Digestive system a level biology. Human Digestive System 2022-11-16

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The digestive system is a complex and vital system in the human body that is responsible for the breakdown and absorption of nutrients from the food we eat. It is made up of a series of organs and structures that work together to process and transport food through the body.

The digestive process begins in the mouth, where food is mechanically broken down by the teeth and mixed with saliva. Saliva contains an enzyme called amylase, which begins the chemical digestion of carbohydrates. The food is then passed down the esophagus through a process called peristalsis, which involves the contraction and relaxation of muscles in the walls of the esophagus.

The next stop in the digestive process is the stomach, which is a muscular sac that mixes and grinds the food with stomach acid and enzymes. Stomach acid, also known as hydrochloric acid, helps to kill bacteria and further breaks down the food. The stomach also releases hormones that help to regulate the digestive process and signal to the brain when we are full.

After being processed in the stomach, the partially digested food moves into the small intestine. The small intestine is a long, narrow tube that is lined with tiny finger-like projections called villi. These villi greatly increase the surface area of the intestine, allowing for more efficient absorption of nutrients. The small intestine also receives bile from the liver and enzymes from the pancreas, which aid in the digestion of fats, proteins, and carbohydrates.

As the partially digested food moves through the small intestine, the nutrients are absorbed into the bloodstream and transported to the liver for storage or further processing. Any undigested material and waste products are passed on to the large intestine, which absorbs water and electrolytes from the remaining material and forms the feces. The feces are then stored in the rectum until they are eliminated through the anus.

The digestive system is a vital part of the human body that plays a crucial role in maintaining overall health and well-being. It is important to maintain a healthy diet and lifestyle in order to support the proper functioning of the digestive system and ensure the proper absorption of nutrients.

The Digestive System

digestive system a level biology

This reserve of iron is again used to form haemoglobin in new R. When chyme containing fatty acids enters the duodenum, the bile is secreted from the gallbladder into the duodenum. Bile juice helps in splitting the fat into small particles and thus helps the action of lipase for its digestion. Fungi secrete digestive enzymes carbohydrases, proteases and lipases into the material that surrounds them and then absorb the soluble products sugars, amino acids, etc. The liver also processes the absorbed vitamins and fatty acids and synthesizes many plasma proteins. It mixes the food well with the salivary juice by moving it into different direction.

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Digestive System

digestive system a level biology

Inside the curve, the head of the pancreas is encircled. It acts upon undigested protein foods and peptones and converts them into polypeptides. The food bolus travels through the esophagus by peristaltic movements to the stomach. They eat a lot of plant material and roughage. Emulsification is a process in which large lipid globules are broken down into several small lipid globules. A low pH 1.

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What do digestive enzymes do a level biology? [Fact Checked!]

digestive system a level biology

Where are digestive enzymes produced? An anti-anaemic factor is formed in the stomach. Hydrochloric acid helps to convert the inactive pepsinogen to pepsin. The peristalsis wave is unidirectional: it moves food from the mouth to the stomach; reverse movement is not possible. For the digestive system, its muscular walls function in the process of swallowing, and it serves as a pathway for the movement of food from the mouth to the esophagus. This duct is extended from left to right in the center of the gland and through the head of the pancreas enters the Duodenum at the Ampulla of Vater.

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34.10: Digestive System Processes

digestive system a level biology

Fats are also required in the diet to aid the absorption of fat-soluble vitamins and the production of fat-soluble hormones. The teeth chew the food and breaks into small pieces while the tongue thoroughly mixes the saliva with the food. Most absorption of amino acids occurs in the jejunum; there is a lesser contribution from the ileum. Examples of herbivores: Herbivores, such as this a mule deer and b monarch caterpillar, eat primarily plant material. The smaller molecules are absorbed into the blood stream through the epithelial cells lining the walls of the small intestine. Generalized animal digestive system: This diagram shows a generalized animal digestive system, detailing the different organs and their functions. It is here that bile salts and vitamins are absorbed into blood stream.

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Digestive Systems

digestive system a level biology

The shape is like a horse-shoe. They are stored as triglycerides in adipose fat tissue. These are all parts of the large intestine. The complex foods like carbohydrates, proteins and fats are converted into glucose, amino acids and fatly acids respectively by the action of digestive enzymes. This acidity kills microorganisms, breaks down food tissues, and activates digestive enzymes. The duodenal opening of the ampulla is controlled by the hepatopancreatic sphincter of Oddi.


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The Human Digestive System

digestive system a level biology

Accessory organs include salivary glands, the liver, the pancreas, and the gallbladder. The internal surface area is increased enormously by three levels of folding: large folds of the mucosa, villi, and microvilli. The ileum is the last part of the small intestine. The gastric juice is poured into the cavity of the stomach and mixed with the food. The upper gastrointestinal tract includes the oral cavity, esophagus, and stomach.

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18: Digestive System

digestive system a level biology

Digestion in Stomach: After the food enters the stomach for some fifteen to twenty minutes, the action of saliva continues that is conversion of starchy food to maltose. The bolus passes through the esophagus, a long and relatively narrow tube made of smooth muscle that traverses the thoracic cavity. Provided by: OpenStax CNX. Further breakdown of food takes place in the small intestine where bile produced by the liver, and enzymes produced by the small intestine and the pancreas, continue the process of digestion. Carbohydrate digestion is completed in the small intestine. Although the Latin term omnivore literally means "eater of everything", omnivores cannot really eat everything that other animals eat.

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Quiz: Digestive System

digestive system a level biology

It is the middle portion of the small intestine. It helps to prevent damage to the mucous membrane by rough or abrasive foodstuffs. Functions: The teeth are essential for efficient mastication. Water-soluble vitamins can be directly absorbed into the bloodstream from the intestine. This keeps in the stomach longer so that pepsin can digest it. There are two stages of digestion; physical breakdown and chemical absorption. These muscles are arranged in longitudinal, diagonal and circular layers.

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11.2 Digestive System

digestive system a level biology

Together, they enable the chylomicron to move in an aqueous environment without exposing the lipids to water. Salivary juice secreted from salivary Glands in the mouth act upon Carbohydrate foods. Digestion is the breaking down of chemicals in the body to a form that can be absorbed and used. An interesting feature of the ruminants' mouth is that they do not have upper incisor teeth. Which enzyme digests protein in the stomach? Fatly acids get phosphorylated and these get transported across the lacteals as phospholipids. Saliva dissolves the food particles, which stimulate the taste buds.


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BiologyMad A

digestive system a level biology

These hormones are: 1. What enzyme breaks carbohydrates? It absorbs water and consists of bacteria symbiotic that support the breakdown of wastes to fetch small nutrients. Some animals have a single stomach, while others have multi-chambered stomachs. The organs that make up the GI tract include the mouth, the esophagus, the stomach, the small intestine, and the large intestine. The conversion of the food consumed to the nutrients required is a multi-step process involving digestion and absorption. The pancreas secretes this hormone to lower blood glucose when levels get too high. At the cellular level, the biological molecules necessary for animal function are amino acids, lipid molecules, nucleotides, and simple sugars.

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