Digestive System Mouth Digestion begins in the Chewing
Digestive System
Mouth • Digestion begins in the ____ Chewing begins the process of digestion • _________is the physical Mechanical digestion breakdown of large pieces of food into smaller pieces. Chemical digestion • _________large food molecules are broken down into smaller food molecules with the help of different enzymes.
Mouth salivary glands secrete saliva, which • ________ amylase to break the contains the enzyme _____ starches (which is what type of bonds in _____ macromolecule: _______) and releases Carbohydrate lysozyme sugar. It also contains the enzyme _____ that fights infection by digesting the cell walls of moisten ____ bacteria. The saliva also helps ______ the food and make it easier to chew. The release of saliva is under the control of the nervous system ________
Esophagus tongue and your throat • Your _______ muscles help you swallow your food, which (after swallowing) is bolus. As you swallow, the now called a _______ epiglottis ____ closes over the _______ trachea and the bolus esophagus Gravity enters the ______ is not responsible for food going down into the stomach.
Esophagus smooth • A series of contractions of _______ muscle squeeze the food through the ______. This is called peristalsis _____. esophagus A thick ring of muscle called the cardiac sphincter closes the esophagus _______ and prevents the contents of the ____ stomach from moving back into the esophagus reflux (also known as acid ____). ***Remember: No Digestion_ occurs in the esophagus.
Stomach • Food from the esophagus empties into a large stomach muscular sac called the ______. 3 Alternating contractions of the stomach’s ____ smooth muscle layers churn _____ and mix the food ____.
Stomach- Chemical digestion: • The stomach contains microscopic ________ Gastric glands that produce and release various substances. Some of these include: • ____Mucus a fluid that _____ lubricates and _____ protects the stomach wall. (Hydrochloric Acid) makes the contents of the • HCl ____________stomach very _______, acidic & activates pepsin. • Pepsin ____- an enzyme that begins the digestion of acidic conditions _______ & works best under the _______ proteins amylase , is destroyed in the stomach • One enzyme, _____ acid. This means that due to the high level of ______ digestion of carbohydrates _______ stops until the food reaches the small _________. intestine
Stomach- Mechanical digestion: contract to churn and mix Stomach muscles ____ the food & fluids in the stomach, producing chyme. After some a substance called ______ 1 to __ 2 hours, this new time, usually about __ small intestine through substance enters the ______ the ____ valve. pyloric
Small Intestine • The duodenum _____ is the first part of the small intestine and is where most of the Chemical ______ digestion and absorption _____ of the food you eat occurs here. The small intestine is specialized to absorbnutrients _______. The structure that aids in this absorption are the tiny folded projections villi. These structures increase the called _____ surface area for absorption. Most of the products of _______ carbohydrates and _______ protein digestion are absorbed into _______ the ______ capillaries in the villi.
Small Intestine fat and some _____ • Molecules of undigested ___ fatty acids are absorbed by ____ vessels. By lymph the time food is ready to leave the small intestine, it is basically ____ nutrient - free…. . only celluluose _______, water and other indigestible _____, substances are left. Accessory structures that aid in digestion:
Small Intestine • Pancreas- produces: enzymes that help break down carbohydrates, -_____proteins, lipids, and nucleic acids Sodium bicarbonate a base that neutralizes • -_________stomach acid so these enzymes can be effective bile a fluid loaded with lipids • Liver- produces ____, and other salts. It helps make it easier for fat. Bile is stored in the enzymes to break down ___ Gall bladder ______
Large Intestine Colon When _______ chyme leaves the • Another name is ______. small intestine, it enters the large intestine. The water function of the large intestine is to remove _______ bacteria from undigested material. Colonies of _____ vitamin K and other substances for the produce _____ waste material that body to use. Concentrated _______ water has been removed passes remains after ______ rectum through the _____ and is eliminated from the body.
Ch. 38 Excretory System
Excretory System Functions: of chemical wastes • The elimination ___________from the body is know as excretion excretes carbon • For example; lungs ______ dioxide water _____& the skin excretes _____ salt and ____in sweat. • Therefore, the lungs and skin are part of the excretory system
Excretory System Functions: • The excretory system is a system of organs that waste remove _______from the body. • The mains organ of the excretion are the kidneys _____ • The removal of urea- a substance that is the proteins the body result of ______ metabolism of ____in water in cells- along with the regulation of _______ bloodstream blood p. H the________, maintain______, homeostasis & ______are the principal job of the kidneys
Structure of the kidneys: • Each about the size of the fist _____ • Located on either side of spinal column the _______in the lower back • Blood flows into each kidney through a • renal artery ___________ Blood leaves through a renal vein ________
Structure of the kidneys: ureter • A tube called the_______, leaves each, carrying urine ______to the bladder. urinary bladder • The ________is a saclike organ where urine is stored before being excreted through a tube called the urethra
The 3 parts of the kidneys : Renal cortex- outer part Renal medulla- inner part Renal pelvis- middle part
The main functional unit of the kidneys: • NEPHRONS- each is a small, independent processing unit, located mostly in Renal cortex the______, each has its own blood supply and releases fluids to a collecting duct, which leads to the ureter ______
NEPHRONS • Glomerulus: mechanically filters blood • Bowman's Capsule: mechanically filters blood • Proximal Convoluted Tubule: Reabsorbs 75% of the water, salts, glucose, and amino acids • Loop of Henle: Countercurrent exchange, which maintains the concentration gradient • Distal Convoluted Tubule: Tubular secretion of H ions, potassium, and certain drugs.
Kidney Filtration • Passing a liquid or gas through a filter to remove wastes is called filtration. • The filtration of blood mainly takes place in the part of the glomerulus nephron ____called the_____. • Nephron is a small network of capillaries ______encased in the upper end by a hollow, cupshaped structure- called the Bowman’s capsule _________
Kidney Filtration • Substance such as water, urea, glucose _________, salts, amino acids _________& some vitamins _______diffuse into the Bowman’s ______to capsule be filtrated. • The kidneys filter all the blood in the body about __________ every 45 minutes _________
Kidney Re-absorption: • Most material removed from the blood at Bowman’s capsule the _________makes its way blood into the _______ • Re-absorption is the process in which liquid is taken back into a vessel. Amino acids, fats, & glucose • ___________are reabsorbed active transport into the capillaries by_______. osmosis ____of 99% the water • Water enters by_______. is reabsorbed into the blood
Kidney Re-absorption: Urine • _______ is what remains after reabsorption. It is emptied into a collecting duct, which leads to the Ureter ______. urea, excess salts • Urine contains________, & water _____among other substances. Purified • ____blood is returned to urine is collected circulation & _______ urinary bladder in the __________.
Random Facts about Urine: • A nice cold drink of. . . urine? Although urine is sterile and made up mostly of water there are many trace amount of other chemicals and it is not recommended to drink it because of this fact. These trace chemicals give it the salty taste, but if you are generally a healthy person free of disease than tasting your urine will not harm you
Random Facts about Urine: • Urine Therapy? This is the application of urine to your body to solve all of your bodily woes such as massaging it into the skin, or ingesting it. The definition of "urine therapy" is using your urine to benefit your health. It has been claimed to alleviate itching, and an anti -cancer precaution as well as throat aches. There are certain rules to engaging in urine therapy. Urine should be sipped, not guzzled and it should be midstream urine - first thing in the morning. While using urine therapy, you should also drink plenty of water and avoid salty foods
Random Facts about Urine: • There are 45. 2% of people that pee in the shower. • There are 44. 9% of people who pee in the ocean and there are 28. 1% of people who pee in the pool.
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