7.2 The human digestive system Flashcards
digestive system
the group of organs that carries out digestion of food
liver
a large, dark red organ that carries out many different functions, including production of bile and the regulation of blood glucose concentration
pancreas
a creamy-white organ lying close to the stomach, which secretes pancreatic juice; it also secretes the hormones insulin and glucagon, which are involved in the control of blood glucose concentration
absorbed
soaked up; nutrients are absorbed from the alimentary canal into the blood, through the walls of the small intestine
ingestion
the taking of food and drink into the body
digestion
the breakdown of food
physical digestion
the breakdown of food into smaller pieces without making any chemical changes to the molecules in the food
chemical digestion
the breakdown of large molecules in food into smaller molecules so that they can be absorbed
absorption
the movement of nutrients from the alimentary canal into blood
assimilation
the uptake and use of nutrients by cells
egestion
the removal of undigested food from the body as faeces
anus
the exit from the alimentary canal, through which faeces are removed
sphincter muscle
rings of muscle that can contract to close a tube
lubricated
made smooth and slippery, to reduce friction
mucus
a smooth, viscous fluid secreted by many different organs in the body
goblet cells
cells found in the lining ( epithelium) of the respiratory passages and digestive system, which secrete mucus
salivary glands
groups of cells close to the mouth, which secrete saliva into the salivary ducts
oesophagus
the tube leading from the mouth to the stomach
trachea
the tube through which air travels to the lungs: it has rings of cartilage in its walls, to support it.
stomach
A wide part of the alimentary canal, in which food can be stored for a while and where the digestion of protein begins
lumen
the space in the centre of a tube, through which a substance can move
duodenum
the first part of the small intestine, into which the pancreatic duct and bile duct empty fluids
small intestine
a long, narrow part of the alimentary canal, consisting of the duodenum and ileum
colon
the first part of the large intestine
ileum
the second part of the small intestine; most absorption takes place here
pancreatic duct
the tube that carries pancreatic fluid from the pancreas to the duodenum
large intestine
a relatively wide part of the alimentary canal consisting of the colon and rectum
rectum
the second part of the large intestine, where faeces are produced and stored
bile
an alkaline fluid produced by the liver, which helps with fat digestion
gall bladder
a small organ that stores bile, before the bile is released into the duodenum
bile duct
the tube that carries bile from the gall bladder to the duodenum