the digestive system Flashcards
What is chemical digestion?
Chemical digestion are enzymes that break down complex compounds into simple compounds (breaking into smaller pieces chemically).
What is mechanical digestion?
Mechanical digestion is the process of using your body (mouth, teeth, tongue) to physically break down solid foods into smaller pieces.
What are the main roles of the digestive system?
Ingestion - Absorbing nutrients into the body and the process of taking food into the mouth by eating or drinking them.
Digestion - food is broken down into a substance chemically through enzymes in your saliva, which is suitable for absorption in the body.
Absorption - Taking the digested substance into the internal environment of the cells in the digestive tract.
Egestion - The removal of wastes from the body.
Lest complex to most complex - organs, tissues, cells, systems.
Cells - basic unit of life
Tissues - group of cells
Organ - group of tissues
System - group of organs
What are villi’s and micro-villi?
Villi’s are tiny finger-like projections that are found in the lining of the small intestine. It has a high SA:V ratio as it has grooves for an effective absorption of nutrients.
Micro-villi’s are hair-like projections that on the surface of the villi, found in the small intestine. Also has a high SA:V ratio.
What is the digestive system?
The digestive system is responsible for the digestion of food and the absorption of nutrients.
Elementary canal is hollow.
Accessory canal is not hollow, is solid.
What is the function of the mouth?
The mouth has 3 major salivary glands - water, mucus and amylase. Amylase is a enzyme that breaks down starchy food into glucose as wells as carbohydrates.
In the mouth, there is teeth to break foods into smaller pieces and tongue to push food down to your throat.
What are the functions of each teeth?
Incisors - used for cutting and cropping.
Canines - used to hold and tear food.
Premolars and molars - used for grinding and chewing.
How can you tell by looking at someone’s teeth if they are a Carnivore, Herbivore or Omnivore?
Herbivores - have incisors to cut food, are often in the lower jaw. Large molars to grind down food.
Carnivores - have smaller incisors and large, sharp canines to grip and tear meat off of bones.
Omnivores - have all types of teeth including molars to grind food, incisors to cut down foods such as plants and canines to hold and tear food.
What is the esophagus?
The esophagus is a muscular tube that connects the pharynx to the stomach. This is for the process of swallowing and getting a bolus (ball of food) down to your stomach. The esophagus uses peristaltic movement to contract food down without stomach acid rising up.
What is the stomach?
The stomach is an organ that releases acids and enzymes to digest your food. Mechanical digestion is used through muscles twist and churn to mix acids with enzymes. Chemical digestion is used through hydrochloric acid and pepsin as they break down food.
What is the small intestine?
The small intestine absorbs nutrients into the bloodstream. The 3 main parts of the small intestine, duodenum, jejunum and ileum.
Duodenum - receives acidic chyme (digested food) from the stomach and is neutralised by bicarbonate.
Jejunum - where most nutrients are absorbed into the bloodstream.
Ileum - Absorbs various vitamins and the remaining nutrients from the chyme. Villi and Micro villi are on the lining of the small intestine.
What is the large intestine?
The three main parts of the large intestine is the Ascending colon, Transverse colon and the Descending colon. The function is to extract moisture from the chyme before the removal from the body.
What are accessory organs?
Accessory organs are organs that help with digestion but is not part of the digestive tract.
What is the pancreas?
The pancreas releases bicarbonate to neutralise the acid from the stomach. It releases enzymes to break down peptides into amino acids and carbohydrates into small sugars through chemical digestion. Insulin is produced from the beta cells inside the pancreas.
