what is the name given to the mix of broken down food and water in the stomach and small intestine

Chapter 15. Animate being Diet and the Digestive Organisation

xv.one Digestive Systems

Learning Objectives

Past the end of this department, you volition be able to:

• Explicate the processes of digestion and absorption
• Compare and contrast unlike types of digestive systems
• Explain the specialized functions of the organs involved in processing food in the body
• Describe the means in which organs work together to digest food and absorb nutrients

Animals obtain their diet from the consumption of other organisms. Depending on their diet, animals can exist classified into the following categories: found eaters (herbivores), meat eaters (carnivores), and those that swallow both plants and animals (omnivores). The nutrients and macromolecules nowadays in nutrient are non immediately accessible to the cells. At that place are a number of processes that modify food within the animal body in order to brand the nutrients and organic molecules accessible for cellular function. Every bit animals evolved in complication of course and function, their digestive systems accept also evolved to adapt their various dietary needs.

Herbivores, Omnivores, and Carnivores

Herbivores are animals whose primary food source is constitute-based. Examples of herbivores, as shown in Figure fifteen.2 include vertebrates like deer, koalas, and some bird species, as well as invertebrates such as crickets and caterpillars. These animals take evolved digestive systems capable of handling large amounts of plant material. Herbivores can be further classified into frugivores (fruit-eaters), granivores (seed eaters), nectivores (nectar feeders), and folivores (leaf eaters).

Figure 15.2.  Herbivores, like this (a) mule deer and (b) monarch caterpillar, eat primarily plant material. (credit a: modification of work past Bill Ebbesen; credit b: modification of piece of work by Doug Bowman)

Carnivores are animals that consume other animals. The word carnivore is derived from Latin and literally ways "meat eater." Wild cats such equally lions, shown in Figure 35.3 a and tigers are examples of vertebrate carnivores, as are snakes and sharks, while invertebrate carnivores include ocean stars, spiders, and ladybugs, shown in Figure 15.three b . Obligate carnivores are those that rely entirely on fauna flesh to obtain their nutrients; examples of obligate carnivores are members of the cat family, such equally lions and cheetahs. Facultative carnivores are those that also consume non-beast food in improver to animal food. Note that in that location is no articulate line that differentiates facultative carnivores from omnivores; dogs would be considered facultative carnivores.

Figure fifteen.3.  Carnivores like the (a) lion eat primarily meat. The (b) ladybug is likewise a carnivore that consumes small insects called aphids. (credit a: modification of work by Kevin Pluck; credit b: modification of piece of work by Jon Sullivan)

Omnivores are animals that eat both found- and creature-derived nutrient. In Latin, omnivore means to eat everything. Humans, bears (shown in Figure 15.4 a ), and chickens are example of vertebrate omnivores; invertebrate omnivores include cockroaches and crayfish (shown in Figure 15.4 b ).

Figure 15.4.  Omnivores similar the (a) bear and (b) crayfish eat both plant and brute based nutrient. (credit a: modification of work by Dave Menke; credit b: modification of work by Jon Sullivan)

Invertebrate Digestive Systems

Animals have evolved dissimilar types of digestive systems to help in the digestion of the different foods they consume. The simplest example is that of a gastrovascular cavity and is establish in organisms with merely ane opening for digestion. Platyhelminthes (flatworms), Ctenophora (comb jellies), and Cnidaria (coral, jelly fish, and sea anemones) use this blazon of digestion. Gastrovascular cavities, as shown in Figure 15.5 a , are typically a bullheaded tube or crenel with only one opening, the "mouth", which likewise serves as an "anus". Ingested material enters the mouth and passes through a hollow, tubular cavity. Cells inside the crenel secrete digestive enzymes that pause downwardly the food. The food particles are engulfed by the cells lining the gastrovascular cavity.

The alimentary culvert, shown in Effigy fifteen.v b , is a more advanced system: it consists of i tube with a mouth at one end and an anus at the other. Earthworms are an example of an brute with an gastrointestinal tract. Once the nutrient is ingested through the mouth, information technology passes through the esophagus and is stored in an organ called the crop; so it passes into the gizzard where information technology is churned and digested. From the gizzard, the nutrient passes through the intestine, the nutrients are absorbed, and the waste is eliminated as feces, chosen castings, through the anus.

Figure xv.5.  (a) A gastrovascular cavity has a single opening through which food is ingested and waste is excreted, as shown in this hydra and in this jellyfish medusa. (b) An alimentary canal has 2 openings: a mouth for ingesting food, and an anus for eliminating waste, every bit shown in this nematode.

Vertebrate Digestive Systems

Vertebrates have evolved more circuitous digestive systems to adapt to their dietary needs. Some animals take a unmarried breadbasket, while others have multi-chambered stomachs. Birds have developed a digestive arrangement adapted to eating unmasticated food.

Monogastric: Single-chambered Tum

As the give-and-take monogastric suggests, this blazon of digestive arrangement consists of one ("mono") breadbasket sleeping accommodation ("gastric"). Humans and many animals accept a monogastric digestive system as illustrated in Figure fifteen.6 ab . The process of digestion begins with the rima oris and the intake of food. The teeth play an important role in masticating (chewing) or physically breaking down nutrient into smaller particles. The enzymes present in saliva also begin to chemically suspension downwards food. The esophagus is a long tube that connects the mouth to the stomach. Using peristalsis, or wave-like smooth muscle contractions, the muscles of the esophagus push button the nutrient towards the stomach. In lodge to speed upwards the deportment of enzymes in the tum, the stomach is an extremely acidic environment, with a pH between 1.5 and 2.5. The gastric juices, which include enzymes in the tum, act on the nutrient particles and continue the process of digestion. Farther breakdown of food takes place in the small intestine where enzymes produced by the liver, the small intestine, and the pancreas continue the process of digestion. The nutrients are absorbed into the claret stream across the epithelial cells lining the walls of the small intestines. The waste matter material travels on to the large intestine where water is absorbed and the drier waste material material is compacted into carrion; information technology is stored until it is excreted through the rectum.

Figure xv.six.
(a) Humans and herbivores, such as the (b) rabbit, accept a monogastric digestive system. However, in the rabbit the small intestine and cecum are enlarged to allow more time to assimilate plant material. The enlarged organ provides more surface surface area for absorption of nutrients. Rabbits digest their food twice: the showtime time food passes through the digestive system, it collects in the cecum, and and then it passes as soft feces chosen cecotrophes. The rabbit re-ingests these cecotrophes to further assimilate them.

Avian

Birds face special challenges when information technology comes to obtaining nutrition from nutrient. They exercise non have teeth and so their digestive system, shown in Figure 15.vii, must be able to procedure un-masticated nutrient. Birds have evolved a variety of pecker types that reverberate the vast variety in their nutrition, ranging from seeds and insects to fruits and nuts. Because most birds fly, their metabolic rates are high in order to efficiently procedure nutrient and keep their body weight low. The stomach of birds has two chambers: the proventriculus, where gastric juices are produced to digest the food before information technology enters the stomach, and the gizzard, where the food is stored, soaked, and mechanically ground. The undigested material forms food pellets that are sometimes regurgitated. Most of the chemical digestion and absorption happens in the intestine and the waste is excreted through the cloaca.

Figure fifteen.7.  The avian esophagus has a pouch, called a crop, which stores food. Food passes from the crop to the beginning of 2 stomachs, chosen the proventriculus, which contains digestive juices that break down nutrient. From the proventriculus, the food enters the 2nd stomach, called the gizzard, which grinds food. Some birds swallow stones or grit, which are stored in the gizzard, to help the grinding process. Birds practise not have divide openings to excrete urine and feces. Instead, uric acid from the kidneys is secreted into the big intestine and combined with waste matter from the digestive process. This waste is excreted through an opening called the cloaca.

Parts of the Digestive Organization

The vertebrate digestive arrangement is designed to facilitate the transformation of food matter into the nutrient components that sustain organisms.

Oral Cavity

The mouth, or mouth, is the point of entry of food into the digestive system, illustrated in Effigy 15.ix. The food consumed is broken into smaller particles by mastication, the chewing action of the teeth. All mammals take teeth and can chew their nutrient.

The all-encompassing chemic process of digestion begins in the mouth. Every bit food is beingness chewed, saliva, produced past the salivary glands, mixes with the nutrient. Saliva is a watery substance produced in the mouths of many animals. There are iii major glands that secrete saliva—the parotid, the submandibular, and the sublingual. Saliva contains mucus that moistens food and buffers the pH of the food. Saliva also contains immunoglobulins and lysozymes, which have antibacterial action to reduce tooth decay by inhibiting growth of some leaner. Saliva also contains an enzyme called salivary amylase that begins the process of converting starches in the food into a disaccharide called maltose. Another enzyme called lipase is produced by the cells in the tongue. Lipases are a class of enzymes that can pause downward triglycerides. The lingual lipase begins the breakup of fat components in the food. The chewing and wetting action provided by the teeth and saliva gear up the food into a mass called the bolus for swallowing. The tongue helps in swallowing—moving the bolus from the mouth into the pharynx. The pharynx opens to 2 passageways: the trachea, which leads to the lungs, and the esophagus, which leads to the breadbasket. The trachea has an opening called the glottis, which is covered past a cartilaginous flap called the epiglottis. When swallowing, the epiglottis closes the glottis and food passes into the esophagus and not the trachea. This arrangement allows nutrient to be kept out of the trachea.

Figure 15.nine.
Digestion of food begins in the (a) oral crenel. Food is masticated by teeth and moistened by saliva secreted from the (b) salivary glands. Enzymes in the saliva begin to assimilate starches and fats. With the assistance of the tongue, the resulting bolus is moved into the esophagus by swallowing. (credit: modification of piece of work by the National Cancer Institute)

Esophagus

The esophagus is a tubular organ that connects the oral fissure to the tummy. The chewed and softened food passes through the esophagus after being swallowed. The smoothen muscles of the esophagus undergo a serial of moving ridge like movements called peristalsis that push button the food toward the stomach, as illustrated in Figure fifteen.10. The peristalsis wave is unidirectional—information technology moves food from the mouth to the breadbasket, and reverse motility is not possible. The peristaltic movement of the esophagus is an involuntary reflex; information technology takes place in response to the act of swallowing.

Figure 15.10.  The esophagus transfers food from the mouth to the stomach through peristaltic movements.

A ring-like muscle called a sphincter forms valves in the digestive system. The gastro-esophageal sphincter is located at the stomach end of the esophagus. In response to swallowing and the force per unit area exerted by the bolus of food, this sphincter opens, and the bolus enters the stomach. When there is no swallowing action, this sphincter is close and prevents the contents of the tummy from traveling up the esophagus. Many animals take a true sphincter; nevertheless, in humans, at that place is no true sphincter, but the esophagus remains closed when at that place is no swallowing action. Acid reflux or "heartburn" occurs when the acidic digestive juices escape into the esophagus.

Tummy

A large part of digestion occurs in the stomach, shown in Effigy 15.11. The stomach is a saclike organ that secretes gastric digestive juices. The pH in the stomach is between 1.5 and 2.v. This highly acidic environment is required for the chemical breakdown of food and the extraction of nutrients. When empty, the stomach is a rather small organ; all the same, it can expand to up to 20 times its resting size when filled with food. This characteristic is especially useful for animals that need to eat when food is bachelor.

Figure 15.11.  The human stomach has an extremely acidic environment where most of the poly peptide gets digested. (credit: modification of work by Mariana Ruiz Villareal)

Which of the post-obit statements about the digestive arrangement is fake?

1. Chyme is a mixture of food and digestive juices that is produced in the stomach.
2. Food enters the large intestine earlier the small intestine.
3. In the small intestine, chyme mixes with bile, which emulsifies fats.
4. The breadbasket is separated from the small intestine by the pyloric sphincter.

The stomach is as well the major site for protein digestion in animals other than ruminants. Poly peptide digestion is mediated by an enzyme chosen pepsin in the tum bedchamber. Pepsin is secreted by the chief cells in the stomach in an inactive grade chosen pepsinogen. Pepsin breaks peptide bonds and cleaves proteins into smaller polypeptides; information technology too helps activate more pepsinogen, starting a positive feedback mechanism that generates more pepsin. Another cell blazon—parietal cells—secrete hydrogen and chloride ions, which combine in the lumen to form hydrochloric acid, the primary acidic component of the stomach juices. Hydrochloric acid helps to convert the inactive pepsinogen to pepsin. The highly acidic environment also kills many microorganisms in the nutrient and, combined with the action of the enzyme pepsin, results in the hydrolysis of poly peptide in the food. Chemical digestion is facilitated by the churning action of the stomach. Contraction and relaxation of polish muscles mixes the stomach contents about every 20 minutes. The partially digested food and gastric juice mixture is called chyme. Chyme passes from the tummy to the minor intestine. Further protein digestion takes place in the small intestine. Gastric emptying occurs within ii to six hours after a repast. Merely a pocket-sized amount of chyme is released into the small intestine at a time. The movement of chyme from the stomach into the small intestine is regulated by the pyloric sphincter.

When digesting protein and some fats, the stomach lining must be protected from getting digested by pepsin. There are two points to consider when describing how the stomach lining is protected. First, as previously mentioned, the enzyme pepsin is synthesized in the inactive form. This protects the primary cells, because pepsinogen does not accept the same enzyme functionality of pepsin. Second, the tummy has a thick mucus lining that protects the underlying tissue from the action of the digestive juices. When this mucus lining is ruptured, ulcers tin form in the stomach. Ulcers are open wounds in or on an organ caused past bacteria (Helicobacter pylori) when the mucus lining is ruptured and fails to reform.

Small-scale Intestine

Chyme moves from the tum to the small intestine. The small intestine is the organ where the digestion of protein, fats, and carbohydrates is completed. The modest intestine is a long tube-like organ with a highly folded surface containing finger-similar projections called the villi. The apical surface of each villus has many microscopic projections called microvilli. These structures, illustrated in Figure fifteen.12, are lined with epithelial cells on the luminal side and let for the nutrients to exist absorbed from the digested food and absorbed into the claret stream on the other side. The villi and microvilli, with their many folds, increase the surface area of the intestine and increase assimilation efficiency of the nutrients. Captivated nutrients in the blood are carried into the hepatic portal vein, which leads to the liver. There, the liver regulates the distribution of nutrients to the balance of the body and removes toxic substances, including drugs, booze, and some pathogens.

Figure 15.12.  Villi are folds on the small intestine lining that increase the expanse to facilitate the absorption of nutrients.

Which of the post-obit statements about the small intestine is false?

1. Absorbent cells that line the small intestine have microvilli, pocket-sized projections that increment surface area and aid in the absorption of food.
2. The inside of the small intestine has many folds, called villi.
3. Microvilli are lined with claret vessels too as lymphatic vessels.
4. The within of the modest intestine is called the lumen.

The man pocket-sized intestine is over 6m long and is divided into three parts: the duodenum, the jejunum, and the ileum. The "C-shaped," fixed part of the small intestine is called the duodenum and is shown in Effigy 15.11. The duodenum is separated from the stomach past the pyloric sphincter which opens to permit chyme to move from the tummy to the duodenum. In the duodenum, chyme is mixed with pancreatic juices in an element of group i solution rich in bicarbonate that neutralizes the acidity of chyme and acts as a buffer. Pancreatic juices also contain several digestive enzymes. Digestive juices from the pancreas, liver, and gallbladder, as well as from gland cells of the intestinal wall itself, enter the duodenum. Bile is produced in the liver and stored and full-bodied in the gallbladder. Bile contains bile salts which emulsify lipids while the pancreas produces enzymes that catabolize starches, disaccharides, proteins, and fats. These digestive juices break down the food particles in the chyme into glucose, triglycerides, and amino acids. Some chemical digestion of food takes place in the duodenum. Absorption of fatty acids also takes place in the duodenum.

The second function of the small intestine is called the jejunum, shown in Figure xv.11. Here, hydrolysis of nutrients is continued while most of the carbohydrates and amino acids are absorbed through the intestinal lining. The bulk of chemical digestion and food absorption occurs in the jejunum.

The ileum, also illustrated in Effigy 15.eleven is the last office of the small intestine and hither the bile salts and vitamins are absorbed into claret stream. The undigested food is sent to the colon from the ileum via peristaltic movements of the musculus. The ileum ends and the large intestine begins at the ileocecal valve. The vermiform, "worm-like," appendix is located at the ileocecal valve. The appendix of humans secretes no enzymes and has an insignificant role in amnesty.

Large Intestine

The large intestine, illustrated in Effigy 15.xiii, reabsorbs the h2o from the undigested nutrient cloth and processes the waste material. The human large intestine is much smaller in length compared to the small intestine but larger in diameter. It has three parts: the cecum, the colon, and the rectum. The cecum joins the ileum to the colon and is the receiving pouch for the waste material matter. The colon is home to many bacteria or "intestinal flora" that aid in the digestive processes. The colon tin can be divided into iv regions, the ascending colon, the transverse colon, the descending colon and the sigmoid colon. The main functions of the colon are to extract the water and mineral salts from undigested nutrient, and to store waste matter material. Carnivorous mammals have a shorter large intestine compared to herbivorous mammals due to their diet.

Rectum and Anus

The rectum is the terminal end of the large intestine, equally shown in Figure 15.13. The primary role of the rectum is to shop the feces until defecation. The feces are propelled using peristaltic movements during elimination. The anus is an opening at the far-terminate of the digestive tract and is the exit point for the waste material material. Two sphincters betwixt the rectum and anus control elimination: the inner sphincter is involuntary and the outer sphincter is voluntary.

Accessory Organs

The organs discussed above are the organs of the digestive tract through which food passes. Accessory organs are organs that add secretions (enzymes) that catabolize food into nutrients. Accessory organs include salivary glands, the liver, the pancreas, and the gallbladder. The liver, pancreas, and gallbladder are regulated past hormones in response to the food consumed.

The liver is the largest internal organ in humans and information technology plays a very important function in digestion of fats and detoxifying blood. The liver produces bile, a digestive juice that is required for the breakdown of fatty components of the nutrient in the duodenum. The liver also processes the vitamins and fats and synthesizes many plasma proteins.

The pancreas is some other of import gland that secretes digestive juices. The chyme produced from the tummy is highly acidic in nature; the pancreatic juices contain high levels of bicarbonate, an alkali that neutralizes the acidic chyme. Additionally, the pancreatic juices contain a large diverseness of enzymes that are required for the digestion of protein and carbohydrates.

The gallbladder is a small organ that aids the liver by storing bile and concentrating bile salts. When chyme containing fatty acids enters the duodenum, the bile is secreted from the gallbladder into the duodenum.

Summary

Dissimilar animals have evolved different types of digestive systems specialized to encounter their dietary needs. Humans and many other animals take monogastric digestive systems with a single-chambered stomach. Birds accept evolved a digestive system that includes a gizzard where the food is crushed into smaller pieces. This compensates for their disability to masticate. Ruminants that consume large amounts of constitute material have a multi-chambered stomach that digests roughage. Pseudo-ruminants accept similar digestive processes as ruminants only do not have the four-compartment tummy. Processing nutrient involves ingestion (eating), digestion (mechanical and enzymatic breakup of large molecules), absorption (cellular uptake of nutrients), and elimination (removal of undigested waste as feces).

Many organs work together to digest nutrient and blot nutrients. The oral fissure is the betoken of ingestion and the location where both mechanical and chemic breakup of food begins. Saliva contains an enzyme called amylase that breaks downward carbohydrates. The food bolus travels through the esophagus past peristaltic movements to the stomach. The tum has an extremely acidic environment. An enzyme called pepsin digests poly peptide in the breadbasket. Further digestion and absorption take place in the small intestine. The big intestine reabsorbs h2o from the undigested food and stores waste product until elimination.

Exercises

1. Which of the following statements most the digestive system is false?
   1. Chyme is a mixture of food and digestive juices that is produced in the tum.
   2. Nutrient enters the big intestine before the minor intestine.
   3. In the small intestine, chyme mixes with bile, which emulsifies fats.
   4. The tummy is separated from the pocket-sized intestine by the pyloric sphincter.
2. Which of the following statements about the small intestine is false?
   1. Absorptive cells that line the small-scale intestine have microvilli, small projections that increment surface expanse and aid in the absorption of food.
   2. The inside of the small intestine has many folds, called villi.
   3. Microvilli are lined with claret vessels likewise every bit lymphatic vessels.
   4. The within of the pocket-sized intestine is chosen the lumen.
3. Which of the following is a pseudo-ruminant?
   1. cow
   2. squealer
   3. crow
   4. horse
4. Which of the following statements is untrue?
   1. Roughage takes a long time to digest.
   2. Birds swallow big quantities at one time so that they can fly long distances.
   3. Cows practise non have upper teeth.
   4. In pseudo-ruminants, roughage is digested in the cecum.
5. The acidic nature of chyme is neutralized by ________.
   1. potassium hydroxide
   2. sodium hydroxide
   3. bicarbonates
   4. vinegar
6. The digestive juices from the liver are delivered to the ________.
   1. breadbasket
   2. liver
   3. duodenum
   4. colon
7. How does the polygastric digestive system aid in digesting roughage?
8. How practice birds digest their food in the absence of teeth?
9. What is the function of the accessory organs in digestion?
10. Explain how the villi and microvilli aid in absorption.

Answers

1. B
2. C
3. D
4. B
5. C
6. C
7. Animals with a polygastric digestive system have a multi-chambered stomach. The 4 compartments of the tummy are chosen the rumen, reticulum, omasum, and abomasum. These chambers contain many microbes that break down the cellulose and ferment the ingested food. The abomasum is the "true" tummy and is the equivalent of a monogastric stomach chamber where gastric juices are secreted. The four-compartment gastric chamber provides larger space and the microbial support necessary for ruminants to digest plant textile.
8. Birds have a stomach chamber chosen a gizzard. Hither, the food is stored, soaked, and ground into finer particles, often using pebbles. Once this process is complete, the digestive juices accept over in the proventriculus and continue the digestive process.
9. Accessory organs play an of import role in producing and delivering digestive juices to the intestine during digestion and absorption. Specifically, the salivary glands, liver, pancreas, and gallbladder play important roles. Malfunction of whatsoever of these organs tin pb to disease states.
10. The villi and microvilli are folds on the surface of the small intestine. These folds increase the surface expanse of the intestine and provide more than expanse for the absorption of nutrients.

Glossary

alimentary canal: tubular digestive system with a oral fissure and anus
anus: exit signal for waste textile
bile: digestive juice produced by the liver; of import for digestion of lipids
bolus: mass of food resulting from chewing action and wetting by saliva
carnivore: animal that consumes animal flesh
chyme: mixture of partially digested food and stomach juices
digestion: mechanical and chemical break downwardly of nutrient into pocket-size organic fragments
duodenum: first part of the modest intestine where a big role of digestion of carbohydrates and fats occurs
endocrine system: system that controls the response of the various glands in the body and the release of hormones at the appropriate times
esophagus: tubular organ that connects the mouth to the stomach
essential food: food that cannot exist synthesized by the body; it must exist obtained from nutrient
gallbladder: organ that stores and concentrates bile
gastric inhibitory peptide: hormone secreted past the small intestine in the presence of fatty acids and sugars; information technology likewise inhibits acid production and peristalsis in order to slow down the rate at which food enters the small intestine
gastrin: hormone which stimulates hydrochloric acid secretion in the stomach
gastrovascular cavity: digestive system consisting of a unmarried opening
gizzard: muscular organ that grinds nutrient
plant eater: animal that consumes strictly plant diet
ileum: last part of the modest intestine; connects the modest intestine to the large intestine; important for assimilation of B-12
ingestion: human activity of taking in food
jejunum: second part of the small intestine
lactase: enzyme that breaks downwards lactose into glucose and galactose
large intestine: digestive arrangement organ that reabsorbs h2o from undigested textile and processes waste product
lipase: enzyme that chemically breaks down lipids
liver: organ that produces bile for digestion and processes vitamins and lipids
maltase: enzyme that breaks downward maltose into glucose
mineral: inorganic, elemental molecule that carries out important roles in the body
monogastric: digestive system that consists of a single-chambered stomach
omnivore: animal that consumes both plants and animals
pancreas: gland that secretes digestive juices
pepsinogen: inactive form of pepsin
pepsin: enzyme found in the tummy whose main role is protein digestion
peristalsis: wave-like movements of muscle tissue
proventriculus: glandular office of a bird'south stomach
rectum: area of the torso where feces is stored until elimination
roughage: component of nutrient that is depression in free energy and loftier in fiber
ruminant: animal with a stomach divided into 4 compartments
salivary amylase: enzyme found in saliva, which converts carbohydrates to maltose
small intestine: organ where digestion of protein, fats, and carbohydrates is completed
somatostatin: hormone released to finish acid secretion when the stomach is empty
sphincter: ring of muscle that controls movement of materials throughout the digestive tract
breadbasket: saclike organ containing acidic digestive juices
villi: folds on the inner surface of the small intestine whose part is to increase absorption expanse
vitamin: organic substance necessary in pocket-size amounts to sustain life

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