IMPORTANCE OF A TRANSPORT SYSTEM IN SOME MULTICELLULAR ORGANISMS

1.1

By: Rumaizah Muhamad

Dimension of cube (cm) 1 x 1 x 1 2 x 2 x 2 4 x 4 x 4

Total surface area of cube (cm2)

Volume of cube (cm3)

TSA/V ratio

small medium large

Calculate the TSA/V ratio.

• In larger multicellular organisms need a transport system so that dissolved materials could be moved rapidly to and from all parts of the body.

CONCEPT OF THE CIRCULATORY SYSTEM

1.2

Circulatory system in humans and animals

• Circulatory system (CS) includes:– Medium fluid that flows in CS (eg: animal :

blood; insects: haemolymph)– Vesels arteries, veins and capillaries– Pump muscular heart

Erythrocytes

Erythrocytes• Small, biconcave disc• Have no nucleus• Great quantities of haemoglobin (which contains iron)

• Site of production: bone marrow• Life span: 120 days• Site of destruction: liver and spleen (by phagocytes)• Ratio of erythrocytes to leucocytes 1000 : 1 (in normal person)

(Cells become bright red)

Leucocytes (White blood cells)

Erythrocytes

Leucocytes

Leucocytes (White blood cells)

• Less numerous than eryhtrocytes.• Have nuclei• Do not have haemoglobin• Larger than erythrocytes and do not have

fixed shapes.• Site of production : bone marrow• Site of growth and development: thymus

gland or lymph nodes

Cont.

Granulocytes (have granular cytoplasm and lobed nuclei) •Neutrophils •Eusinophils •Basophils

Agranulocytes (clear cytoplasm and no lobed) •Monocytes (largest)•Lymphocytes (smallest)

Basic types of leucocytes:

Quizzes

1. The neutrophils are _______A. PhagocytesB. LeucocytesC. LymphocytesD. Phosphate

2. Which leucocytes that help to control allergic reaction?A. BasophilsB. EosinophilsC. MonocytesD. Neutrophils

3. Basophils secrete _________ to prevent blood clottingA. WarfarinB. FibrinogenC. HeparinD. Walfarine

4. Which leucocytes that can move to the body tissues to become phagocytic macrophage?

A. BasophilsB. Neutrophils C. EosinophilsD. Monocytes

5. Some lymphocytes produce _________ to aid in destruction of __________

A. Antibodies, homogens B. Antibodies, pathogensC. Hormones, pathogensD. Enzymes, pathogens

Platelets

• Small, irregularly shaped

• F(x) : blood clotting• Life span: 5 -9 days

Plasma

• Pale, yellow liquid• Made up of 90% water & 10% dissolved solutes

(gases, minerals, hormones, plasma proteins and excretory wastes)

• BOOD SERUM : plasma without fibrinogen (clotting factors).

Plasma

Function of blood in transport

• Transport oxygen from the lungs to other parts of the body (form 4)

• Transport absorbed food materials from the digestive tract to body tissues (form 4)

• Transport waste products (form 4)

– Eg: carbon dioxide from body tissues to the lungs– Urea to the kidneys

• Transport heat, hormones and water

Transport of heat, hormones & water

• Body T can be regulated by blood by distributing heat from heat-producing sites (eg:muscles) to the skin.

• Hormones (eg:insulin & glucagon) produced by endocrine glands (pancreas) transported by blood to target organs (liver).

• Water is important to provide medium for biochemical reaction.

Function of haemolymph

• Circulating blood-like fluid found in invertebrates with open-circulatory systems

• Tubular heart pumps the haemolymph into haemocoel.

• Haemolymph – bathes the tissues and internal organ directly.

• Nutrients and hormones diffuse from haemolypmh into the cells

• Waste products diffuse out from the cells into haemolymph.

Structure of human blood vessels

Arteries Capillaries Veins Transport blood away from the heart

Connect arterioles to venules

Transport blood to the heart

Transport oxygenated blood (except pulmonary artery)

Act as the sites for exchange of substances with the cells

Transport deoxygenated blood (except pulmonary vein)

Thick muscular wall Thinnest wall, one cell thickness

Thinner wall

No valves except semilunar valves at the base of the aorta and pulmonary artery

No valves Valves present to prevent back flow of blood

Blood flows in pulses under high pressure

No pulses. Pressure lower than arteries but higher than veins

No pulses. Blood flows under lower pressure than arteries.

Blood vessels : tubes that transport blood from one part to another.

Artery, vein and capillary

How blood is propelled through the human circulatory system

• Organ responsible to pump the blood : heart

Structure of the human heart

How blood is propelled through the human circulatory system

• VIDEO

Lungs

Whole body

Left atrium

Left ventricleRight atrium

Right ventricle

Pulmonary veins

Aorta

Bicuspid valve

Tricuspid valve

Pulmonary artery

Vena cava

O2 blooddeO2 blood

FAQ SPM1. The diagram below shows the external view of the

human heart.

What is the blood vessel labeled W?A. Carotid arteryB. Coronary arteryC. Subclavian arteryD. Systemic artery

3.

The pumping of the heart

Sinoatrial node

Atrio-ventricular node

Bundle of His containing Purkinje tissue

Interventricular septum

Conducting system of the heart

• Video

Contraction of skeletal muscles around veins

Circulatory system in insects

1. When the heart relax, haemolymph re-enters ostia

2. Valves ensure the haemolymph flow in one direction

Material exchange occurs here. Haemolymph in haemocoel carry nutrients and waste products

Circulatory system in fish

• Single circulatory system.• Deoxygenated blood

leaves the heart at high pressure and passes through the gills where the gaseous exchange occurs.

• Oxygenated blood flows through the organs and blood pressure drops.

Sinuses

Circulatory system in amphibians (eg:frogs)

• Double circulatory system:– Pulmonary circulation– Systemic circulation

• Have three-chambered heart (2 atria & 1 ventricle)

• Mixing of oxygenated and deoxygenated blood in ventricle. The mixed blood enters the systemic circulation.

Circulatory system in humans

FAQ SPM1. The diagram below shows a longitudinal section of the

human heart.

Which of the labeled parts, A, B, C or D, receives blood from the lungs?

2. The diagram shows the circulatory system of a fish.

What are the organs P, Q and R? P Q R

A Gills Lungs Stomach

B Stomach Lungs Gills

C Gills Heart Stomach

D Stomach Heart Gills

Circulatory system in humans

• Double circulatory system (blood passes through the heart twice for each circuit)– Pulmonary circulation– Systemic circulation

• Two divisions of heart: – Right side pump deoxygenated blood to the lungs– Left side pump oxygenated blood to the body (except lungs)

• Advantage: blood returns to the heart to be pumped again will increase the blood pressure and flow rate, thereby speeding up delivery O2 to the tissues and organs.

Assignment 1.3

1. Draw and label a longitudinal section of human heart.

2. List the functions of the different types of leucocytes.

THE MECHANISM OF BLOOD CLOTTING

1.3

The necessities of blood clotting

• To prevent:– serious blood loss– the entry of microorganisms and foreign particles

into the blood• To maintain:– normal blood pressure– circulation of blood in a a closed circulatory

system

The mechanism of blood clotting

VIDEO

FAQ SPM

1. The conversion of the soluble fibrinogen present in blood plasma into the insoluble fibrin is by

A. calcium ionB. thrombinC. thromboplastinsD. vitamin K

FAQ SPM

2. Fibrinogen, fibrin, thrombin and prothrombin are necessary for blood clotting. Which of the following is the correct sequence for the involvement of these four substances during blood clotting?

A. Prothrombin, thrombin, fibrinogen, fibrinB. Thrombin, prothrombin, fibrin, fibrinogenC. Fibrinogen, fibrin, prothrombin, thrombinD. Fibrin, fibrinogen, thrombin, prothrombin

Impaired blood clotting mechanisms in human

The consequences

HEART ATTACK

DEEP VEIN THROMBOSIS

STROKE

Assignment 1.4

1. List the advantages of blood clotting at the site of damaged blood vessels.

2. Draw a schematic diagram to illustrate the mechanism of blood clotting.

3. What would happen if a blood clot forms a) In the brainb) In the coronary artery