Digestive System

Mouth Digestion begins in the ________ . ________ begins the process of digestion __________________- is the physical breakdown of large pieces of food into smaller pieces. __________________- large food molecules are broken down into smaller food molecules with the help of different enzymes. Mouth Chewing Mechanical digestion Chemical digestion

Mouth salivary glands _______________ secrete saliva, which contains the enzyme _________ to break the bonds in _________ (which is what type of macromolecule: ______________) and releases sugar. It also contains the enzyme __________ that fights infection by digesting the cell walls of ________ . The saliva also helps ___________ the food and make it easier to chew. The release of saliva is under the control of the ________________ amylase starches Carbohydrate lysozyme moisten bacteria nervous system

Esophagus tongue Your ________ and your _______ muscles help you swallow your food, which (after swallowing) is now called a _______ . As you swallow, the ________ closes over the _______ and the bolus enters the __________. ______ is not responsible for food going down into the stomach. throat bolus epiglottis trachea esophagus Gravity

Esophagus A series of contractions of _______ muscle squeeze the food through the ___________ . This is called _________ . A thick ring of muscle called the _____________ closes the esophagus and prevents the contents of the ________ from moving back into the esophagus (also known as acid ____). smooth peristalsis esophagus cardiac sphincter stomach reflux ***Remember: No Digestion_ occurs in the esophagus.

Stomach Food from the esophagus empties into a large muscular sac called the ___________ . Alternating contractions of the stomach’s ____ smooth muscle layers _____ and mix the ____. stomach 3 churn food

Stomach- Chemical digestion: Gastric glands The stomach contains microscopic _______________ that produce and release various substances. Some of these include: ________- a fluid that __________ and _________ the stomach wall. _______________________- makes the contents of the stomach very _______, & activates pepsin. ________- an enzyme that begins the digestion of _______ & works best under the _______ conditions One enzyme, _________ , is destroyed in the stomach due to the high level of ______ . This means that digestion of ______________ stops until the food reaches the _________________ . Mucus lubricates protects HCl (Hydrochloric Acid) acidic Pepsin acidic proteins amylase acid carbohydrates small intestine

Stomach- Mechanical digestion: Stomach muscles ________ to churn and mix the food & fluids in the stomach, producing a substance called ______ . After some time, usually about __ to __ hours, this new substance enters the ___________ through the ________ valve. contract chyme 1 2 small intestine pyloric

Small Intestine The __________ is the first part of the small intestine and is where most of the ___________ digestion and _________ of the food you eat occurs here. The small intestine is specialized to absorb _______ . The structure that aids in this absorption are the tiny folded projections called _____ . These structures increase the _____________ for absorption. Most of the products of _____________ and _______ digestion are absorbed into the ___________ in the villi. duodenum Chemical absorption nutrients villi surface area carbohydrates protein capillaries

Small Intestine Molecules of undigested ___ and some _____ acids are absorbed by ________ vessels. By the time food is ready to leave the small intestine, it is basically ________ - free….. only __________, _______, and other indigestible substances are left. Accessory structures that aid in digestion: fat fatty lymph nutrient celluluose water

Small Intestine Pancreas- produces: -_________- that help break down carbohydrates, proteins, lipids, and nucleic acids -__________________- a base that neutralizes stomach acid so these enzymes can be effective Liver- produces ____, a fluid loaded with lipids and other salts. It helps make it easier for enzymes to break down ___ . Bile is stored in the ___________ enzymes Sodium bicarbonate bile fat Gall bladder

Large Intestine Colon chyme Another name is ______. When _______ leaves the small intestine, it enters the large intestine. The function of the large intestine is to remove _______ from undigested material. Colonies of _________ produce _________ and other substances for the body to use. Concentrated _______ material that remains after ______ has been removed passes through the _________ and is eliminated from the body. water bacteria vitamin K waste water rectum

Ch. 38 Excretory System

Excretory System Functions: The _____________________from the body is know as excretion For example; lungs ___________ _________& the skin excretes _____ and ________in sweat. Therefore, the lungs and skin are part of the excretory system elimination of chemical wastes excretes carbon dioxide water salt

Excretory System Functions: The excretory system is a system of organs that remove _______from the body. The mains organ of the excretion are the __________ The removal of urea- a substance that is the result of ___________ of ________in the body cells- along with the regulation of _______ in the_______________, maintain____________, & ___________are the principal job of the kidneys waste kidneys metabolism proteins water bloodstream blood pH homeostasis

Structure of the kidneys: Each about the size of the _____ Located on either side of the _____________in the lower back Blood flows into each kidney through a _____________________Blood leaves through a ________________ fist spinal column renal artery renal vein

Structure of the kidneys: A tube called the_______, leaves each, carrying ______to the bladder. The ________________is a saclike organ where urine is stored before being excreted through a tube called the urethra ureter urine urinary bladder

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 the____________, each has its own blood supply and releases fluids to a collecting duct, which leads to the ______ Renal cortex 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 ________called the__________. Nephron is a small network of ____________encased in the upper end by a hollow, cup-shaped structure- called the __________________ glomerulus nephron capillaries Bowman’s capsule

Kidney Filtration Substance such as __________________, _________________& _____________diffuse into the ___________to be filtrated. The kidneys filter all the ____________________________________ water, urea, glucose salts, amino acids some vitamins Bowman’s capsule blood in the body about every 45 minutes

Kidney Re-absorption: Most material removed from the blood at the _________________makes its way into the _______ Re-absorption is the process in which liquid is taken back into a vessel. _____________________are reabsorbed into the capillaries by______________. Water enters by_______. ____of the water is reabsorbed into the blood Bowman’s capsule blood Amino acids, fats, & glucose active transport osmosis 99%

Kidney Re-absorption: Urine _______ is what remains after re-absorption. It is emptied into a collecting duct, which leads to the ______. Urine contains_______________, & _____among other substances. ________blood is returned to circulation & _______ is collected in the ____________________. Ureter urea, excess salts water Purified urine urinary bladder

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.