Digestive System Handout 3 PDF

SCIENCE 8 HANDOUT #3 DIGESTIVE SYSTEM 4. ELIMINATION- The removal of indigestible wastes through the anus, in The digestive system is a gro...

SCIENCE 8 HANDOUT #3 DIGESTIVE SYSTEM 4. ELIMINATION- The removal of indigestible wastes through the anus, in The digestive system is a group of organs that the form of feces. work together to digest and absorb nutrients from the food you eat. DIGESTIVE ORGANS DIGESTIVE PROCESSES 1. MOUTH- The mouth is the first organ in the digestive system where digestion 1. INGESTION- 1ST Step, it is the process begins. It serves several essential of taking in food through the mouth. functions: Ingestion, Mechanical Digestion (Chewing): Chemical 2. DIGESTION - It is the process wherein Digestion: (Saliva) Accessory Organs: food is broken down into small Teeth, Tongue, and Salivary Glands molecules that the body can use to 2. ESOPHAGUS- Its primary function is to nourish the cells and to provide energy. facilitate the passage of food or BOLUS 2 PHASES OF DIGESTION through wave-like contraction called  MECHANICAL PERISTALSIS. DIGESTION- Food is 3. STOMACH- The stomach is a hollow broken down into small muscular organ that holds food while it pieces by CHEWING or is being mixed with stomach enzymes. MASTICATION. Key functions include temporary food Mechanical Digestion storage. Mechanical digestion (through (Chewing): Teeth break muscular contractions), chemical down large food pieces digestion (via acids and enzymes) to into smaller ones. break down proteins into smaller peptides.  CHEMICAL DIGESTION- 4. SMALL INTESTINE- Organ of complete Food is acted upon by digestion and absorption. The main chemical substances functions include breaking down food, called ENZYMES. absorbing nutrients, and moving the Chemical Digestion: intestinal contents along the digestive Saliva initiates digestion tract. This is where absorption of by breaking down carbohydrates, proteins, and fats occur. starch into sugar. There is a tiny, finger-like projections in the small intestine called villi that help 3. ABSORPTION- It is the process by which absorb nutrients from food. the products of digestion are absorbed 5. LARGE INTESTINE- The large intestine, by the blood to be supplied to the rest also known as the COLON. It has of the body. essential functions, such as temporary stores fecal materials and reabsorb  water and electrolytes from the 4. LIVER- The liver, the largest internal undigested residue. organ in the body, performs 6. RECTUM- The rectum connects the essential functions within the large intestine to the anus. It acts as a digestive system. It produces bile reservoir where stool accumulates for fat emulsification, aiding fat before being ready for elimination. digestion, transport fat, filters toxins such as drugs, alcohol, and caffeine 7. ANUS- marks the exit point for food from the bloodstream. waste. 5. GALLBLADDER- The gallbladder is a small, pear-shaped organ located ACCESSORY ORGANS beneath the liver. Its primary role in 1. TEETH AND TONGUE the digestive system is to store and 2. SALIVARY GLANDS- a gland in the concentrate bile produced by the mouth that produces saliva which liver. has an enzyme called Salivary Bile is a sticky, yellow-green Amylase or Ptyalin that works on digestive fluid. Its primary function breaking down carbohydrates or is to break down fats into fatty acids starch. during digestion. 3. PANCREAS- The pancreas is located behind the stomach; it performs ENZYMES- A biological catalysts and is two key functions: it produces almost always a protein. It speeds up enzymes that break down sugars, the rate of a specific chemical reaction fats, proteins, and carbohydrates to break down food into smaller during digestion and produces absorbable units. They speed up the insulin to help regulate blood sugar chemical breakdown of food by levels. Some of the enzymes that lowering the energy needed for the pancreas produced are amylase, reactions. lipase, and trypsin. CHEMICAL DIGESTION OF CARBOHYDRATES Begins in the mouth and ends in the small intestine PTYALIN- an enzyme found in the saliva of humans and some other animals. Carbohydrates has 3 simplest units: glucose, fructose, and galactose. CHEMICAL DIGESTION OF PROTEINS Begins in the stomach and ends in the small intestine. PEPSIN- enzyme in the stomach that breaks down proteins in food during digestion. PEPTIDES- a molecule that contains two or more amino acids. TRYPSIN- an enzyme that breaks down proteins in the small intestine produce by the pancreas. AMINO PEPTIDASES- enzymes that break down amino acid residues EREPSIN- mixture of enzymes that breaks down proteins into amino acids. CHEMICAL DIGESTION OF FATS Begins and ends in the small intestine. PANCREATIC STEAPSIN- enzyme that breaks down fats into glycerol and fatty acids. CHEMICAL DIGESTION OF NUCLEIC ACID Begins and ends in the small intestine. NUCLEASE- an enzyme that breaks down nucleic acids. NUCLEOTIDASE- an enzyme that breaks down nucleotides into nucleosides and phosphate. NUCLEOSIDASE- an enzyme that breaks down nucleoside. NUCLEOTIDE- is a molecule that serves as the basic building block of DNA and RNA.  IMPORTANCE OF ENZYME Its key role is breaking down the food you eat. It speeds up the chemical reactions that turn nutrients into substances that your digestive tract can absorb. DIGESTIVE SYSTEM INTERACTIONS immune system, tissue and organ damage. 1. CIRCULATORY SYSTEM- supplies 3. DYSFUNCTION IN PANCREAS oxygen to the different organs - When pancreas doesn’t produce through blood. It also carries away enough pancreatic juice it can lead nutrients and transports them to to inadequate digestion, various cells in the body. malnutrition, weight loss, diarrhea, 2. RESPIRATORY SYSTEM- supplies the and diabetes. different digestive organs with the 4. DYSFUNCTION IN LIVER oxygen they need, at the same time - Not having enough bile affects your it removes carbon dioxide which is digestive system’s ability to absorb expelled out of the body through fats and the fat-soluble vitamins A, the lungs. D, E and K can lead to malnutrition. 3. EXCRETORY SYSTEM- Excess water Yellowing of skin and eyes, dark exits in the body in the form of urine, light-colored stools and urine and through perspiration. itching of skin are some of the signs GLUCOSE, FRUCTOSE, GALACTOSE of liver disease. - Absorb by the capillaries and brought to liver 5. DYSFUNCTION IN GALLBLADDER - Excess glucose is stored as glycogen in the liver - Lack of bile can lead to digestive - Amino acids are also absorbed by the difficulties especially after eating capillaries. They are use bringing about growth fatty foods. It can cause pain (right and repair of damaged tissues upper abdomen), nausea and - Excess amino acids are broken down in the vomiting, abdominal bloating, and liver and excreted as UREA malnutrition. - Fatty acids and glycerol used as energy sources 6. DYSFUNCTION IN LARGE INTESTINE DIGESTIVE SYSTEM DISORDERS - Malfunction in large intestine can 1. MALFUNCTION OR DYSFUNCTION IN lead to diarrhea or constipation. STOMACH - You can’t digest food properly or absorb its nutrients. This led to 6 ESSENTIAL NUTRIENTS indigestion, malnutrition, and 1. CARBOHYDRATES- grains (cereals, sometimes bacterial overgrowth. bread, root crops), fruits (banana, 2. DYSFUNCTION IN SMALL INTESTINE grapes, pineapple) and vegetables (peas - If the small intestine can’t absorb and beans). There are 2 types of nutrients properly and fluids to carbohydrates which are the starch and meet the body’s needs sugar. Sugar can be used as energy complications include dehydration, faster than starch. Too much starch malnutrition, lactose intolerance, store in muscle and may lead to incomplete digestion, weakened overweight.  2. PROTEINS- use to repair and build acidity and basicity in the body. It also tissue. Example of foods with proteins helps in regulating water in the body. are meat, fish, eggs, milk (complete Examples: calcium found in milk, iodine protein), rice, beans and cereals in seafood, and potassium found in (incomplete protein). Protein changes fruits. to amino acid which is taken up by the 5. VITAMINS- Also used to build and repair cell. tissues, use for proper growth and 3. FATS AND OILS- provide energy but it is function of the body. there are two twice as much as what carbohydrates groups of vitamins which are the water- provide. Most stored fuel in your body soluble- vitamins that can dissolve in is in the form of fats and it serves as water (ex. vitamin c, vitamin b complex insulator from the cold. Salad oil, easily washed away from the body.) and cheese, margarine, and butter are fat-soluble vitamin- vitamins that can example of foods with fats. Also, fats dissolve in fat (ex. vitamin a, d, e, k). and oil become fatty acid and they will Reduced vitamin intake impairs be use by the cell. It offers the highest metabolic pathways and may lead to energy per gram and are ideal for nutrient deficiency. sustained, long duration energy. 6. WATER- you may drink water or may get 4. MINERALS- those are the Inorganic it from the food you eat. Water is substances that helps in maintaining essential in dissolving food materials. NUTRIENT DEFICIENCY 1. ANEMIA- when you are anemic, you lack iron. Iron is needed in the formation of hemoglobin, which is the red substance in the blood. When you have anemia, your blood is pale and you will easily feel tired. Iron is abundant in liver, red meat, egg yolk, and leafy green vegetables. 2. GOITER- when you have goiter, you lack iodine. Iodine is present in seafood and iodized salt. When a body lacks iodine, the thyroid gland enlarges, making the base of your neck bulge known as goiter. 3. SCURVY- when you lack vitamin C or ascorbic acid, there is a tendency for a person to have scurvy. People suffering from scurvy may experience weakness, muscle pain, and bleeding of gums. To avoid scurvy, eat citrus fruits like orange and lemon. PROBLEMS THAT AFFECT DIGESTIVE SYSTEM AND THEIR TREATMENT 1. CONSTIPATION- if the wastes in your large intestine are not removed regularly, the condition may result to constipation. Constipation is defines as having less than three times of bowel movement per week. To avoid constipation, you should eat foods rich in fiber such as fruits, vegetables, and whole grains. Drink lots of fluids in the morning, at least 6-8 glasses of water every day. 2. DIARRHEA- is a condition where your stool becomes watery and loose. This happens when the intestine pushes the stool out of the body before it absorbs the water. Diarrhea may result to dehydration and irritation in the anus. If you are suffering from diarrhea, take water or rehydration drink frequently to restore the water lost. You may also take medicine if you have a mild case of diarrhea. 3. COLON CANCER- is cancer in large intestine which affect its ability to absorb water and electrolytes. It is caused by the uncontrolled growth of cells in the colon. Symptoms of colon  cancer involve worsening of constipation. Chronic diarrhea, blood in stool, narrow stools, weight loss, and vomiting. Medication and healthy lifestyle may prevent colon cancer. If diagnosed early, radiation therapy and surgery can be done. 4. HEARTBURN- when you experience a backflow of gastric juices into your esophagus, you will feel heartburn or a burning sensation in your chest. To avoid heartburn, your diet should consist of low-fat and fiber-rich foods. Avoid carbonated drinks and caffeine that may relax your sphincter and increase acidity of your stomach. DETECTION AND PREVENTION OF DISEASES OF THE DIGESTIVE SYSTEM DETECTION- because of modern technology, one can detect diseases of the digestive system. There are several examinations that can identify these ailments. A. COLONOSCOPY is an examination of the inside of the colon. Doctors use a long, flexible fiber- optic tube to view the inside of the colon. B. ENDOSCOPY- is also used to detect ailments in the alimentary canal. Endoscopy uses a device that can examine the insides of a hollow organ. It includes capsule endoscopy and the endoscopic ultrasound. PREVENTION 1. CHEW YOUR FOOD. When you eat, slowly chew your food because it will assist you in the digestion of food. 2. WATCH YOUR EATING HABITS. If you have a fixed time for your meals, your digestive system has a time to receive food. Do not eat more than an amount that will make you bloat or eat less than an amount that will make you too hungry. You should also have frequent small meals since they will help you burn up calories regularly. 3. EAT A BALANCED DIET. When you eat, you should consider that you have the five food groups. Be wary of the amount of foods you take. Eat less sugar and salt. Take in more protein and high fiber. You should eat fruits and vegetables regularly. 4. AVOID SPICY, SOUR, OR OILY FOOD. Too spicy and too sour food will hurt your digestive system. Avoid caffeine and carbonated drinks. They increase the acidity of your stomach. Oily food slows down digestion. 5. OBSERVE PROPER HYGIENE. Make sure the food you eat is clean and your hands are clean to avoid food poisoning. Also check the expiry date of your food items and dispose of them properly. Brush your teeth in the morning and before going to bed. This will prevent cavities and tooth decay. A good set of teeth helps in the chewing of food. 6. HAVE A REGULAR BOWEL MOVEMENT. To avoid constipation, you should have regular bowel movement. Eat fiber-rich food and drink eight glasses of water every day. 7. HAVE A REGULAR EXERCISE. Exercise and other physical activities enhance the function of the digestive system.