Digestive System Quiz
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Questions and Answers

What is the primary function of the digestive system?

  • To break down large food molecules and absorb nutrients (correct)
  • To eliminate waste without nutrient absorption
  • To store food for prolonged periods
  • To absorb vitamins and minerals only

Which accessory organ is responsible for producing bile?

  • Pancreas
  • Gall bladder
  • Liver (correct)
  • Salivary glands

What is the role of incisors in the mouth?

  • To crush and grind food
  • To hold food in place
  • To tear food
  • To cut food (correct)

What condition results from a chronic inflammation of the gums?

<p>Periodontal disease (C)</p> Signup and view all the answers

Which of the following structures serves as a voiding mechanism for waste material?

<p>Rectum (C)</p> Signup and view all the answers

What is the primary role of salivary amylase in saliva?

<p>To begin breaking down carbohydrates (C)</p> Signup and view all the answers

During the involuntary phase of swallowing, which structure closes off the trachea?

<p>Epiglottis (A)</p> Signup and view all the answers

What is the function of the lower esophageal sphincter?

<p>To separate the esophagus from the stomach (D)</p> Signup and view all the answers

What is the primary function of gastric juices in the stomach?

<p>To digest proteins (A)</p> Signup and view all the answers

Which component of saliva helps to lubricate food and hold it together for swallowing?

<p>Mucin (B)</p> Signup and view all the answers

What initiates peristalsis in the esophagus?

<p>Reflexive muscle contractions (B)</p> Signup and view all the answers

Which of the following substances is NOT absorbed in the stomach?

<p>Protein (B)</p> Signup and view all the answers

What condition is often caused by a Helicobacter pylori infection?

<p>Stomach ulcers (D)</p> Signup and view all the answers

Which type of carbohydrates provides more vitamins and minerals due to not having parts of the grain removed?

<p>Brown rice (C)</p> Signup and view all the answers

Which of the following is considered a healthy unsaturated fat?

<p>Olive oil (B)</p> Signup and view all the answers

What can excessive intake of LDL cholesterol potentially lead to?

<p>Heart attack (A)</p> Signup and view all the answers

Which of the following includes all essential amino acids for the body?

<p>Eggs (A)</p> Signup and view all the answers

What is a good source of vitamin A?

<p>Egg yolk (D)</p> Signup and view all the answers

What deficiency is associated with a lack of vitamin D?

<p>Rickets (C)</p> Signup and view all the answers

Which vitamin is primarily obtained from green leafy vegetables and is crucial for blood clotting?

<p>Vitamin K (D)</p> Signup and view all the answers

Which food source is not associated with vitamin C production?

<p>Egg yolk (C)</p> Signup and view all the answers

What is the primary function of stomach contractions during digestion?

<p>To blend food and expose it to gastric juices (D)</p> Signup and view all the answers

What substance is secreted by the pancreas to neutralize acid from the stomach?

<p>Sodium bicarbonate (D)</p> Signup and view all the answers

What role does bile play in digestion?

<p>It emulsifies fats into smaller droplets. (D)</p> Signup and view all the answers

Which part of the small intestine is primarily responsible for the absorption of nutrients?

<p>Jejunum (A)</p> Signup and view all the answers

How do fatty acids and monoglycerides enter the epithelial cells of the small intestine?

<p>Diffusion across the cell membrane (A)</p> Signup and view all the answers

What structures in the small intestine increase the surface area for absorption?

<p>Microvilli and villi (D)</p> Signup and view all the answers

What type of movement occurs in the small intestine to mix contents and maximize nutrient absorption?

<p>Segmentation (A)</p> Signup and view all the answers

What process occurs with triglycerides after absorption in the small intestine?

<p>They reform into triglycerides and join with proteins for transport. (B)</p> Signup and view all the answers

What significantly influences Basal Metabolic Rate (BMR) in individuals?

<p>A combination of gender, body composition, age, stress, food intake, and genetics (D)</p> Signup and view all the answers

Which dietary practice is recommended for maintaining a healthy weight?

<p>Consume more small meals throughout the day and stop eating when full (A)</p> Signup and view all the answers

Which of the following foods is considered beneficial for lowering blood cholesterol?

<p>Fruits with high soluble fiber such as apples and bananas (C)</p> Signup and view all the answers

Why should one avoid consuming junk foods and fast foods?

<p>They are high in salt, simple sugars, saturated fats, and trans fats while being low in vitamins and minerals (C)</p> Signup and view all the answers

What is the role of soluble and insoluble fibers in the diet?

<p>They aid in digestion and help prevent chronic diseases like colon cancer (C)</p> Signup and view all the answers

What is a common source of iron in the diet?

<p>Whole grains (A)</p> Signup and view all the answers

Which deficiency is specifically noted for women due to blood loss?

<p>Iron (A)</p> Signup and view all the answers

What role do antioxidants play in the body?

<p>Protect DNA from damage (C)</p> Signup and view all the answers

Which mineral is associated with the formation of thyroid hormones?

<p>Iodine (B)</p> Signup and view all the answers

What is a potential health risk associated with obesity?

<p>Increased likelihood of gallstones (A)</p> Signup and view all the answers

What is the caloric content of a gram of fat?

<p>9 calories (D)</p> Signup and view all the answers

Which food is recommended for its antioxidant properties?

<p>Spinach (A)</p> Signup and view all the answers

What happens to excess calories in the body?

<p>They are converted to glycogen or fat (A)</p> Signup and view all the answers

What part of the digestive system is primarily responsible for enzymatic digestion of carbohydrates?

<p>Mouth (D)</p> Signup and view all the answers

Which teeth are primarily responsible for crushing and grinding food?

<p>Molars (B)</p> Signup and view all the answers

What condition is caused by bacteria in the mouth leading to the production of acids?

<p>Tooth decay (D)</p> Signup and view all the answers

Which structure in the digestive tract helps separate the acidic environment of the stomach from other regions?

<p>Pyloric sphincter (D)</p> Signup and view all the answers

What is the role of the tongue during the digestive process?

<p>Positioning food for teeth (C)</p> Signup and view all the answers

What is the role of bicarbonate in saliva?

<p>It counteracts acid produced by bacteria. (C)</p> Signup and view all the answers

Which component of gastric juice is responsible for killing most bacteria?

<p>Hydrochloric acid (D)</p> Signup and view all the answers

During the swallowing reflex, which action occurs first?

<p>The tongue pushes food into the pharynx. (D)</p> Signup and view all the answers

What is the primary function of the lower esophageal sphincter?

<p>It stops stomach acid from entering the esophagus. (D)</p> Signup and view all the answers

What role does saliva play in carbohydrate digestion?

<p>It contains salivary amylase, which begins breaking down carbohydrates. (C)</p> Signup and view all the answers

What is the primary function of mucus in the esophagus?

<p>To assist in food motility. (B)</p> Signup and view all the answers

Which part of the digestive system is primarily responsible for the storage of food?

<p>Stomach (A)</p> Signup and view all the answers

What can lead to the formation of ulcers in the stomach?

<p>Infection caused by Helicobacter pylori (A)</p> Signup and view all the answers

What factor contributes to a higher Basal Metabolic Rate (BMR) in males compared to females?

<p>Greater muscle mass (C)</p> Signup and view all the answers

Which of the following diets is most likely to lower BMR due to the body's adaptive response to low energy intake?

<p>Low-calorie diet (A)</p> Signup and view all the answers

What is a significant dietary recommendation for preventing constipation and promoting overall digestive health?

<p>Consume more soluble and insoluble fibers (B)</p> Signup and view all the answers

Which of the following components is key to a healthy diet as recommended in maintaining overall health?

<p>Eating a variety of foods (A)</p> Signup and view all the answers

What type of foods should be minimized to improve heart health by lowering cholesterol levels?

<p>Junk foods and fast foods (B)</p> Signup and view all the answers

What is the primary function of the hepatic portal system?

<p>Transporting blood from the digestive tract to the liver (C)</p> Signup and view all the answers

Which of the following functions is NOT associated with the liver?

<p>Storing excess water (A)</p> Signup and view all the answers

How are fat-soluble vitamins transported in the body?

<p>Similar to fats in the bloodstream (D)</p> Signup and view all the answers

What major role does the colon play in the digestive system?

<p>Storage and elimination of waste (B)</p> Signup and view all the answers

Which of the following statements about carbohydrates is accurate?

<p>Complex carbohydrates can be stored as glycogen. (D)</p> Signup and view all the answers

What is one of the functions of bacteria residing in the colon?

<p>Generating gas and certain vitamins (C)</p> Signup and view all the answers

What happens to excess cholesterol removed from the blood by the liver?

<p>It is excreted in bile. (A)</p> Signup and view all the answers

Which nutrients are primarily absorbed through osmosis in the intestines?

<p>Water (B)</p> Signup and view all the answers

Which type of fat is generally considered unhealthy and is often found in processed foods?

<p>Trans fats (A)</p> Signup and view all the answers

Which food combination is essential for strict vegetarians to obtain all essential amino acids?

<p>Rice and beans (D)</p> Signup and view all the answers

What is a significant consequence of consuming too much LDL cholesterol?

<p>Risk of heart attacks (B)</p> Signup and view all the answers

Which vitamin is primarily obtained from UV light on skin and is essential for calcium absorption?

<p>Vitamin D (C)</p> Signup and view all the answers

What nutrient deficiency can lead to severe bleeding and hemophilia?

<p>Vitamin K (D)</p> Signup and view all the answers

Which of the following foods is a good source of Vitamin C?

<p>Broccoli (D)</p> Signup and view all the answers

What type of carbohydrates provides a higher amount of vitamins and minerals due to retaining the grain's parts?

<p>Whole carbohydrates (C)</p> Signup and view all the answers

Which condition is associated with a deficiency of calcium absorption due to a lack of Vitamin D?

<p>Rickets (A)</p> Signup and view all the answers

What is the primary purpose of bile in the digestive process?

<p>To emulsify fats for digestion (C)</p> Signup and view all the answers

What happens to chyme with high fat content during digestion?

<p>It slows delivery to the small intestine (D)</p> Signup and view all the answers

What mechanism is responsible for increasing the surface area of the small intestine for absorption?

<p>Villi and microvilli (C)</p> Signup and view all the answers

How are amino acids and monosaccharides transported into the bloodstream after absorption?

<p>By active transport into epithelial cells (A)</p> Signup and view all the answers

What role does segmentation play in the small intestine?

<p>Enhancing nutrient absorption through mixing (D)</p> Signup and view all the answers

What is the initial pH of the chyme before neutralization in the duodenum?

<p>Acidic (pH below 7) (D)</p> Signup and view all the answers

During digestion, what do fatty acids reform into once absorbed by epithelial cells?

<p>Triglycerides (A)</p> Signup and view all the answers

What contributes to the slow delivery of chyme to the small intestine?

<p>Hormones released by the small intestine (D)</p> Signup and view all the answers

Flashcards

Digestive System Components

The gastrointestinal tract (a continuous tube) and accessory organs work together to break down and absorb food.

Teeth Function

Teeth have specialized shapes (incisors, canines, molars) for different tasks: cutting, tearing, and grinding food.

Tooth Decay Cause

Bacteria in the mouth produce acids that damage tooth enamel, leading to decay.

Mouth Digestion

Carbohydrate digestion begins in the mouth with enzymes.

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Taste Buds

Taste buds on the tongue detect five basic tastes: sweet, sour, salty, bitter, and umami.

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Saliva composition

Saliva is made of water, mucin, salivary amylase, bicarbonate, and lysozyme.

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Swallowing process

Swallowing starts voluntarily, then becomes a reflex with the pharynx and epiglottis playing key roles, moving food into the esophagus.

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Pharynx function

The pharynx is a common passageway for both air and food.

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Esophagus function

The esophagus connects the pharynx to the stomach, using mucus and peristalsis to move food.

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Stomach function

The stomach stores food, digests proteins via acids and enzymes, regulates food delivery to the small intestine, and kills bacteria.

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Gastric juice composition

Gastric juice contains hydrochloric acid, pepsinogen (which becomes pepsin), and mucus.

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Acid reflux problem

Acid reflux is painful and can cause esophageal ulcers and cancer; it occurs when stomach acid flows back into the esophagus.

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Stomach ulcers

Stomach ulcers form when the lining of the stomach isn't protected enough from the acidic environment; often due to bacterial infection, or use of aspirin, alcohol, and smoking

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Brown Carbohydrates

Whole grains that retain their bran and germ, offering more vitamins, minerals, and fiber compared to refined grains.

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Unsaturated Fats

Healthy fats that are liquid at room temperature, found in sources like olive oil, avocados, and nuts.

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Saturated Fats

Fats that are solid at room temperature, found in sources like butter, red meat, and coconut oil.

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Trans Fats

Unhealthy fats created through a process called hydrogenation, found in processed foods like cookies and margarine.

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Essential Amino Acids

Eight amino acids that the body cannot produce and must be obtained through diet.

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Vitamin A

A vitamin crucial for vision, skin health, and immune function, found in sources like carrots, sweet potatoes, and fish oil.

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Vitamin D

A vitamin essential for calcium absorption, bone health, and immune function, found in sources like sunlight, fortified milk, and fatty fish.

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Vitamin C

A vitamin vital for collagen production, wound healing, and immune function, found in sources like oranges, lemons, and broccoli.

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Basal Metabolic Rate (BMR)

The amount of energy your body burns at rest, accounting for about 70% of your total energy use.

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Factors Influencing BMR

Gender, body composition, age, stress, food intake, and genetics all affect your BMR.

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Why Exercise is Key for Weight Loss

While dieting can reduce calories, exercise helps burn off excess calories and prevent a slower metabolism, making it crucial for long-term weight management.

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Healthy Diet Components

A balanced diet focuses on whole grains, vegetables, fruits, low-fat proteins, and low-fat dairy products.

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Why Variety is Important in Diet

Eating different foods ensures you receive all the essential nutrients, including amino acids, minerals, vitamins, and lipids.

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What is Chyme?

Chyme is the partially digested, acidic mixture of food and gastric juices that forms in the stomach.

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How does the duodenum neutralize stomach acid?

The duodenum receives bicarbonate ions from the pancreas, which neutralizes the acidic chyme from the stomach, raising the pH to around 8.

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What is the role of Bile?

Bile is produced by the liver and stored in the gallbladder. It breaks down fat molecules into smaller droplets (emulsification) for easier digestion and absorption.

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Where does most nutrient absorption occur?

Most nutrient absorption takes place in the jejunum and ileum, the middle and lower sections of the small intestine.

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How does the small intestine maximize surface area?

The small intestine has folds, villi, and microvilli, which greatly increase its surface area, allowing for efficient nutrient absorption.

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What is segmentation?

Segmentation is a type of muscle contraction in the small intestine that produces 'random' movements that mix food and press it against the mucosa for absorption.

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How are amino acids absorbed?

Amino acids are actively transported from the small intestine into epithelial cells and then diffuse into capillaries.

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How are fats absorbed?

Fatty acids and monoglycerides diffuse into epithelial cells, reassemble into triglycerides, and are transported into lymph capillaries.

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Calcium's Role

Calcium is essential for bone and tooth formation, as well as nerve and muscle function.

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Calcium Deficiency

A lack of calcium can lead to stunted growth and osteoporosis, a condition that weakens bones.

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Iron's Role

Iron is crucial for making hemoglobin, the protein in red blood cells that carries oxygen throughout the body.

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Iron Deficiency

Insufficient iron leads to anemia, characterized by fatigue and weakness due to a lack of oxygen in the blood.

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Iodine's Role

Iodine is vital for the production of thyroid hormone, which regulates metabolism and growth.

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Iodine Deficiency

A lack of iodine causes an enlarged thyroid gland, known as goiter.

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Antioxidants: What They Do

Antioxidants donate electrons to free radicals, preventing them from damaging DNA and potentially leading to cancer.

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Excess Calories: Storage

Any excess calories, regardless of source (carbs, fats, or proteins), are converted to glycogen or fat, which is stored in adipose tissue cells.

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What are the four key components of a balanced diet?

A balanced diet consists of proteins, fats, sugars and nucleic acids for building cells, vitamins and minerals for cellular functions, water for hydration, and energy sources for powering activities.

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What is the 'gastrointestinal tract'?

The gastrointestinal tract is a continuous tube that runs from the mouth to the anus, responsible for digesting and absorbing nutrients.

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What are the roles of accessory organs in digestion?

Accessory organs, such as salivary glands, liver, gallbladder, and pancreas, assist in digestion. Salivary glands produce saliva, the liver produces bile, the gallbladder stores bile, and the pancreas releases digestive enzymes.

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What is the function of the tongue in digestion?

The tongue, a muscular organ, helps position food for teeth, helps in chewing, and possesses taste buds that detect five tastes: sweet, sour, salty, bitter, and umami.

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What is the role of teeth in digestion?

Teeth break down food mechanically. Incisors cut, canines tear, and molars crush and grind food into smaller pieces for easier digestion.

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Gastric Pits

Small indentations in the stomach lining that contain cells that secrete gastric juice (a mixture of hydrochloric acid, pepsinogen, and mucus).

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Peristalsis in Stomach

Muscle contractions in the stomach that mix food with gastric juice and push it towards the small intestine.

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Chyme

The partially digested, acidic mixture of food and gastric juice that leaves the stomach and enters the small intestine.

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Duodenum's Role

The first part of the small intestine where chyme is neutralized, fats are emulsified by bile, and digestive enzymes are added.

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Bile's Function

Bile, made by the liver, breaks down fat droplets into smaller ones, making it easier to digest and absorb.

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Small Intestine Absorption

The majority of nutrient absorption (95%) takes place in the jejunum and ileum of the small intestine.

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Segmentation

A type of muscle contraction in the small intestine that mixes food and presses it against the inner wall to enhance absorption.

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Amino Acid & Fat Absorption

Amino acids are actively transported into cells and then enter capillaries, while fats pass into cells, reform, and enter lymph capillaries.

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What does saliva do?

Saliva is made in the mouth and helps us swallow by moistening food and mixing with it, it also contains enzymes that start breaking down carbohydrates.

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Why does the epiglottis close?

When you swallow, the epiglottis covers the opening of the trachea (windpipe) to prevent food from entering the lungs.

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What is peristalsis?

Peristalsis is the rhythmic muscular contractions that move food through your digestive tract, pushing it along like a wave.

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Why is the stomach so acidic?

The stomach has strong acids that help break down food and kill bacteria. It also contains enzymes that start digesting proteins.

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How does mucus protect the stomach?

The stomach lining is covered in mucus, a sticky substance that protects it from the harmful acids inside.

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What is acid reflux?

Acid reflux occurs when stomach acid flows back up into the esophagus, causing painful burning sensations. This can happen when the lower esophageal sphincter (LES) doesn't close properly.

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What causes ulcers?

Ulcers are sores in the stomach lining caused by bacteria (Helicobacter pylori), smoking, alcohol, and regular use of aspirin.

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What is the Heimlich maneuver?

The Heimlich maneuver is a life-saving technique used to dislodge objects blocking the airway. It involves forceful upward thrusts in the abdomen to force air out of the lungs and propel the object out.

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Factors affecting BMR

Gender, body composition, age, stress, food intake and genetics all influence how much energy your body burns at rest.

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What is the hepatic portal system?

A special blood vessel network that carries blood from the digestive tract (stomach, small intestine, large intestine) directly to the liver before entering general circulation.

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What does the liver store?

The liver stores glucose as glycogen, fat-soluble vitamins (like A, D, E, and K), and some lipids (fats).

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What does the liver manufacture?

The liver produces fibrinogen and albumin (blood proteins), some lipids, and bile (from cholesterol).

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What does the liver detoxify?

The liver breaks down poisons, including drugs and alcohol, and converts ammonia (toxic) to urea (less harmful for excretion).

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What is the function of the large intestine?

The large intestine absorbs remaining nutrients and water, stores waste, and eliminates it through the rectum and anus.

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What are the parts of the large intestine?

The large intestine consists of the cecum (with the appendix), colon (ascending, transverse, descending, sigmoid), rectum, and anus (with sphincters).

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What bacteria live in the large intestine?

The large intestine is home to bacteria that produce essential vitamins (biotin, Vitamin K, and B6) but also generate gas.

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What is the difference between simple and complex carbohydrates?

Simple sugars provide a quick burst of energy but lead to spikes and crashes in blood sugar. Complex carbohydrates are digested slowly, providing sustained energy.

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Brown vs. White Carbs

Brown carbs (like brown rice and bread) contain the whole grain, including bran and germ, which provide more vitamins, minerals, and fiber compared to white carbs, where these parts are removed.

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Healthy Fats

Healthy fats, called unsaturated fats, are liquid at room temperature and include oils like olive oil, canola oil, and sunflower oil.

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Unhealthy Fats

Unhealthy fats include saturated fats and trans fats. Saturated fats are solid at room temperature and found in foods like butter, while trans fats are created through a process called hydrogenation and are found in many processed foods.

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Vitamin A: Good Sources

Vitamin A is crucial for vision, skin health, and immune function. Good sources include yellow, orange, and green leafy vegetables, as well as fish, egg yolk, and liver.

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Vitamin D: Good Sources

Vitamin D is essential for calcium absorption and bone health. Good sources include UV light, fortified milk, oily fish, and egg yolk.

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Vitamin K: Good Sources

Vitamin K is important for blood clotting. Good sources include bacteria in the large intestine and green leafy vegetables.

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Vitamin C: Good Sources

Vitamin C is needed for collagen production and wound healing. Good sources include citrus fruits, berries, and certain vegetables like broccoli, brussel sprouts, peppers, and cabbage.

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Study Notes

Digestion and Nutrition Overview

  • Cells require raw materials (proteins, fats, sugars, nucleic acids) and energy sources (vitamins, minerals, water) for construction and function.
  • Large food molecules are broken down into smaller molecules by the digestive system, absorbed, and transported to cells for immediate use or storage.
  • Undigested materials are eliminated during defecation.

Digestive System

  • The gastrointestinal tract is a hollow tube, encompassing the mouth, pharynx, esophagus, stomach, small intestine, large intestine, rectum, and anus.
  • Sphincters regulate the passage of food and control defecation.
  • Accessory organs (salivary glands, liver, gallbladder, and pancreas) support digestion.

Mouth and Teeth

  • Teeth (incisors, canines, molars) mechanically break down food.
  • Enamel is hard, non-living tissue. Dentin is living, bone-like tissue with blood vessels and nerves.
  • Wisdom teeth are vestigial.
  • Plaque, a sticky film of bacteria, can harden into tartar and cause tooth decay.
  • Gingivitis is gum infection/inflammation due to bacterial toxins, which can lead to periodontal disease and tooth loss.

The Mouth

  • The mouth initiates carbohydrate digestion with salivary amylase.
  • The tongue positions food for chewing and has taste buds (sweet, sour, salty, bitter, umami).
  • Saliva contains water, mucin, salivary amylase, bicarbonate, lysozyme, and helps in lubrication for swallowing and holds food together. Salivary glands secrete saliva.

Swallowing

  • Swallowing (deglutition) involves voluntary and involuntary phases.
  • The voluntary phase involves pushing food into the pharynx.
  • The involuntary phase involves a reflex, closing off the nasal passages and trachea, and propelling food into the esophagus.

Pharynx and Esophagus

  • The pharynx is a common passage for air and food.
  • The esophagus connects the pharynx to the stomach.
  • Mucus facilitates smooth passage of food.
  • Peristalsis and gravity move food through the esophagus.
  • The lower esophageal sphincter prevents acid reflux, which can cause painful esophageal ulcers and cancer.

Stomach Function

  • The stomach stores food, mechanically mixes it, begins protein digestion via pepsinogen to pepsin, and regulates delivery to the small intestine.
  • It produces gastric juice containing hydrochloric acid (low pH), pepsinogen and mucus, which helps protect the stomach lining from acid.
  • The stomach has three layers of muscle to mix chyme.
  • Absorption is limited to a few things—alcohol and aspirin.

Stomach Contraction

  • Involves a process of mixing and moving food along the tract called peristalsis.
  • The stomach muscles blend food with enzymes and push it into the small intestine in portions called chyme.
  • Rate of chyme release depends on food type (fat is slower digestion).

Small Intestine

  • The duodenum is the beginning portion of the small intestine (first 25 cm).
  • Neutralization of stomach acid (pH adjustment by sodium bicarbonate from the pancreas).
  • Bile is produced by the liver and stored in the gallbladder; it emulsifies fats, breaking them down into smaller droplets aiding digestion and absorption.
  • Enzymes for carbohydrate, protein, nucleic acid, and fat digestion are secreted by the pancreas and the small intestine itself.
  • Absorption of nutrients into blood and lymph.

Small Intestine Absorption

  • Huge surface area for absorption inside the small intestine is increased by folds, villi (finger-like projections), and microvilli (small projections on the villi).
  • Absorption of nutrients (monosaccharides, amino acids, fatty acids, etc.) which takes place in the jejunum and ileum.
  • Specialized transport mechanisms facilitate nutrient uptake.
  • Segmentation (contractions mix chyme to maximize contact with mucosa).

Absorption of Nutrients and Water

  • Amino acids and monosaccharides are actively transported into the epithelial cells. They are then transported to the capillaries.
  • Fats diffuse into cells, reform into triglycerides, and combine with proteins, enter the lymphatic system. The lymph then joins with the blood circulation.
  • Vitamins and minerals are absorbed via active transport or diffusion.
  • Water is absorbed by osmosis.

Large Intestine

  • Absorbs water and certain nutrients (like some vitamins produced by bacteria).
  • Stores waste matter (feces).
  • Bacteria thrive in the colon, producing vitamins K and B vitamins.
  • The appendix is a vestigial structure associated with the large intestine; can lead to appendicitis if infected.

Nutrition: Carbohydrates, Lipids, Proteins, Vitamins

  • Carbohydrates provide energy. Complex carbohydrates are digested slowly, while simple sugars cause quick spikes in blood sugar and insulin.
  • Lipids (fats) also provide energy. Unsaturated fats are healthier than saturated fats, which increase 'bad' cholesterol.
  • Proteins are composed of amino acids, some essential (must be ingested) and others produced by the body. Animal proteins contain all essential amino acids.
  • Vitamins are crucial for various bodily functions. Mostly they cannot be made by the body and need to be ingested. Deficiencies result in health problems.

Nutrition: Minerals

  • Minerals are essential for various bodily functions, including bone formation, nerve function, and blood production. Calcium is needed for bone development, and iron is essential for hemoglobin.
  • Specific minerals and their associated functions and food sources are discussed including calcium, iron, iodine, zinc—sources, importance and deficiencies.

Nutrition: Antioxidants

  • Antioxidants protect the body against free radicals that can damage DNA.
  • Various foods rich in antioxidants are highlighted, including fruits and vegetables.

Energy and Weight Control

  • Excess calories are stored as fat.
  • Healthy diets emphasize complex carbohydrates, lean proteins, and healthy fats.
  • Regular exercise is essential for calorie expenditure.
  • Avoiding simple sugars, saturated fats, trans fats, and unhealthy foods (junk foods) is important for weight control.
  • Eating too many calories results in weight gain and potential health risks.

Health Risks Associated with Obesity

  • Obesity can increase the risk of several health problems, including high blood pressure, type II diabetes, cancer, sleep apnea, gout, and osteoarthritis.

General Tips for Healthy Eating

  • Consume a diverse range of foods.
  • Maintain a healthy weight through exercise and diet control.
  • Increase consumption of fruits and vegetables (for vitamins, minerals and fiber).
  • Eat a variety of foods and enough quantities of each.
  • Control intake of simple sugars, saturated fats, cholesterol, and trans fats.
  • Consume sufficient amounts of proteins, carbohydrates, and healthy fats while limiting simple sugars.
  • Drink adequate amounts of water, and exercise regularly.

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Description

Test your knowledge about the digestive system, its functions, and the roles of various organs involved in digestion. This quiz covers the primary functions of the digestive components, the roles of enzymes and sphincters, and common conditions affecting digestion.

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