TRANSPORTATION OF MATERIALS, Std- 10

Transportation :-
The distribution of materials like food and oxygen to all parts of the body as well as the removal of body wastes is called transportation.
➞ It is performed by a set of organs known as transport system.
* Transportation of materials in plants
➞ Transportation of materials in plants occurs through specialized conducting tissues which are

(i) Xylem &
(ii) Phloem
Xylem
➞ It is a conducting tissue in plants which conducts water and Minerals from root to the leaves.
➞ It shows unidirectional movement.
Phloem
➞ It is also a conducting tissue which conducts food materials from leaves to the other part of the

plants.
➞ It shows multi directional movement.

Transportation of materials and fluids in Human beings
➤ Human beings have a specialized system which transport materials and fluids known as circulatory system.

➞ It consist of:-
(i) Circulatory medium - blood tissue fluid and lymph.
(ii) Blood vessels - arteries, veins and capillaries.
(iii) Pumping organ - heart
Blood
➞ It is found in the heart and blood vessels like arteries veins and capillaries.
➞ It is a connective tissue.
➞ An average human being has about 5.5 litres of blood in his body.
➞ It carries oxygen,digested food,hormones and enzymes to all parts of the body.
➞ It is red in colour and salty in taste.
➞ It is made up of two components:-
(i) Plasma -> 50 - 60 %
(ii) Cellular Elements -> 40 - 50 %

Plasma
➞ It is a straw coloured aqua solution.
➞ It contains :-

(i) Water - 90 to 92%
(ii) Inorganic Salts - 1 to 2% &
(iii) Organic compounds - 7 to 8%
Note:- Inorganic Salts are Chlorides, Carbonates ,Bicarbonates, Sulphates, and
Phosphates of Sodium, Potassium, Calcium etc.
                    Cellular elements
➤Three Types of cellular elements are found in human blood.
1. Red blood corpuscles or RBCs
2. White blood corpuscles or WBCs
3. Platelets

             Red Blood corpuscles( RBCs )
➞ It is also known as erythrocytes.
➞ It is enucleated disc like structure and very small in size.
➞ It is produced in the red bone marrow of bones and the average lifespan is about 100 - 120 days.
➝ It is red in colour due to presence of a pigment that is known as haemoglobin.

Note:- The old and worn out RBCs are destroyed in the spleen and liver.
➥ Spleen - Blood bank of the body.

White Blood Corpuscles ( WBCs )

➞It is also known as leukocytes and soldiers of the body.
➞ Cells are rounded to irregular shaped and capable of Amoeboid movement.
➞ It is colourless liquid due to lack of haemoglobin.

➞ Its life span is about 13 - 20 days.
➞ It is of two types:-
1. Granulocytes (Contain granules in their cytoplasm )
➝ It is also of three types .
!- Neutrophils
!!- Basophils
!!!- Eosinophils.

2. Agranulocytes ( lacking granules in their cytoplasm).
➝ It is also of 2 types:-
! - lymphocytes and
!! - Monocytes
➞ WBCs help in engulfing solid substances like bacteria and other microbes.
➞ It is responsible for immunity and helps in the formation of antibodies .

Blood Platelets
➞ They are colourless oval or round cells.

➞ It plays an important role in blood clotting.
➞ It is also enucleated.
➞ It releases a chemical thromboplastin which initiates the process of clotting of blood
in a cut or wound.

Functions of Blood

➧ Some important functions of blood are :-
1.Transports nutrients, respiratory gases, waste products.
2. Transports body secretions and regulates body temperature.