Digestive & Urinary System (Location Of Absorption of Each …
Digestive & Urinary System
Digestive and Urinary Systems
also known as the renal system or urinary tract, consists of the kidneys, ureters, bladder, and the urethra. The purpose of the urinary system is to eliminate waste from the body, regulate blood volume and blood pressure, control levels of electrolytes and metabolites, and regulate blood pH.
To achieve the goal of providing energy and nutrients to the body, six major functions take place in the digestive system: Ingestion. Secretion. Mixing and movement.
Major Organs of Digestive and Urinary Systems
is the first portion of the alimentary canal that receives food and produces saliva. The oral mucosa is the mucous membrane epithelium lining the inside of the mouth.
is the part of the throat behind the mouth and nasal cavity and above the esophagus and larynx, or the tubes going down to the stomach and the lungs.
a muscular tube connecting the throat (pharynx) with the stomach. The esophagus is about 8 inches long, and is lined by moist pink tissue called mucosa. The esophagus runs behind the windpipe (trachea) and heart, and in front of the spine.
a muscular organ located on the left side of the upper abdomen. The stomach receives food from the esophagus. As food reaches the end of the esophagus, it enters the stomach through a muscular valve called the lower esophageal sphincter. The stomach secretes acid and enzymes that digest food.
is the part of the gastrointestinal tract between the stomach and the large intestine, and is where most of the end absorption of food takes place. The small intestine has three distinct regions – the duodenum, jejunum, and ileum.
is the last part of the gastrointestinal tract and of the digestive system in vertebrates. Water is absorbed here and the remaining waste material is stored as feces before being removed by defecation.
the opening at the end of the alimentary canal through which solid waste matter leaves the body
are the hardest substances in the human body. Besides being essential for chewing, the teeth play an important role in speech. Parts of the teeth include: • Enamel: The hardest, white outer part of the tooth.
mammals are exocrine glands that produce saliva through a system of ducts. Humans have three paired major salivary glands (parotid, submandibular, and sublingual) as well as hundreds of minor salivary glands. Salivary glands can be classified as serous, mucous or seromucous (mixed).
are located in different regions of the stomach. These are the fundic glands, the cardiac glands, and the pyloric glands. The glands and gastric pits are located in the stomach lining
is a gland found in between villi in the intestinal epithelium lining of the small intestine and large intestine (colon).
is a large, meaty organ that sits on the right side of the belly. ... The liver also detoxifies chemicals and metabolizes drugs. As it does so, the liver secretes bile that ends up back in the intestines. The liver also makes proteins important for blood clotting and other functions.
a small pouch that sits just under the liver. The gallbladder stores bile produced by the liver. After meals, the gallbladder is empty and flat, like a deflated balloon. Before a meal, the gallbladder may be full of bile and about the size of a small pear.
a large vein carrying deoxygenated blood into the heart.
normally arise off the left interior side of the abdominal aorta, immediately below the superior mesenteric artery, and supply the kidneys with blood.
are a pair of bean-shaped organs on either side of your spine, below your ribs and behind your belly. Each kidney is about 4 or 5 inches long, roughly the size of a large fist. The kidneys' job is to filter your blood.
is a muscular sac in the pelvis, just above and behind the pubic bone. When empty, the bladder is about the size and shape of a pear. Urine is made in the kidneys and travels down two tubes called ureters to the bladder. The bladder stores urine, allowing urination to be infrequent and controlled.
begins at the top of the left ventricle, the heart's muscular pumping chamber. The heart pumps blood from the left ventricle into the aorta through the aortic valve.
are veins that drain the kidney. They connect the kidney to the inferior vena cava. They carry the blood filtered by the kidney.
the duct by which urine passes from the kidney to the bladder or cloaca.
the duct by which urine is conveyed out of the body from the bladder, and which in male vertebrates also conveys semen.
are substances produced by our bodies that help us to digest the foods we eat. These enzymes are secreted by the various parts of our digestive system and they help to break down food components such as proteins, carbohydrates, and fats.
Lipase takes the fat and triglycerides you eat and converts them into essential fatty acids, used for an abundance of functions in the body
Lactase targets lactose (a sugar found in dairy products) and converts it into other types of sugars – namely glucose and galactose.
Amylase converts carbohydrates and starches into sugars for energy
Location Of Digestion of Each
Large food molecules (for example, proteins, lipids, nucleic acids, and starches) must be broken down into subunits that are small enough to be absorbed by the lining of the alimentary canal. This is accomplished by enzymes through hydrolysis.
In the small intestine, pancreatic amylase does the ‘heavy lifting’ for starch and carbohydrate digestion. After amylases break down starch into smaller fragments, the brush border enzyme α-dextrinase starts working on α-dextrin, breaking off one glucose unit at a time. Three brush border enzymes hydrolyze sucrose, lactose, and maltose into monosaccharides. Sucrase splits sucrose into one molecule of fructose and one molecule of glucose; maltase breaks down maltose and maltotriose into two and three glucose molecules, respectively; and lactase breaks down lactose into one molecule of glucose and one molecule of galactose. Insufficient lactase can lead to lactose intolerance.
The three lipases responsible for lipid digestion are lingual lipase, gastric lipase, and pancreatic lipase. However, because the pancreas is the only consequential source of lipase, virtually all lipid digestion occurs in the small intestine. Pancreatic lipase breaks down each triglyceride into two free fatty acids and a monoglyceride. The fatty acids include both short-chain (less than 10 to 12 carbons) and long-chain fatty acids.
The digestion of protein starts in the stomach, where HCl and pepsin break proteins into smaller polypeptides, which then travel to the small intestine. Chemical digestion in the small intestine is continued by pancreatic enzymes, including chymotrypsin and trypsin, each of which act on specific bonds in amino acid sequences. At the same time, the cells of the brush border secrete enzymes such as aminopeptidase and dipeptidase, which further break down peptide chains. This results in molecules small enough to enter the bloodstream.
Nucleic Acid Digestion
Two types of pancreatic nuclease are responsible for their digestion: deoxyribonuclease, which digests DNA, and ribonuclease, which digests RNA. The nucleotides produced by this digestion are further broken down by two intestinal brush border enzymes (nucleosidase and phosphatase) into pentoses, phosphates, and nitrogenous bases, which can be absorbed through the alimentary canal wall.
Layers of The GI Tract
The GI tract contains four layers: the innermost layer is the mucosa, underneath this is the submucosa, followed by the muscularis propria and finally, the outermost layer - the adventitia. The structure of these layers varies, in different regions of the digestive system, depending on their function.
Nephron Anatomy and Physiology
The nephron of the kidney is made up of two major parts; the renal corpuscle and the tubules. These are then both sub-divided into various parts and overall it is this structure which allows the kidney to filter the blood and then alter the composition of this filtrate to ensure that waste products are excreted and useful compounds preserved.
The renal corpuscle can be subdivided into the glomerulus and the bowmans capsule
The tubules are split into the proximal tubule, the loop of henle, the distal tubule and the collecting ducts.
Disorders of The Digestive and Urinary Systems
Many symptoms can signal problems with the GI tract, including: abdominal pain, blood in the stool, bloating, constipation, diarrhea, heartburn, incontinence, nausea and vomiting and difficulty swallowing, according to the NIH.
widely known diseases of the digestive system is colon cancer. According to the Centers for Disease Control (CDC), Excluding skin cancers, colon and rectal cancer, or colorectal cancer
Urinary tract infections (UTIs) occur when bacteria enter the urinary tract; they can affect the urethra, bladder or even the kidneys.
Interstitial Cystitis also called painful bladder syndrome, is a chronic bladder condition, primarily in women, that causes bladder pressure and pain and, sometimes, pelvic pain to varying degrees, according to the Mayo Clinic. It can cause bladder scarring, and can make the bladder less elastic. While the cause isn't known, many people with the condition also have a defect in their epithelium, the protective lining of the bladder.
Kidney stones are clumps of calcium oxalate that can be found anywhere in the urinary tract. Kidney stones form when chemicals in the urine become concentrated enough to form a solid mass, according to the Cleveland Clinic.
Bladder cancer is diagnosed in about 75,000 Americans each year and is more frequent in men and the elderly according. It is predicted that 81,190 new cases of bladder cancer (about 62,380 in men and 18,810 in women) and bout 17,240 deaths from bladder cancer (about 12,520 in men and 4,720 in women) will occur in 2018, according to American Cancer Society. The symptoms, including back or pelvic pain, difficulty urinating and urgent/and or frequent urination, mimic other diseases or disorders of the urinary system.
Location Of Absorption of Each
The mechanical and digestive processes have one goal: to convert food into molecules small enough to be absorbed by the epithelial cells of the intestinal villi.
The small intestine is highly efficient at this, absorbing monosaccharides at an estimated rate of 120 grams per hour. All normally digested dietary carbohydrates are absorbed; indigestible fibers are eliminated in the feces.
Almost all (95 to 98 percent) protein is digested and absorbed in the small intestine. The type of carrier that transports an amino acid varies. Most carriers are linked to the active transport of sodium.
About 95 percent of lipids are absorbed in the small intestine. Bile salts not only speed up lipid digestion, they are also essential to the absorption of the end products of lipid digestion.
Nucleic Acid Absorption
The products of nucleic acid digestion—pentose sugars, nitrogenous bases, and phosphate ions—are transported by carriers across the villus epithelium via active transport. These products then enter the bloodstream.
The electrolytes absorbed by the small intestine are from both GI secretions and ingested foods. Since electrolytes dissociate into ions in water, most are absorbed via active transport throughout the entire small intestine. During absorption, co-transport mechanisms result in the accumulation of sodium ions inside the cells, whereas anti-port mechanisms reduce the potassium ion concentration inside the cells. To restore the sodium-potassium gradient across the cell membrane, a sodium-potassium pump requiring ATP pumps sodium out and potassium in.
The small intestine absorbs the vitamins that occur naturally in food and supplements. Fat-soluble vitamins (A, D, E, and K) are absorbed along with dietary lipids in micelles via simple diffusion.
About 90 percent of this water is absorbed in the small intestine. Water absorption is driven by the concentration gradient of the water: The concentration of water is higher in chyme than it is in epithelial cells. Thus, water moves down its concentration gradient from the chyme into cells. As noted earlier, much of the remaining water is then absorbed in the colon.