Title 06-Transportation & Excretion.pdf ✅

TRANSPORTATION & EXCRETION 6 CHAPTER CONTENTS • Transportation & Excretion • Excretion in Plants • Transpiration • Transpiration in Animals • Circulatory system • Constituent of blood. • Removal of waste • Excretion in human ➢ TRANSPORTATION & EXCRETION Plants & animals both required food for; air & water for the maintenance & breeding of a cell. Each has to be supplied to the cell of the body in a right quantity . The transport of material in plants is carried out by the vascular tissue.  Vascular Tissue : There are 2 types of vascular tissues found in plants • Xylem : Xylem transport water & nutrient upwards from the roots to the leave. Evaporation of water from the leaves during transpiration produces a pulling force causing water to move up • Phloem : It carry the food prepared by the leaves during photosynthesis downward to all parts of the plants.  Transportation of water, minerals & food : • The roots have root hairs which increase the surface area of the root for absorption of water & minerals dissolved in water. The root hair come in contact with water present between soil particles. Soil Particle Cell wall Nucleus Vacuole To Stem Cytoplasm Xylem Vessel  Traspiration pulls : • The water move from the root hair to the xylem in the root. The absorbed water then moves up the stem through the xylem by the force developed in the leaves by the transpiration, called transpiration pull.  Ascent of sap : • The fluid containing water & dissolved nutrient is called sap. The movement of sap through the xylem is called ascent of sap  Translocation : • The food is transported from the leaves to other parts of the plant, called translocation.

Left Auricle Left ventricle Septum Pulmonary vein Pulmonary Artery Aorta Superior vena cava Right Auricle Inferior venacava Right ventricle  Blood vessels : • These are blood-filled tubes. • Arteries, veins and capillaries called blood vessels. Met Arteriole Throughfare Channel Precapillary sphincter Venule Venou Capillaries Arterial Capillaries Arteriole Arteries : • Arteries are thick walled blood vessels, making up the arterial system and carrying blood away from the heart. • Smaller arteries are called arterioles. • Arterioles are branched off from arteries. • Except in the pulmonary arteries, the blood contains oxygen. • In all arteries, blood carries dissolved food and waste, brought into the heart by veins and is then transferred to arteries. • Arteries carry the food to the cells and waste to the kidneys. Veins : • Veins are wide, thick walled, blood vessels. • Veins make the venous system and carries blood back to the heart. • Small veins are called venules. • Veins contain valves to stop blood flowing backwards due to gravity and are formed of merging venules • The blood in the veins leading from the digestive system and liver also carries dissolved food. This is transferred to the arteries in the heart Capillaries : • Narrow, thin walled blood vessels branching off arterioles to form a complex network is called capillaries. • Dissolved food and oxygen pass out through the walls of capillaries to the body cells and carbon dioxide and waste pass in • The capillaries of the digestive organs and liver also pick up food • Finally, capillaries join up to form small veins called venules  Blood : • It is a connective tissue in fluid form • An adult human has around 5.5 litres of blood • A red fluid flows in the body • It supplies food and oxygen to every body cell • It removes wastes from the cells • It regulates body temperature • It protects against infection ➢ CONSTITUENT OF BLOOD
 RBC (Red Blood Corpuscles) : • This is also called erythrocytes. • RBC is a red disc shaped cells with no nuclei. • They are made in the bone marrow and contain haemoglobin (an iron compound that gives blood a dark red colour). • RBC combines with oxygen to form oxy- haemoglobin and the blood becomes bright red. • The red cells pass the oxygen to the body cells by the process of diffusion and then returns to the - lungs with haemoglobin.  WBC (White Blood Corpuscles) : • This is also called leucocytes. • WBC is large, opaque blood cells, which helps in body defence. • WBC makes antibodies. Antibodies produce antigens, which combat against any bacterial or viral infection. Antigens are mostly protein.  Plasma : • It is a pale liquid with 90% water in it. • Plasma contains the blood cells. • Plasma carries dissolved food for the body cells, waste matter, and carbon dioxide secreted by them.  Platelets : • It is also called thrombocytes. • It is a very small, disc shaped bodies with no nuclei. • It is made in the bone marrow. • They gather particularly in an injured area, where they are important in clotting the blood. ➢ REMOVAL OF WASTE The process of removing waste from the body is called excretion Several organs of body is involved in the process of excretion – • The waste generated in the process of digestion is expelled from the large intestine through anus. • Carbon dioxide produced in the process of respiration is expelled from the lungs through the nostrils. ➢ EXCRETION IN HUMANS Chemical waste like urea are excreted by urinary system & skin.The excretory system in human beings consists of the following organs: - A pair of kidneys - A pair of ureters - The urinary bladder - Urethra  Urinary system or Excretory system : Renal Artery Precapillary sphincter Ureter Urinary Bladder Urethra Vena cava Aorta Renal vein • Kidneys : In our body there is a pair of kidneys located in the abdomen, one each on either side of the vertebral column. Each kidney is brick red in colour and bean-shaped. It weighs about 150 g and is about 12 cm in length, 6 cm in width and 3 cm in thickness • Uterers :