TRANSPORTATION

SHEETAL TIWARI
Transportation
“ Transportation is the movement of materials from one part to another, usually from the region of their
availability to the region of their use, storage or elimination”

Occurs in all organisms , from microscopic ones to large sized trees and animals.

Functions, Need or Importance of Transportation

 Food
 Metabolic gases
 Waste products
 Water
 Hormones

Modes of Transport
Lower organisms – Diffusion
Higher organisms – Diffusion
- for cell to cell movement of materials.
A long distance transport system occurs
Different in Animals & Plants
Animals – Circulatory system
Plants – Vascular strands

Transportation in Human beings

 In human beings, 2 circulatory systems
1. Blood Vascular System – Heart, Blood, Blood Vessels ( arteries, veins, capillaries)
2. Lymphatic System – Lymph, Lymph capillaries,Lymph vessels, Lymph nodes or Lymph glands

BLOOD VASCULAR SYSTEM

I. BLOOD
 Mobile fluid connective tissue
 Reddish in colour
 Supplies nutrients, hormones, O2 to all living cells,
and takes away CO2 an waste products from
them.
 Adult human has 5-6 litres of blood.
 2 components – plasma and corpuscles

Plasma
 Pale yellow transparent fluid
 matrix of blood
 92% H20 & 8% solutes
solutes – proteins, nutrients, excretory products, inorganic salts, other substances (metabolic gases, hormones,
cholesterol, heparin

Corpuscles
 Constitutes 45% of the blood
 3 types – RBC, WBC and Blood platelets
RBC’s ( Erythrocytes )
- Circular, biconcave discs
- Nucleus, Mitochondria, ER, Ribosomes – absent
WBC’s (Leucocytes)
- Colourless, nucleated, of different shapes and sizes
- Involved in defense and offence
- So Phagocytes or Immunocytes
Blood Platelets
- Thrombocytes
READING OF NCERT TEXTBOOK IS MUST
TRANSPORTATION
SHEETAL TIWARI
- Colourless, non-nucleated, cell fragments
- Help in blood clotting

Functions of blood
 Transport of nutrients
 Transport of O2
 Transport of CO2
 Transport of waste products
 Transport of hormones
 Maintenance of water balance
 Regulation of body temperature
 Maintenance of pH
 Body Defence
 Plugging areas of injury

Blood clotting
( Maintenance by platelets)
Injury

Injured tissue and disintegrating platelets + Air

Thromboplastin (In presence of calcium)

Prothrombin ( Vit K in liver) Thrombin

Fibrinogen (soluble) Fibrin (Insoluble)

Rapid Polymerisation
Clotting Time:
2-5 min for superficial cuts Long fibres
4-10 min for deeper cuts
Blood Clot

II BLOOD VESSELS ( 3 TYPES)

Arteries Veins Capillaries
Carry blood from heart to Carry blood from various Narrow blood vessels with
various organs parts of the body towards the single layered wall
heart
Generally carry oxygenated Carry deoxygenated blood. Forms network inside body
blood . Exception – Exception – pulmonary vein organs
pulmonary artery carries bring oxygenated blood from
deoxygenated blood from lungs to the heart
heart to lungs
Wall is thick and elastic Wall is less thickened and Has very fine pores for
less elastic exchange of substances
Lumen narrow Lumen wide Plasma, WBC can come out

Mostly deep seated Internal valves prevent back

flow
Superficially located

READING OF NCERT TEXTBOOK IS MUST

TRANSPORTATION
SHEETAL TIWARI
III HEART
 Reddish in colour
 Size of our fist (12 x 9 cm)
 Wt: 300 gm / 250 gm
 Lies in thoracic cavity between two lungs
 Pointed appendix tilted towards left
 Brings about circulation of blood by its pumping activity
 Covered by fluid filled membranous sac – pericardium
- frictionless movement & protection from shock
 has 4 chambers – 2 upper are smaller and thin walled called
auricles or atria (atrium) - 2 lower are larger and thick walled
called ventricles.
 has transverse and oblique groove and septum separating 2
ventricles and 2 auricles.
 These septum separate the right side of the heart from the
left side.
 right auricle opens into right ventricle through an aperture
guarded by TRICUSPID VALVE. Left
 llly; left auricle opens into left ventricle through an aperture guarded by a BICUSPID VALVE.
 Both valves are guarded by fine fibres CHORDAE TENDINEAE.
 The right ventricle opens into a pulmonary arch, opening guarded by semi lunar pulmonary valve.
 llly; the left ventricle opens into aorta with semi-lunar aortic valve.

CIRCULATION OF BLOOD
 Heart receives blood from veins and pumps the same into arteries.
 Deoxygenated blood from the whole body enters right auricle through superior vena cava, Inferior vena cava
and coronary sinus. The right atrium expands during the flow of deoxygenated blood into it.
 Right atrium contracts to pour and right ventricle expand to receive the deoxygenated blood.
 Right ventricle pumps deoxygenated blood into pulmonary arch, then taken to lungs by pulmonary arteries
for oxygenation.
• The oxygenated blood from the lungs is received by left atrium, which dilates to accommodate it.
• Left atrium contracts and left ventricle dilates. Blood passes from left atrium to left ventricle.
• Left ventricle contracts and sends the oxygenated blood to different parts through aorta.
• Diastole and systole of auricles occurs simultaneously and llly diastole and systole of ventricles occur
simultaneously.
• Importance of partition between the left side and right sides of the heart.

Cardiac cycle and Heart beat

 Cardiac cycle- 0.8 sec duration.
 Consists of one filling and emptying of the chambers of the heart.
 Heart beat – Rhythmic expansion and contraction of heart is called heart beat.
 Auricles and ventricles undergo diastole and systole separately but being forceful only ventricular
contraction and expansion constitute the heart beat.
 Adult man 70-72 / m ; woman 80 / min.

Blood Pressure
 Pressure exerted by forceful flow of blood on the elastic wall of the arteries.
 Measured in mm of Hg by an instrument called Sphygmomanometer.
 1st sound of blood flowing into bronchial artery gives systolic pressure.
 With further release of air, a stage comes when the sound disappears. It is diastolic pressure.
 The normal systolic pressure is 120 mm Hg and normal diastolic pressure is 80 mm Hg.
 Higher value 150/90 mm Hg – called Hypertension / High blood pressure.
 Lower value 110 / 70 mm Hg – Hypotension / Low blood pressure.

READING OF NCERT TEXTBOOK IS MUST

TRANSPORTATION
SHEETAL TIWARI
WHAT IS DOUBLE CIRCULATION
 In amphibians, reptiles, birds and mammals the blood passes through the heart twice in each complete cycle
. Blood supplied to the lungs as well as to the body is pumped by the heart.
 Since the blood supplied to the body is also pumped by the heart, it raises pressure & accelerates the supply
of food & oxygen to the body.

Double circulation of blood in man

o passage of the same blood twice through the heart first on the right side, then on the left side in order to
complete one cycle.
o it has 2 components 1. pulmonary
circulation 2.systemic circulation
o 1. pulmonary circulation – movement of
blood from heart to the lungs and back.
Deoxygenated blood – enters the right
auricle – passes into right ventricle –
pumps in pulmonary arch – pulmonary
arteries – passes into lungs – gets
oxygenated – comes back to left auricle
– by 4 pulmonary veins.
o 2. systemic circulation – circulation of
blood between heart and different parts
of the body except lungs – oxygenated
blood from left auricle passes to left
ventricle – pumped into aorta – supplied
to different parts of the body – at
tissues get deoxygenated – veins take
deoxygenated blood to the heart –
poured into right auricle.
o Importance of Double Circulation – ensures quick and efficient supply of oxygenated blood to all body parts
- whole of the deoxygenated blood goes directly to lungs for quick oxygenation – meets higher needs of
energy – thermoregulation.

LYMPHATIC SYSTEM
 Consists of lymph capillaries, lymph vessels, lymph nodes an lymph.
 Specialized to collect lymph from tissue fluid and carry the same to blood.
LYMPH
 light yellowish viscous fluid .
 formed from tissue fluid.
 tissue fluid is blood plasma + WBC’s filtered out of the blood capillaries.
 Specialized to collect tissue secretions which cannot pass directly into blood. E.g. hormones from endocrine
glands, plasma proteins from liver, fats from intestine.
 also carries waste products.

LYMPH CAPILLARIES
 fine blind tubes
 permeable to even macromolecules
 join to form lymph vessels
LYMPH NODES / LYMPH GLANDS
 at places lymph vessels bear swellings called lymph nodes.
 also called lymph glands.
 place / seat for lymphocyte maturation.
 occur at places e.g. tonsils, spleen, thymus, adenoids.
 Filter out germs and foreign particles.

READING OF NCERT TEXTBOOK IS MUST

TRANSPORTATION
SHEETAL TIWARI
LYMPH FUNCTIONS
 Exchanges materials between blood and tissue fluid.
 Maintains the blood volume by collecting the blood plasma oozed or filtered out of blood capillaries.
 Lymphocytes mature inside lymph nodes.
 Carries secretions of tissue for passage into blood.
 Absorbs digested fat from alimentary canal and pours into blood.
 Wastes from tissues first passed into lymph before they are poured into blood for separation in kidneys.
 Germs are taken to lymph nodes for destruction.

TANSPORTATION IN PLANTS
 Some materials pass in and out of plants through diffusion.
 Diffusion of gases occurs through stomata and lenticels.
 Water vapour also passes out through stomata.
 Food is prepared in green parts – leaves and young shoots.
 Other materials for building plant body obtained from soil, e.g. N, P, other minerals, water.
 The above two needs to be transported to long distances – size of the plant.
 Therefore, a proper transport system required, have large proportion of dead cells, do not move, low energy
needs, transport systems are slow.
 Have 2 independent pathways having conducting tubes – 1. XYLEM moves water and minerals from soil to
aerial parts 2.PHLOEM carries food from the region of their availability (leaves, storage organs) to the areas
of utilization (all living cells).

XYLEM
 Complex tissue which transports sap – water and minerals.
 Has 4 types of cells – xylem fibres, xylem parenchyma, tracheids and vessels.
 Only xylem parenchyma are living cells. Others are dead, empty and lignified.
 Vessels are long multicellular tubes – formed by end to end union of several cells without any cross walls.

PHLOEM
 Complex tissue which takes part in transport of food,
 Has four types of cells – sieve tubes, companion cells, phloem parenchyma and phloem fibers.
 Only phloem fibers are dead cells, others are living cells.
 Sieve tubes are conducting channels – are elongated multicellular tubular channels formed by end to end
union. Have sieve plates.

Transport of water and minerals

 Plants have a continuous system of water conducting channels from near the root tips to near the shoot tips.
 In the roots the surface cells are in contact with soil particles and soil water.
 Various steps involved in transport of water and minerals.

Steps
 Mineral absorption occurs in the growing parts of the root. Both the surface
cells and root hairs take part in mineral absorption. Active process. Against
concentration gradient. More salts present inside the root than in the soil
solution.
 Absorption of water – root hair zone is the region of water absorption. Inside of
the root has higher osmotic concentration than soil solution. Root
hairs pick up water from soil, transferred inwardly due to still
higher osmotic concentration. Reaches cells surrounding the xylem
channel. Salts accumulation in the basal part of xylem
channel cause osmotic entry of water into xylem. It also
creates a positive pressure called root pressure. However, unable to push water to any
great heights.

READING OF NCERT TEXTBOOK IS MUST

TRANSPORTATION
SHEETAL TIWARI
 Ascent of sap – it is the upward movement of absorbed water or sap from root to the top of the plant. Loss
of water by mesophyll cells increases their suction pressure. Water withdrawn from xylem channels. Billions
of mesophyll cells withdrawing water from xylem channels, xylem channel comes under tension or negative
pressure. It results in upward pull of water. As it develops due to transpiration, called transpiration pull.

Transport of food and other substances (Translocation)

 Food materials are translocated from the
region of their manufacture or storage to the
region of their utilisation.
 The direction of translocation can be
downward, upward or both.
 The translocation nutrients consist of
soluble carbohydrates (mostly sucrose), amino
acids, organic acids, hormones and other organic
solutes.
 Translocation occurs through phloem. The
channels of transport are sieve tubes.
 The cytoplasm of one tube cell is
continuous with that of adjacent sieve cells
through sieve plates. The force required for
translocation is produced by companion cells
which lie adjacent to sieve tubes.

Mechanism of phloem transport

 The transport of organic solutes or nutrients occurs through a physical process but entry and exit of
nutrients from the phloem occurs only through an active process which utilises energy from ATP.
 Actively, food materials pass into the phloem from the region of manufacture or storage.
 In the sieve tubes, nutrients being in high concentration exert an osmotic pressure, causes entry of water.
Develops high turgor pressure. Forces nutrients to pass towards the region which has low turgor pressure.
 Low pressure is maintained in the area where soluble food is being withdrawn for consumption or storage by
an active process.

READING OF NCERT TEXTBOOK IS MUST