Human Digestive System Vocabulary

Vocabulary flashcards covering the components and functions of the human digestive system, including organ descriptions, digestive processes, and tooth types.

peristalsis

rhythmical muscular contractions that move food through the alimentary canal

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 pen 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 the 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 muscles

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 ducts ,which mouth, which secrete saliva into the salivary

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 substances 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 duodenumenamel

enamel

the very strong material that covers the surface of a tooth

dentine

a living tissue that lies just beneath the enamel of a tooth

cement

the material that holds a tooth in the gum

incisors

chisel-shaped teeth at the front of the mouth, used for biting off pieces of food

canines

pointed teeth at either side of the incisors, used in a similar way to incisors, in carnivores, they are used for killing prey

premolars

teeth with broad, ridged surfaces, found between the canines and molars; they are used for grinding food to increase its surface area

molars

teeth similar to premolars but usually larger, with broad, ridged surfaces, found towards the back of the mouth; they are used for grinding food to increase its surface area

maltose

a reducing sugar made of two glucose molecules joined together

epithelium

a tissue that covers a surface in an animal; for example, an epithelium covers the inside of the wall of the human alimentary canal

pepsin

a protease enzyme secreted in gastric juice; it has an optimum $pH$ of 2

gastric juice

a liquid secreted by the walls of the stomach; it contains pepsin and hydrochloric acid

trypsin

a protease enzyme secreted by the pancreas; it works in the duodenum

emulsifies

breaks down large drops of fat or oil into smaller droplets, increasing their surface area and allowing them to mix with watery liquids

villi (singular: villus)

very small finger-like projections that line the inner surface of the small intestine, greatly increasing its surface area

microvilli

tiny folds on the surfaces of the cells of the epithelium of the villi in the small intestine

hepatic portal vein

the blood vessel that carries blood from the small intestine to the liver

lacteals

small vessels that absorb fatty acids and glycerol in the small intestine; their contents are eventually emptied into the blood