Compendium 3

The primary adaptations include extensive villi and microvilli, as well as the folded structure of the intestinal wall.

The liver produces bile, which aids in the emulsification of fats and detoxifies substances absorbed from the digestive tract.

The gallbladder stores and concentrates bile produced by the liver until it is needed in the small intestine.

<p>The large intestine absorbs water and electrolytes, contributing to the formation of solid waste, or feces.</p> Signup and view all the answers

<p>Pancreatic enzymes break down carbohydrates, proteins, and fats in chyme, facilitating nutrient absorption in the small intestine.</p> Signup and view all the answers

<p>Chyme is a thick liquid formed by the mixing of food with gastric juices in the stomach through churning.</p> Signup and view all the answers

<p>The small intestine consists of three divisions: the duodenum, jejunum, and ileum, and is about 6 meters long.</p> Signup and view all the answers

<p>The pyloric sphincter regulates the passage of chyme from the stomach to the duodenum.</p> Signup and view all the answers

<p>The small intestine primarily absorbs nutrients and minerals from food.</p> Signup and view all the answers

<p>The liver produces bile, which helps emulsify fats for digestion.</p> Signup and view all the answers

<p>The gall bladder stores and concentrates bile until it is needed for fat digestion.</p> Signup and view all the answers

<p>The large intestine primarily absorbs water and electrolytes from indigestible food matter.</p> Signup and view all the answers

<p>Pancreatic enzymes break down carbohydrates, proteins, and fats into smaller molecules for absorption.</p> Signup and view all the answers

<p>Chyme is formed by the mixing of food with gastric juices in the stomach, turning it into a semi-liquid substance.</p> Signup and view all the answers

<p>Peristalsis moves food through the digestive tract by rhythmic contractions of the smooth muscle.</p> Signup and view all the answers

<p>Salivary glands produce saliva that moistens food, begins the digestion of carbohydrates, and protects the oral cavity.</p> Signup and view all the answers

<p>The gastro-oesophageal sphincter prevents the backflow of stomach contents into the oesophagus.</p> Signup and view all the answers

<p>The uvula prevents food and drink from entering the nasopharynx during swallowing.</p> Signup and view all the answers

<p>The three parts of the small intestine are the duodenum, jejunum, and ileum, primarily responsible for nutrient absorption.</p> Signup and view all the answers

<p>The liver produces bile for digestion and detoxification, while the gallbladder stores and concentrates bile until needed.</p> Signup and view all the answers

<p>The large intestine primarily absorbs water, electrolytes, and some vitamins, helping to compact waste into feces.</p> Signup and view all the answers

<p>Pancreatic enzymes break down carbohydrates, proteins, and fats, facilitating their absorption in the small intestine.</p> Signup and view all the answers

<p>Chyme is formed in the stomach when food is churned and mixed with gastric juices, turning solid food into a semi-liquid mixture.</p> Signup and view all the answers

<p>The mesentery proper connects the small intestines to the posterior body wall and provides blood supply.</p> Signup and view all the answers

<p>The mucosa is the innermost layer of the digestive tract, responsible for secreting mucus and coming into direct contact with food.</p> Signup and view all the answers

<p>The muscularis layer contains circular and longitudinal muscle layers.</p> Signup and view all the answers

<p>Mastication, or chewing, breaks food into smaller particles to enhance the surface area for chemical digestion.</p> Signup and view all the answers

<p>Elimination involves the removal of waste products from the body, primarily in the form of feces during defecation.</p> Signup and view all the answers

<p>Plicae circulares are circular folds found in the wall of the small intestine.</p> Signup and view all the answers

<p>Villi are finger-like folds that contain capillaries and lacteals, while microvilli are small extensions of epithelial cells that further increase surface area for absorption.</p> Signup and view all the answers

<p>The liver produces bile, which helps to emulsify and break down large lipids into smaller ones.</p> Signup and view all the answers

<p>The gall bladder stores and concentrates bile, releasing it into the duodenum via the common bile duct.</p> Signup and view all the answers

<p>Phospholipids are the components of plasma membranes that are modified to form bile salts.</p> Signup and view all the answers

<p>Approximately 9L of water enters the digestive tract daily, and about 99% is absorbed.</p> Signup and view all the answers

<p>The pancreas produces digestive enzymes like lipase, pancreatic amylase, and trypsin.</p> Signup and view all the answers

<p>The large intestine absorbs water and NaCl from the chyme, reabsorbing approximately 90% of its content.</p> Signup and view all the answers

<p>The two types of vitamins are fat-soluble (K, E, D, A) and water-soluble (B, C), and they are essential for normal metabolism.</p> Signup and view all the answers

<p>Excessive Vitamin A can cause birth defects during pregnancy, while too much Vitamin D alters calcium metabolism.</p> Signup and view all the answers

<p>Chyme is the semi-liquid mass of partially digested food that enters the small intestine from the stomach.</p> Signup and view all the answers

<p>Water facilitates the active transport of minerals, such as sodium, potassium, calcium, magnesium, and phosphate, across the intestinal wall.</p> Signup and view all the answers

<p>Bacteria in the large intestine synthesize vitamins B and K and help in the fermentation of undigested materials.</p> Signup and view all the answers

<p>The defecation reflex is triggered by rectal distension when the rectum fills with feces.</p> Signup and view all the answers

<p>Digestion involves mechanical and chemical breakdown of food in the mouth, stomach, and small intestine, followed by absorption in the small and large intestines.</p> Signup and view all the answers

<p>It provides stability by holding everything in place and connecting organs together.</p> Signup and view all the answers

<p>Peristalsis moves food forward through coordinated muscle contractions, while segmentation mixes food and aids in nutrient absorption.</p> Signup and view all the answers

<p>The visceral peritoneum covers the organs, while the parietal peritoneum lines the internal surfaces of the body wall.</p> Signup and view all the answers

<p>Salivary glands produce saliva that moistens food, begins digestion of carbohydrates, and protects the oral cavity.</p> Signup and view all the answers

<p>The epiglottis prevents food and drink from entering the trachea during swallowing.</p> Signup and view all the answers

<p>Teeth have different types (incisors, canines, premolars, molars) that are specialized for cutting, tearing, and grinding food.</p> Signup and view all the answers

<p>The greater omentum connects the stomach to the transverse colon, while the lesser omentum connects the stomach to the liver and diaphragm.</p> Signup and view all the answers

<p>The uvula prevents food and drink from entering the nasopharynx during swallowing.</p> Signup and view all the answers

<p>Non-essential amino acids are synthesized by the body from essential amino acids and are crucial for various functions.</p> Signup and view all the answers

<p>Complete proteins contain all nine essential amino acids, while incomplete proteins lack one or more of these essential amino acids.</p> Signup and view all the answers

<p>Bile emulsifies lipids, breaking them down into smaller droplets for easier digestion by lipase.</p> Signup and view all the answers

<p>Triglycerides serve as a major energy source and are stored for later use in adipose tissue and the liver.</p> Signup and view all the answers

<p>Saturated fats have no double bonds in their carbon chain, leading to a solid state at room temperature, while unsaturated fats have one or more double bonds, making them liquid.</p> Signup and view all the answers

<p>Glycogen is digested by salivary amylase in the oral cavity and by pancreatic amylase in the duodenum.</p> Signup and view all the answers

<p>Sucrase digests the disaccharide sucrose in the intestine.</p> Signup and view all the answers

<p>Glucose is absorbed into the blood through villi and microvilli in the intestine and transported to the liver via the hepatic portal vein.</p> Signup and view all the answers

<p>Glucose is primarily used to produce ATP, which provides energy for bodily functions.</p> Signup and view all the answers

<p>Proteins are composed of carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur.</p> Signup and view all the answers

<p>The side group of each amino acid is what differentiates them.</p> Signup and view all the answers

<p>Excess glucose is stored as glycogen in the liver or muscles, and any remaining excess is converted into fat.</p> Signup and view all the answers

<p>Essential amino acids cannot be synthesized by the body and must be obtained through diet.</p> Signup and view all the answers

<p>Carbohydrates, particularly sugars, are integral components of DNA, RNA, ATP, glycoproteins, and glycolipids.</p> Signup and view all the answers

<p>Amino acids link together through peptide bonds to form peptides, polypeptides, and ultimately proteins.</p> Signup and view all the answers

<p>The swallowing reflex is initiated when the bolus touches receptors in the oropharynx.</p> Signup and view all the answers

<p>The stomach serves as the holding point for food and churns it into chyme.</p> Signup and view all the answers

<p>The stomach contains a thick mucus layer that shields the epithelial cells from acid.</p> Signup and view all the answers

<p>The pyloric sphincter regulates the passage of chyme from the stomach to the duodenum.</p> Signup and view all the answers

<p>The small intestine has extensive villi and microvilli that increase its surface area.</p> Signup and view all the answers

<p>The jejunum is primarily responsible for the absorption of nutrients.</p> Signup and view all the answers

<p>Rugae are folds in the stomach wall that allow it to stretch after eating.</p> Signup and view all the answers

<p>Peristaltic contractions are responsible for moving the bolus down the esophagus.</p> Signup and view all the answers

<p>The duodenum curves around the pancreas and mixes chyme with digestive enzymes.</p> Signup and view all the answers

<p>Enzymes are protein catalysts that increase the rate of chemical reactions without being permanently changed. Their primary function is to facilitate various biochemical reactions by binding to specific substrates at their active sites.</p> Signup and view all the answers

<p>The six classes of nutrients are carbohydrates (e.g., sugars), proteins (e.g., amino acids), lipids (e.g., triglycerides), vitamins (e.g., vitamin C), minerals (e.g., calcium), and water.</p> Signup and view all the answers

<p>Essential nutrients are those that must be obtained from the diet because the body cannot synthesize them. In contrast, non-essential nutrients can be produced by the body itself.</p> Signup and view all the answers

<p>Carbohydrates, proteins, and lipids are classified as organic macronutrients because they all contain carbon. Carbohydrates consist of carbon, hydrogen, and oxygen; proteins are made of amino acids containing carbon; and lipids are largely composed of carbon and hydrogen chains.</p> Signup and view all the answers

<p>Monosaccharides are single sugar units (e.g., glucose), disaccharides are composed of two monosaccharides (e.g., sucrose), and polysaccharides consist of long chains of monosaccharides (e.g., glycogen).</p> Signup and view all the answers

<p>Glycogen serves as a stored form of glucose in humans, primarily found in the liver and muscles. It provides a readily available source of energy when the body requires it.</p> Signup and view all the answers

<p>Dietary fiber, primarily from cellulose found in plants, is important because it aids in gastrointestinal health by promoting regular bowel movements and preventing constipation.</p> Signup and view all the answers

<p>Carbohydrates should comprise 45-65% of daily kilocalories, lipids should be 20-35%, and proteins should constitute 10-35% of total daily kilocalories.</p> Signup and view all the answers

<p>Humans can digest and break down starch for energy, whereas cellulose cannot be digested and serves as dietary fiber. This difference highlights the role of different carbohydrates in human nutrition.</p> Signup and view all the answers

<p>Vitamins and minerals are taken into the body without digestion, while macronutrients like carbohydrates, proteins, and lipids require digestion to be absorbed. This distinction is crucial for understanding nutrient absorption.</p> Signup and view all the answers