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Excretion - Kidneys- Nephron-Human excretory system

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                             EXCRETION Excretion is the elimination of wastes produced by the body. Excretory systems regulate the chemical composition of body fluids by removing metabolic wastes and retaining the proper amounts of water, salts, and nutrients.Components of this system in vertebrates include the, liver,lungs,kidneys,and skin. Liver:   The liver breaks down excess amino acids and produces urea. Liver breakdowns hemoglobin into bilirubin. is excreted with the bile into the intestine and expelled with the faeces. Lungs: The lungs supply the body with  oxygen, but they are also excretory organs because they get rid of carbon dioxide. Kidneys: The kidneys remove urea and other nitrogenous waste from the blood. They also expel  excess water, salts,hormones and drugs. Skin: skin is the larges organ of the body. Sweat consists of water, with sodium chloride and traces of urea dissolved in i...

Neurons-Reflex action and Reflex arc-Types of Neurons-Motor neurons-Sensory neurons-Effectors-Receptors

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Neurons: The central Nervous system (which includes the brain and the spinal cord) is made up of cells called Neurons.Neurons are designed to transmit information to other nerve cells,muscles, or glands cells.Neurons send message in the form of nerve impulse. Nerve impulses are electrical signals that travel along a neuron.It is responsible for communication between different types of neurons and to give orders to effectors. Speed of nerve impulse is about 100m/s. Parts of Neurons: --------------------------------------------------------------------------------------- Cell Body : The cell body has a nucleus and most of the organelles of the cell. Dendrites:   The small extensions of the cell body are called dendrites.They receive messages from other cell and conduct them towards the cell body. Axon:        Axon is also called the nerve fibre. It is a portion of a neuron that carries nerve impulses away from the cell body/ The axon receive message from the c...

Nervous System-Brain and Spinal cord -All Information-Human Organ System

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 Human Organ System:   Human organ system cooperate and work together to maintain life. eg: Excretory  system, Respiratory system, Digestive system, Circulatory system and Nervous system.  Nervous system controls and coordinates all other system of the body. Excretory system regulates the chemical composition of body fluids by removing wastes.                                                                                           Introduction to Nervous System:                                                What is a nervous system? Do we sleep every day?  Yes, we do, unless we have an important event or   ...