Chapter 11 Transportation in Animals and Plants

Column I                           Column II
(i) Stomata                       (b) Transpiration
(ii) Xylem                          (d) Transport of water
(iii) Root hairs                   (a) Absorption of water
(iv) Phloem                       (c) Transport of food

1. Stomata: Stomata are the specialized epidermal structures consists of small pores (surrounded by guard cells) which are responsible for the gaseous exchange between plant and the environment. Transpiration is the loss of water from the aerial parts of the plants like leaves in the water vapours form; and this occurs through the stomata which is known as stomatal transpiration. 

2. Xylem: The water and minerals from soil enters the plant through the roots and then pass into the xylem, then from this the dissolved mineral and water moves in the upward direction that occurs from the soil to the uppermost leaves. This upward movement of minerals and water against the gravitational force through the xylem is known as ascent of sap.

3. Root hair: Roots are the primary source for the absorption of water and contains large number of root hair which makes intimate contact with the soil particles and amplifies the surface area for the water absorption by the plant; then water from the soil enters into the root through root hair. Diagram:

4. Phloem: The movement of the phloem sap (complex mixture of organic and inorganic substances) from the leaves to other parts of the plant through the phloem is known as phloem translocation.

(i) Arteries                                                                                                                                                                                                                                           Arteries have a thick, elastic layer to allow stretching and absorb pressure; it maintains the pressure in the circulatory system. The blood from the heart is transported to all parts of the body by the arteries and the arterioles. The arteries are the blood vessels that carry oxygenated blood from the heart to the tissues of the body through the capillaries.  

(ii) Red blood                                                                                                                                                                                                                                    Red blood cells are red in colour due to the presence of red pigment which is known as haemoglobin. Red blood cells carries oxygen from the lungs to all the cells of the body.                                                                                                                                                                                                                 

(iii) Capillaries                                                                                                                                                                                                                                  Capillaries are the extremely narrow blood vessels (less than 1mm long) which connect arteries to veins and are present in all regions of the body. Capillaries are also known as ‘blood capillaries. Usually blood passes from the heart in the sequence through arteries, arterioles, capillaries, venules and veins and then get back to the heart. 

(iv) Heartbeat                                                                                                                                                                                                                                  The spontaneous rhythmic contraction and relaxation of the heart to pump out and receive the blood to and from the body and completes one cycle of it, is called a heartbeat. The heart beats about 72 times in a minute that can be counted easily by counting the pulses. 

(v) Urea                                                                                                                                                                                                                                          Urea is a major waste product that is produced in our body. It is excreted through the urine is the major function of the kidney. 

(vi) Salts                                                                                                                                                                                                                                             Sweat contains water and salts, and a little of urea and which is removed from the body by sweat glands through the skin. 

(vii) Urine                                                                                                                                                                                                                                           The urea and other unwanted salts dissolve in water in the body to form a yellowish liquid waste of which excretion is important; called urine. For the production of urine, nephrons and collecting ducts performs three processes: glomerular filteration, tubular reabsorption and tubular secretion.

(viii) Transpiration                                                                                                                                                                                                                Transpiration is the loss of water from the aerial parts of the plants like leaves in the water vapours form; and this occurs through the stomata, cuticle or lenticels of the plants which is known as stomatal, cuticle and lenticels transpiration respectively. 

(a); (i) Xylem
The water and minerals from soil enters the plant through the roots and then pass into the xylem, then from this the dissolved mineral and water moves in the upward direction that occurs from the soil to the uppermost leaves. This upward movement of minerals and water against the gravitational force through the xylem is known as ascent of sap. Xylem tissue consists of living and non-living cells; and non- living cells consists of tracheary elements: tracheids and vessel elements.

(b); (iii) Under the fan
Water absorption occurs through the roots can be enhanced by keeping the plants under the fan because of the transpiration process is boosted. Higher vapour pressure differences between leaf air spaces and the external air increases the transpiration rate.

Transport in organism like plants and animals is very necessary as it absorbs all essential components and transport them to all parts of the body. The water and minerals from soil enters the plant through the roots and then pass into the xylem that is from the soil to the uppermost leaves. This upward movement of minerals and water against the gravitational force through the xylem is known as ascent of sap in the plants. Transport of materials is necessary in both plants and animals because every cell needs a regular supply of mineral nutrients.

The uptake of inorganic nutrients from the soil is mineral nutrition which is very important to complete their growth and life cycle and in animals; the food that we eat is broken down into smaller components that is absorbed by the cells. The oxygen that we intake is also transported to all the cells of the body. Our body also requires the removal of waste materials such as carbon dioxide in the breathing process. For the transport of food, oxygen and wastes; our body has a specialised transport system. Similarly, in plants, the transport of water and food is accomplished with the help of xylem and phloem.

Platelets are pale yellow in colour and are also called thrombocytes; are the tiny fragments of megakaryocyte cells in which cytoplasm remains enclosed by the piece of plasma membrane but lacks nuclei. Thrombopoietin hormone is produced by the liver which increases the number of megakaryocytes in the bone marrow and which automatically stimulates platelets production. Platelets are mainly involved in blood clotting (transformation of blood from liquid into solid gel).

They helps to stop blood loss from the damaged blood vessels by forming platelet plus (thin layer). Their granules contains chemical when they released, they promote blood clotting. And, when they bind to clot and prevents from blood loss. Thus, if there are no platelets in the blood, there will be excessive loss of blood during the injury.  

Stomata are the specialized epidermal structures consists of small pores (surrounded by guard cells) which are responsible for the gaseous exchange between plant and the environment. Transpiration is the loss of water from the aerial parts of the plants like leaves in the water vapours form; and this occurs through the stomata which is known as stomatal transpiration. 

FUNCTIONS OF STOMATA:

1. Stomatal opening and closing helps in the gaseous exchange between the plant’s internal tissue and the atmosphere.                                                            2. It helps in transpiration (loss of water); excess water in the form of water vapour.                                                                                                                     3. Stomatal closure at night prevents from water loss, from escaping through pores because at night plants respires like animals.                                               4. It maintains the moisture balance according to weather.                                                                                                                                                            5. Stomata facilitate gaseous exchange as carbon dioxide uptake and release of oxygen during the process of photosynthesis.

The process of Transpiration is the loss of water from leaves that serves very useful function in the plants because it generates s ‘suction force’ in xylem which can pull water from the roots up to great height in the tall trees which is known as ascent of sap.

Another function of transpiration is that it keeps the plant cool in higher temperature by the evaporation. The rate of transpiration increase in moving air because this carries away water vapour from leaves as fast as it comes out of stomata. Higher vapour pressure differences between leaf air spaces and the external air increases the transpiration rate. And, when the rate of transpiration increases, the rate of absorption of water through the roots also get increased. Thus, by keeping a plant under the fan, water absorption through roots can be increased.

The average adult person has about 4 to 6 litres of blood and the study of blood is known as haematology. Four component of blood are as follows:

1. PLASMA: Plasma is pale yellow in colour, slightly alkaline and viscous fluid. It has fixed chemical composition: 90% water and 1% inorganic salts; and inorganic salts and 7 to 8% proteins. The remaining 1- 2% of the plasma is formed by food materials and waste products, dissolved gases, regulatory substances, anticoagulants cholesterol and the antibodies.

2. RED BLOOD CELLS (RBC): Red blood cells are red in colour due to the presence of a red, oxygen carrying pigment called haemoglobin; in the cytoplasm and are most abundant cells in the human body. Their shape varies in different vertebrate classes. In some like fishes, amphibians, reptiles, they are oval, biconvex and nucleated. In mammals, they are circular, biconcave, de-nucleated discs etc.  

3. WHITE BLOOD CELLS (WBC): The white blood cells are also known as leucocytes; it fights from the infection and protect us from diseases that may occurs from the pathogens. White blood cells make chemicals ‘antibodies’ which usually fights against infection. They lack haemoglobin and are rounded irregular shaped cells which changes their shape and capable of doing amoeboid movement.

4. PLATELETS: Platelets are pale yellow in colour and are also called thrombocytes; are the tiny fragments of megakaryocyte cells in which cytoplasm remains enclosed by the piece of plasma membrane but lacks nuclei. Thrombopoietin hormone is produced by the liver which increases the number of megakaryocytes in the bone marrow and which automatically stimulates platelets production. Platelets are mainly involved in blood clotting (transformation of blood from liquid into solid gel). They helps to stop blood loss from the damaged blood vessels by forming platelet plus (thin layer). Their granules contains chemical when they released which promotes blood clotting.

Blood is needed by all the parts of our body because it performs the following important functions in our body and also known as the ‘river of life’:

1. Blood helps in the transportation of food by the plasma from the alimentary canal and liver to all the parts of the body for growth, repair and energy.

2. Blood carries water to all the parts of the body and water balance regulation occurs which is important in the metabolic processes.

3. Blood component; RBCs carries oxygen bound to haemoglobin as the oxyhaemoglobin from the lungs to the tissues for oxidation of food to release energy.

4. Blood component plasma; collects the carbon dioxide from the body tissues and carries it to the lungs for breathing out from the body.

5. Blood component plasma; carries a waste product such as urea, uric acid and creatinine from the liver and other tissues to the kidneys for excretion in urine.

6. Blood protects the body from diseases because it contains white blood cells that kills bacteria and other germs. They act as the soldiers, scavengers and builders of the body.

7. Blood helps in the regulation of body temperature.

Blood is opaque, mobile fluid connective tissue, sticky and slightly heavier than water circulates in our body. Blood is bright red in colour when oxygenated and purple in colour when deoxygenated; and is red in colour because it contains a red pigment called haemoglobin. Red blood cells are red in colour due to the presence of a red, oxygen carrying pigment called haemoglobin; in the cytoplasm and are most abundant cells in the human body. They bound to haemoglobin as the oxyhaemoglobin. The average adult person has about 4 to 6 litres of blood and the study of blood is known as haematology. If there is any deficiency of haemoglobin in the blood of a person then it becomes difficult to provide oxygen to all the cells of body.

HEART: The heart is an organ which pumps blood to all the parts of our body through a network of tubes called blood vessels. Heart beats continuously to circulate blood in the body. The heart works like a pump non-stop throughout our life. It is located in the chest cavity slightly towards the left side. The heart lies between the two lungs and above the diaphragm and its size is roughly equal to our fist. The heart is made up of special muscle called ‘cardiac muscle’ but it is not solid muscle. The heart is hollow inside. The heart has four compartments called ‘chambers’. The upper two chambers of heart are called atria (singular of atria is atrium) and the lower two chambers of heart are called ventricles. On the left side of the heart are left atrium and left atrium and left ventricle. On the right side of the heart are right atrium and right ventricle. Right atrium receives carbon dioxide rich blood from the body. Blood from right atrium enters the right ventricle, which contracts and pumps the blood to the lungs. On the other hand, oxygen rich blood from the lungs returns to the left atrium. From the left atrium, blood enters left ventricles. Left ventricles contracts and pumps the blood to all parts of the body.

Human heart diagram:

Functions of heart: The main functions of heart-
1. Pumping oxygenated blood to the other body parts.
2. Pumping hormones and other vital substances to different parts of the body.
3. Receiving deoxygenated blood and carrying metabolic waste products from the body and pumping it to the lungs for oxygenation.
4. Maintaining blood pressure.

We eat food, drink water for the energy and breathe in air. When our body uses food, water and air, it produces some unwanted substances which are known as waste materials. These waste materials are very toxic for our body. The waste materials must be excreted out from the body so that a person may stay healthy. The removal of waste materials that is produced in the cells of the organisms is called excretion. The various waste materials produced in the cells of the human body are: Carbon dioxide, Urea, Urine and Sweat etc. that has to be excreted out on time. The human body has many organs for the removal of nitrogenous wastes from the body like lungs (for the removal of excess of CO₂), Kidneys (for removal of urea, urine etc.) and Sweat glands (for the removal of sweat) etc.

Yes, it is necessary to remove the waste material from the body to stay healthy.

The excretory system of human beings consists of the following organs that are: two kidneys, two ureters, a bladder and a urethra. The kidneys are bean-shaped organs which are present towards the back of our body just above the waist. The decomposition of unused food proteins in the liver produces urea as waste. This function of kidneys is to filter the blood to remove urea or we can say the excretion of nitrogenous waste from the body occurs by the kidneys.

Each kidney contains numerous tiny filters called ‘nephrons’. When the blood containing urea and other waste salts they passes through the nephrons in the kidneys then these nephrons filters the blood and remove urea and other unwanted inorganic salts from it. The liquid left in the kidneys is yellowish liquid called ‘urine’ which contains urea, other waste salts and excess water which is formed in kidneys, goes into the bladder through the tubes called ureters. Urine is stored in the bladder and is also called ‘urinary bladder’. The urine collected in bladder is passed out from the body at regular intervals through the opening at the end of a tube which is called urethra. Urine is yellowish liquid which consists of 2.5 percent urea, 2.5 percent other waste inorganic salts and 95% of water. An adult human being normally passes out 1 to 1.8 litres of urine per day (24 hours).

                                        Human excretory system