separating each chamber. What is their function?chamber. What is their function?

As blood enters the atrium, its walls stretch to receive As blood enters the atrium, its walls stretch to receive blood; then it contracts to push blood through onto the blood; then it contracts to push blood through onto the lower ventricles.lower ventricles.

ValvesValves

Prevents backflow of blood to the previous Prevents backflow of blood to the previous chamber.chamber.

The Tricuspid valve separates which two The Tricuspid valve separates which two chambers?chambers?

Mitral valve?Mitral valve? Aortic Valve?Aortic Valve? Pulmonary Valve?Pulmonary Valve?

RULESRULES Blood Blood entersenters the heart through the atria. the heart through the atria.

Blood Blood leavesleaves the heart when the ventricles contract. the heart when the ventricles contract.

The right ventricle pumps blood only to the lungs The right ventricle pumps blood only to the lungs

The left ventricle pumps blood to all parts of the body. The left ventricle pumps blood to all parts of the body.

This requires much more pressure, which is why the wall This requires much more pressure, which is why the wall of the left ventricle is much thicker than that of the right of the left ventricle is much thicker than that of the right ventricle.ventricle.

FLOW OF BLOOD THROUGH HEARTFLOW OF BLOOD THROUGH HEART

Deoxygenated blood from body enters Deoxygenated blood from body enters from Vena cava vein into RAfrom Vena cava vein into RA

Atria contracts and pushes blood from RA Atria contracts and pushes blood from RA into RVinto RV

Ventricles contract and blood is pushed Ventricles contract and blood is pushed into into pulmonary arterypulmonary artery which goes towards which goes towards the lungs.the lungs.

Gaseous exchange occurs at alveoli and Gaseous exchange occurs at alveoli and pulmonary veinpulmonary vein brings back Oxygenated brings back Oxygenated blood to LA.blood to LA.

When atria contract simultaneously again , the When atria contract simultaneously again , the oxygenated blood is pushed into LVoxygenated blood is pushed into LV

When ventricles contract the blood is pumped When ventricles contract the blood is pumped out to Aorta and to the rest of the body.out to Aorta and to the rest of the body.

• Pulmonary artery and vein are the few blood Pulmonary artery and vein are the few blood vessels in which the roles of artery and vein are vessels in which the roles of artery and vein are reversed.reversed.

*Normally arteries carry oxygenated blood to *Normally arteries carry oxygenated blood to organs and veins bring back deoxygenated organs and veins bring back deoxygenated blood from body to heartblood from body to heart

Systole and Diastole Systole and Diastole

The systole occurs when the chambers of The systole occurs when the chambers of the heart contracts. Pumps blood out of the heart contracts. Pumps blood out of heartheart

The diastole occurs when the heart’s The diastole occurs when the heart’s chambers relax, allows new blood to enter chambers relax, allows new blood to enter heartheart

This contraction and relaxation is what This contraction and relaxation is what causes the “lub-dub” sound of the causes the “lub-dub” sound of the heartbeat.heartbeat.

Animation of heartbeat.Animation of heartbeat.

http://www.nhlbi.nih.gov/health/dci/http://www.nhlbi.nih.gov/health/dci/Diseases/hhw/hhw_pumping.htmlDiseases/hhw/hhw_pumping.html

Double circulation in humans.Double circulation in humans.

This refers to a system that pumps blood to the This refers to a system that pumps blood to the heart heart twicetwice. It has two main parts:. It has two main parts:

Pulmonary circulationPulmonary circulation: blood is first circulated : blood is first circulated through the lungs where it is through the lungs where it is oxygenatedoxygenated..

Systemic circulationSystemic circulation: blood is then circulated : blood is then circulated

throughout the body where it unloads its oxygen, throughout the body where it unloads its oxygen, and exchanged with and exchanged with deoxygenateddeoxygenated blood. blood.

Double CirculationDouble Circulation

Types of blood vesselsTypes of blood vesselsOuter wall

with muscle fibres

Muscle & elastic layer

Small Lumen Large Lumen

Capillary-the linkage between Capillary-the linkage between artery and veinartery and vein

Exchange of material at cell siteExchange of material at cell site At the cells, a capillary network is formed. Plasma from At the cells, a capillary network is formed. Plasma from

the blood capillaries ooze out under arteriole pressure the blood capillaries ooze out under arteriole pressure and surrounds the cellsand surrounds the cells

This is known as This is known as TISSUE FLUIDTISSUE FLUID. This provides a moist . This provides a moist medium for substances to diffuse across the cell and medium for substances to diffuse across the cell and capillary membranes. Increases diffusion rate.capillary membranes. Increases diffusion rate.

On the Venous end of the capillary network the plasma On the Venous end of the capillary network the plasma is reabsorbed back into capillaries.is reabsorbed back into capillaries.

BloodBlood The blood is the The blood is the mediummedium

in which substances are in which substances are transported throughout transported throughout the body. It has many the body. It has many other functions besides other functions besides transportation alone.transportation alone.

BLOOD COMPOSITIONBLOOD COMPOSITION

•The The composition of materialscomposition of materials transported by blood are: transported by blood are:WaterWaterGases (Oxygen, Carbon dioxide)Gases (Oxygen, Carbon dioxide)SaltsSaltsNutrientsNutrientsNitrogenous waste products e.g. ureaNitrogenous waste products e.g. ureaHormones & antibodiesHormones & antibodiesHeatHeat

•These substances that are transported are These substances that are transported are dissolved in the blood plasmadissolved in the blood plasma

BLOOD COMPONENTSBLOOD COMPONENTS Blood is Blood is

comprised of comprised of PlasmaPlasma Red blood cellsRed blood cells White Blood White Blood

cellscells PlateletsPlatelets

PlasmaPlasma

This is the yellowish liquid part of This is the yellowish liquid part of blood,90% is waterblood,90% is water

Transports dissolved substances :Transports dissolved substances : Dissolved foodDissolved food CO2CO2 HormonesHormones Mineral saltsMineral salts Nitrogenous wasteNitrogenous waste

Red blood cellsRed blood cells

The red blood cells are responsible for the The red blood cells are responsible for the transport of oxygentransport of oxygen

It contains haemoglobin which combines It contains haemoglobin which combines reversiblyreversibly with oxygen (oxyhaemoglobin) with oxygen (oxyhaemoglobin) and is carried to cells.and is carried to cells.

Oxygen is readily released from haem at Oxygen is readily released from haem at tissues where O2 level is low.tissues where O2 level is low.

At the cells the rbc encounters carbon dioxideAt the cells the rbc encounters carbon dioxide Why? Why?

The carbon dioxide diffuses into blood (along The carbon dioxide diffuses into blood (along conc. gradient) and travels as hydrogen conc. gradient) and travels as hydrogen carbonate ions in the plasmacarbonate ions in the plasma

Red Blood CellRed Blood Cell

RBC has RBC has no nucleusno nucleus which increases amt which increases amt of haem carried in it and hence can of haem carried in it and hence can transport more O2transport more O2

RBC die after 3-4 mthsRBC die after 3-4 mths

Rbc is produced in the bone marrow of Rbc is produced in the bone marrow of long bones: femur, humerus, pelvis, ribs long bones: femur, humerus, pelvis, ribs etcetc

White blood cellsWhite blood cells These are the bodyguards against pathogen These are the bodyguards against pathogen

infectioninfection

They help fight against disease by They help fight against disease by surrounding and destroying foreign objects surrounding and destroying foreign objects that are introduced into the systemthat are introduced into the system

They are categorized according to their They are categorized according to their actionsactions

PhagocytesPhagocytes: lobed nucleus, surrounds and : lobed nucleus, surrounds and “eats” pathogen“eats” pathogen

LymphocytesLymphocytes: round nucleus, produce : round nucleus, produce antibodiesantibodies which stick to and deactivates which stick to and deactivates pathogenpathogen..

PlateletsPlatelets

Platelets are fragments of cells formed in Platelets are fragments of cells formed in bone marrowbone marrow

They have no nucleusThey have no nucleus Function to help clot blood preventing Function to help clot blood preventing

blood loss.blood loss. What is the importance of clotting blood?What is the importance of clotting blood? Draw diagram of formation of blood clot.Draw diagram of formation of blood clot.

Draw diagramto show blood clot process. Draw diagramto show blood clot process. include Ca+ and vit K importanceinclude Ca+ and vit K importance

BLOOD TRIVIABLOOD TRIVIA

Human body has between 4.5 to 5.6 litres Human body has between 4.5 to 5.6 litres of bloodof blood

Blood vessels in body laid end to end Blood vessels in body laid end to end would stretch 60,000mileswould stretch 60,000miles

The normal heart pumps 5 liters of blood The normal heart pumps 5 liters of blood per minuteper minute

ABO BLOOD GROUPSABO BLOOD GROUPS There are 4 blood types: A, B , O ,ABThere are 4 blood types: A, B , O ,AB These arise from the presence or absecence of These arise from the presence or absecence of

antigens antigens aa and and bb on blood cell membranes on blood cell membranes Each blood type produces different and specific Each blood type produces different and specific

antigens which fight foreign objectsantigens which fight foreign objects Important to know blood group especially during Important to know blood group especially during

a blood tranfusiona blood tranfusion The donor’s blood must match the recipient for The donor’s blood must match the recipient for

transfusion to be successful.transfusion to be successful. Important steps to take when having blood Important steps to take when having blood

transfusions?transfusions?

Diseases associated with Diseases associated with circulatory systemcirculatory system

HypertensionHypertension This is persistent high pressure of blood on This is persistent high pressure of blood on

the inside walls of arteries.the inside walls of arteries. This high pressure can cause vessels as This high pressure can cause vessels as

capillaries to burst.capillaries to burst. A stroke is where a blood vessel in brain A stroke is where a blood vessel in brain

burst, affecting portion of brain and damaging burst, affecting portion of brain and damaging it because oxygen is not being delivered.it because oxygen is not being delivered.

Hypertension can cause vessels to burst in Hypertension can cause vessels to burst in other organs e.g. kidney failureother organs e.g. kidney failure

ArteriosclerosisArteriosclerosis Hardening of artery walls Hardening of artery walls Clotting of blood in arteries can lead to Clotting of blood in arteries can lead to

ateriothrombosisateriothrombosis

ImmunizationImmunization Immunization is the ability to withstand or Immunization is the ability to withstand or

fight any illness or disease.fight any illness or disease. When there are foreign bodies or antigens When there are foreign bodies or antigens

entering the body , the blood makes entering the body , the blood makes antibodies to fight and rid the body of the antibodies to fight and rid the body of the deleterious effects .deleterious effects .

The first line of defense is the physical barrier of skin The first line of defense is the physical barrier of skin to germs.to germs.

Other body orifices are also protected by some Other body orifices are also protected by some means or the other: nose, lungs, vagina, eyes, means or the other: nose, lungs, vagina, eyes, stomachstomach

The second defense is the presence of white blood The second defense is the presence of white blood cells that attack and eat the pathogens that may enter cells that attack and eat the pathogens that may enter body. This is a non specific defense mechanismbody. This is a non specific defense mechanism

The third is the production of antibodies that are The third is the production of antibodies that are specific to antigens or germs that enter the body. It is specific to antigens or germs that enter the body. It is produced by lymphocytes.produced by lymphocytes.

Antibodies perform 4 different type of functions:Antibodies perform 4 different type of functions: They surround and kill the antigenThey surround and kill the antigen They neutralise the toxic effect of the antigen on the They neutralise the toxic effect of the antigen on the

body.body.

Immunity is obtained either naturally or Immunity is obtained either naturally or artificially.artificially.

Natural immunity is obtained when the body Natural immunity is obtained when the body when infected, produces the antibodies to fight when infected, produces the antibodies to fight the infectionthe infection

Immunization processImmunization process

When infection first occurs it takes time for When infection first occurs it takes time for the body to make the antibodies to fight the body to make the antibodies to fight the antigens. Afterwards the blood cells the antigens. Afterwards the blood cells retains memory antibodies which are retains memory antibodies which are capable of producing the antibodies faster capable of producing the antibodies faster if it is infected with the same disease if it is infected with the same disease again.again.

Natural immunityNatural immunity

This is the immunity gained when This is the immunity gained when