The Urinary System

Front

Excretion Noun

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[ek-skree-shun]

Back

Excretion

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The process of removing organic metabolic wastes, such as urea, from the body's fluids to maintain internal balance.

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Example: This diagram shows the urinary system, where kidneys filter waste from the blood to create urine, which is then expelled from the body.

Front

Kidney Noun

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[kid-nee]

Back

Kidney

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A pair of bean-shaped organs that filter toxins from the blood and convert waste products into urine.

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Example: This diagram shows a cross-section of the kidney, labeling its main parts and its connection to blood vessels (renal artery/vein) and the ureter.

Front

Nephron Noun

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[nef-ron]

Back

Nephron

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The microscopic structural and functional unit of the kidney, responsible for filtering blood and forming urine.

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Example: This diagram shows a nephron, the tiny filtering unit inside a kidney. It illustrates how blood with waste is filtered to create urine.

Front

Glomerulus Noun

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[glo-mer-yoo-lus]

Back

Glomerulus

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A small, tangled cluster of capillaries located within a nephron where the initial filtration of blood takes place.

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Example: This diagram shows the glomerulus, a tangle of capillaries within the nephron, where waste is filtered from the blood to start making urine.

Front

Filtration Noun

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[fil-tray-shun]

Back

Filtration

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The first step in urine formation where high pressure forces water and solutes from blood in the glomerulus.

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Example: This diagram shows the kidney filtering blood. Unfiltered blood enters, waste is removed to form urine, and clean, filtered blood exits.

Front

Reabsorption Noun

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[ree-ab-sorp-shun]

Back

Reabsorption

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The process where the nephron removes water and useful solutes from the tubular fluid and returns them to blood.

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Example: This diagram shows reabsorption (arrow 2) where useful substances are moved from the kidney tubule back into the surrounding blood vessels to be kept by the body.

Front

Secretion Noun

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[si-kree-shun]

Back

Secretion

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The transfer of waste materials, such as hydrogen ions and drugs, from the blood into the kidney tubules.

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Example: This diagram shows secretion as the process where waste products move from the blood directly into the pre-urine, to be removed from the body.

Front

Ureter Noun

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[yur-i-ter]

Back

Ureter

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One of two narrow tubes that carry urine from the kidneys to the urinary bladder through muscular contractions.

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Example: This diagram shows the ureters as tubes that carry urine from the kidneys down to the bladder, placing them within the urinary system.

Front

Urinary Bladder Noun

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[yur-i-ner-ee blad-er]

Back

Urinary Bladder

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A hollow, muscular, and distensible organ that sits on the pelvic floor and stores urine from the kidneys.

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Example: This diagram shows the urinary bladder's location in the body, connected to the kidneys by ureters and leading to the urethra for urination.

Front

Urethra Noun

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[yoo-ree-thruh]

Back

Urethra

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The tube through which urine passes from the bladder to the exterior of the body during urination.

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Example: This diagram shows the urethra as the tube that carries urine from the bladder out of the body, placing it within the context of the urinary system.