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• Transportation: The movement of substances from one place to another in the body of the organism is called transportation.
• Component of blood – blood contains plasma and red blood cells, white blood cells, platelets. Plasma is made of salt, gases and water.
• Circulatory system
  • Arteries carry blood from heart to other body parts, they are thick and elastic as the pressure inside them is high
  • Veins bring the blood from body parts back to the heart. Veins are thin walled and pressure inside them in low
  • Arteries get branches to form smaller capillaries which again joins to form veins. The exchange of material between the blood and individual cell takes place across the thin walls of capillaries.
  • From the walls of the capillaries some amount of water, proteins escape into the intercellular spaces of the tissues. It is called tissue fluid and is colorless in nature. It is collected in lymphatic capillaries and thus called as lymph
• Structure of human heart
  • Heart is the muscular organ weighing 360 gm.
  • Right and left part of heart is separated to prevent mixing of oxygenated blood into deoxygenated blood.
  • Left and right parts are divided into 4 chambers. Upper two chambers are atrium and lower two chambers are ventricles
• Circulation in humans
  • Initially left and right artium are relaxed
  • Deoxygenated blood enters into right atrium through vena cava. Simultaneously left artium receives oxygenated blood from pulmonary veins
  • The atria contracts and ventricles expand. Blood from atria get pushed to respective ventricles. Thus left ventricle get filled with oxygenated blood and right ventricle get filled with deoxygenated blood.
  • ventricles contract so the oxygenated blood from left ventricles pumped out to body organs through the largest artery called as aorta. Simultaneously the deoxygenated blood from right ventricles is pumped out to lungs for oxygenation through pulmonary artery.
  • Valves present at the junction of atrium and ventricles prevent Backflow of Blood.
  • The blood from the lungs after oxygenation, enter into left atrium and deoxygenated blood enter in right atrium. Since blood enter twice in heart hence the circulation is called Double Circulation.
• Excretion – process of eliminating the harmful substances outside the body is called as excretion.
• Excretion in humans
  • Excretory system in human being includes pair of kidneys, pair of ureters, urinary bladder and urethra.
  • Kidneys are bean shaped structures located at the back of the abdomen
  • Nephron: The basic unit for filtering in the kidney is nephron. It is a cluster of thin walled blood capillaries.
  • Bowman’s capsule: Nephron consists of cup shaped thin walled upper end called Bowman’s capsule.
  • Glomerulus: The bundle of blood capillaries present in Bowman’s capsule is called glomerulus.
  • Functioning of kidneys –
    • Blood containing harmful products enter into glomerulus of nephron
    • In bowmans capsule, water molecules and small molecules of other substances to pass through the wall, thus blood gets separated from other molecules
    • Filtered blood is taken back to heart by renal vein
    • The filtrate passes through tubular structure of nephron where water and useful molecules are reabsorbed.
    • The remaining fluid containing waste is called urine enters in long tube called ureter
    • Urine is stored in urinary bladder from where it is thrown outside the body through urethra
• Excretion by skin and lungs – Skin eliminates waste products in the form of sweat and lungs filters blood so as to eliminates harmful gases like carbon dioxide
• Transportation in plants
  • Transportation of water – Xylem is a special tissue that carries water and minerals from roots to upper body parts. Root pressure allows water to get pushed in upward direction, however it works well for short plants not for the tall plants. Transpiration pull is another way by which water gets transported in plants. Due to transpiration suction is created in the xylem vessels and water moves in the upward direction.
  • Transportation of food – Phloem allow the movement of food material in the plants. Movement of food into other parts of the plants is called translocation.Due to active transport the concentration of water inside the phloem cell decreases thus water from Xylem move into the phloem cell by the process of Osmosis. Which increases the concentration of water inside the phloem cell than adjacent phloem cell. Increased concentration causes the cell to exert high pressure on their walls. Due to which the food materials move to adjacent cells that have low pressure. In this way the food materials are transported according to plant needs through the phloem tissue.