The Digestive & Urinary System: By Carolina Alvarado Period 5 Honors Anatomy
Major functions of the digestive system
The function of the digestive system is digestion and absorption. Digestion is the breakdown of food into small molecules, which are then absorbed into the body.
Nephron anatomy and physiology
Layers of the GI tract
The GI tract is a series of hollow organs joined in a long, twisting tube from the mouth to the anus. The hollow organs that make up the GI tract are the mouth, esophagus, stomach, small intestine, large intestine, and* anus.
Major functions of the urinary systems
The urinary system's function is to filter blood and create urine as a waste by-product.
Digestive enzymes
Digestion is important because your body needs nutrients from food and drink to work properly and stay healthy
Location of digestion and absorption of each macromolecule
The human body ingests several types of organic macromolecules that are used for nutrition and energy. These macromolecules are carbohydrates, proteins and lipids.
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Major organs of the urinary systems
Nephrons are the “functional units” of the kidney; they cleanse the blood of toxins and balance the constituents of the circulation to homeostatic set points through the processes of filtration, reabsorption, and secretion.
The organs of the urinary system include the kidneys, ureters, bladder and urethra.
Major organs of the digestive system
The liver, pancreas, and gallbladder are the organs of the digestive system.
Propulsion is the movement of food along the digestive tract.
Secretion of digestive enzymes and other substances liquefies and chemically breaks down the food.
Ingestion is the process of eating.
Mechanical digestion is the process of physically breaking down food into smaller pieces.
Chemical digestion is the process of chemically breaking down food into simpler molecules.
The digestive system breaks nutrients into parts small enough for your body to absorb and use for energy, growth, and cell repair.
Proteins, fats, carbohydrates, vitamins NIH external link, minerals NIH external link, and water are nutrients.
Liver. makes a digestive juice called bile that helps digest fats and some vitamins. Bile ducts carry bile from the liver to the gallbladder for storage, or to the small intestine for use.
Gallbladder. stores bile between meals. When you eat, your gallbladder squeezes bile through the bile ducts into the small intestine.
Pancreas. makes a digestive juice that has enzymes that break down carbohydrates, fats, and proteins. The pancreas delivers the digestive juice to the small intestine through small tubes called ducts.
Small intestine. The muscles of the small intestine mix food with digestive juices from the pancreas, liver, and intestine, and push the mixture forward for further digestion. The walls of the small intestine absorb water and the digested nutrients into the bloodstream. As peristalsis continues, the waste products of the digestive process move into the large intestine.
Stomach. After food enters the stomach, the stomach muscles mix the food and liquid with digestive juices. The stomach slowly empties its contents, called chyme, into the small intestine.
Large intestine. Waste products from the digestive process include undigested parts of food, fluid, and older cells from the lining of the GI tract. The large intestine absorbs water and changes the waste from a liquid into a stool. Peristalsis helps move the stool into the rectum.
Esophagus. After swallowing, the process becomes automatic. The brain signals the muscles of the esophagus and peristalsis begins.
Rectum. The lower end of the large intestine, the rectum, stores stool until it pushes stool out of the anus during a bowel movement.
Mouth. Food starts to move through the GI tract when eating and once one swallows, the tongue pushes the food into the throat. A small flap of tissue, called the epiglottis, folds over your windpipe to prevent choking and the food passes into the esophagus.
Urea is produced when foods containing protein, such as meat, poultry, and certain vegetables, are broken down in the body.
Urea is carried in the bloodstream to the kidneys, where it is removed along with water and other wastes in the form of urine.
The kidney and urinary systems help the body to eliminate liquid waste called urea, and to keep chemicals, such as potassium and sodium, and water in balance.
Two ureters. These narrow tubes carry urine from the kidneys to the bladder. Muscles in the ureter walls continually tighten and relax forcing urine downward, away from the kidneys. If urine backs up, or is allowed to stand still, a kidney infection can develop. About every 10 to 15 seconds, small amounts of urine are emptied into the bladder from the ureters.
Bladder. This triangle-shaped, hollow organ is located in the lower abdomen. It is held in place by ligaments that are attached to other organs and the pelvic bones. The bladder's walls relax and expand to store urine, and contract and flatten to empty urine through the urethra. The typical healthy adult bladder can store up to two cups of urine for two to five hours.
Two kidneys. This pair of purplish-brown organs is located below the ribs toward the middle of the back. Their function is to remove waste products and drugs from the body, balance the body's fluids,release hormones to regulate blood pressure, and control production of red blood cells
Urethra. This tube allows urine to pass outside the body. The brain signals the bladder muscles to tighten, which squeezes urine out of the bladder. At the same time, the brain signals the sphincter muscles to relax to let urine exit the bladder through the urethra. When all the signals occur in the correct order, normal urination occurs.
Carbohydrates, also known as polysaccharides or sugars, are water-soluble polymers that consist of individual monomer units held together by glycosidic bonds. Our body only contains enzymes to break alpha-glycosidic linkages. In order to actual absorb these sugars into our cells, our body must digest (break down) these polysaccharides
Proteins are yet another example of a macromolecule that is commonly ingested via food. Proteins are water-soluble polymers that consist of individual units called amino acids held together by peptide bonds. For this reason, proteins are also called polypeptides. Proteins have several stages of structure including primary, secondary, tertiary and quaternary. In order for our cells to actually absorb proteins, our body must first denature the proteins and then break them down into their amino acid form.
The final type of macromolecule that we ingest into our bodies are lipids, also known as fats. Lipids are not water-soluble and are not polymers. They can come in many different forms such as steroids, fatty acids, phospholipids, triglycerides, etc. Each of these types serves its own purpose. Since lipids are not water soluble, they cannot dissolve in our blood and must be carried by special protein carriers.
Each nephron consists of a blood supply and a specialized network of ducts called a tubule.
1.For each nephron, an afferent arteriole feeds a high-pressure capillary bed called the glomerulus. Blood is filtered by the glomerulus to produce a fluid which is caught by the nephron tubule, called filtrate. The proximal end of the tubule that surrounds the glomerulus and catches the filtered fluid is the glomerular (Bowman’s) capsule.
The nephrons also function to control blood pressure (via production of renin), red blood cell production (via the hormone erythropoetin), and calcium absorption (via conversion of calcidiol into calcitriol, the active form of vitamin D).
2.The glomerulus and glomerular capsule together form the renal corpuscle. Filtered fluid caught by the glomerular capsule (filtrate) travels through the rest of the tubule to the proximal convoluted tubule, loop of Henle and distal convoluted tubule, in this order, before exiting the nephron into common collecting ducts shared by many nephrons.
3.Though all nephron glomeruli are in the cortex, some nephrons have short loops of Henle that do not dip far beyond the cortex. These nephrons are called cortical nephrons. About 15 percent of nephrons have very long loops of Henle that extend deep into the medulla and are called juxtamedullary nephrons.
4.The efferent arteriole then forms a second capillary network around the tubule, called the peritubular capillaries. For juxtamedullary nephrons, the portion of the capillary that follows the loop of Henle deep into the medulla is called the vasa recta.
- As the glomerular filtrate progresses through the tubule, these capillary networks recover most of the solutes and water, and return them to the circulation.