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 organisms

Learning outcomes:1. Identify the problems that could be faced by

multicellular organisms in obtaining their cellular requirements and getting rid of waste product

2. 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?

Assignments

1. 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.

3. Protecting the body. Blood contains cells and anti-bodies that fight infection and clotting agents to stop bleeding.

2. Controlling body temperature.

3 components of circulatory system

1. 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: rongga

Functions: transport material around the body

BloodBlood is the body’s means of transporting substances 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.Platelets

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.

Platelets are also carried in the blood.

• They aggregate and release factors which promote the blood coagulation.

•

2.Red blood cells

Also called erythrocytes.

Disc-shaped.

Made in the bone marrow.

Contain a red-coloured compound called haemoglobin which bonds with oxygen to form oxyhaemoglobin.

Transport oxygen to the tissues.

Blood is made up of a number of different elements. The most common cell in blood is the red blood cell.

• In the other vertebrates (e.g. fishes, amphibians, reptilians and birds), they have a nucleus.

3.White blood cells

Also called leucocytes.They are bigger than red blood cells and have large nuclei.Act as the body’s defence system.

Blood also contains white blood cells.

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. Granulocytes 2. 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

Neutrophils

Eosinophils

• Control allergic responses

• Kill parasitic worms by release enzyme.

eosinophils

Basophils

• Secretes heparin to prevent blood clotting

• Involve in combating inflammatory and allergic reactions

basophils

• 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

Difference between RBC AND WBC

characteristics RBC WBC

1. SHAPE a) Erythrocytes are biconcave disc serves to:

• Increase surface area to volume ratio

• Increase diffusion rate of gaseous exchange

b) No nucleus to gives space for great quantities of haemoglobin

•Leucocytes have nuclei •Not have haemoglobin•Larger than erythrocytes •Do not have fixed shaped

2.FUNCTION •Has haem group•Contains iron atom •For the site of oxygen binding•When the partial pressure of o2 is high, •Haemoglobin will combine with o2 to form•OXYHAEMOGLOBIN

•Responsible for the defense of organism against disease•If pathogen invade the body, number of leucocytes will increase

LIFESPAN 120 daysDestroyed by phagocytes (WBC) in the liver and spleen(limpa)

A few days by phagocytosis process

MANUFACTURED IN

Bone marrowRate: 2 million/ second

Bone marrow(granulocytes)•But may migrate to thymus gland or lymph node •For their growth and development stage•Lymphatic system ( agranucolytes)

3. DIAMETER 8 micrometerThickness: 2 micrometer

15 micro meter

4.Number of blood cell/mm3

5 million/mm3 6000-10000/mm3(Ration: 1WBC:700RBC)

PLASMA

Plasma

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 blood cells and platelets are suspended in a substance called plasma. Plasma is made up of:

• 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+

Plasma can be separated from the other components of blood using a centrifuge.

plasma

Functions of blood in Transport

1. 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 ionsb) Carbaminohemoglobinc)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 products

1. 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

Hepatic portal vein

Lacteal and villi

lymph

Subclavian vein

Function of Haemolymph in transport

Haemolymph:• 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

Structure of human blood vessels

Blood vessels

There are three types of blood vessels,

blood from the heart

blood to the heart

arterycarries blood

back intothe heart

carries blood away fromthe heart

carries blood to and from the body’s cells

vein

arteries capillaries Veins•Carry oxygenated blood away from the heart to all parts of the body•Except pulmonary artery

•Sites for the exchange of respiratory gases, nutrients and wastes

•Transport deoxygenated blood from all parts of the body to the heart except pulmonary vein

•Blood pressure:•High blood pressure in arteries

•Lower than arteries but higher than veins

•Lower than arteries

•Thick muscular wall •Lumen size small

•One cell thickness •Lumen is very small

•Thinner wall•Lumen size is large

•No valve except aorta

•No valve •Valve present to prevent backflow of blood

arteries capillaries Veins

To transport blood quickly at high pressure from the heart to tissues

Allow rapid gaseous exchange between blood and the body cells by diffusion

Allow blood from tissues to return to the heart

The ARTERY

thick muscle and elastic fibres

Arteries carry oxygenated blood away from the heart.

the elastic fibres allow the artery to stretch under

pressure

the thick muscle can contract to push the

blood along.

The VEIN

Veins carry deoxygenated blood towards from the heart.

thin muscle and elastic fibres

veins have valves which act to stop the blood from going in the wrong direction.

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

the wall of a capillaryis only one cell thick

they exchange materials between the blood and other body cells.

The exchange of materials between the blood and the body can only occur through capillaries.

Blood vesselsthick outer wall

thick inner layer of muscle and elastic fibres

narrow central tube (lumen)

thin outer wall

thin inner layer of muscle and elastic fibres

wide central tube (lumen)

wall only one cell thick

ARTERY

VEINCAPILLARY

Blood vessels: valves

When blood is flowing against gravity, or when a vein is squeezed by muscle action, there is a risk that blood will flow in the wrong direction. Veins have valves to prevent backflow.

blood to the

heart

backflow prevented vein valve

openvein valve

closed

The valves allow blood to flow in the correct direction…

…but close if blood starts to flow in the

wrong direction.

3. Heart

• A heart is an organ that generates pressure to pump the blood through out the body

How blood is propelled through the 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.

Location of the heart in the thorax

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

How does the heart beat?

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

The Conduction System

• 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 own

Sympathetic nerve carrying impulse to the heart can increase the heart rate

Parasympathetic 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 close

3. 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.