Flashcards in Organisation Deck (96)
What is a tissue
a group of cells working together to complete a specific function
What is an organ
a group of tissues working together to complete a specific function
What is an organ system?
a group of organs working together to complete a specific function
What are the three main nutrients gained from foods?
-all these are large molecules. They have to be digested as they can't be absorbed into the blood stream
What is digestion?
The break down of large food molecules into smaller ones via digestion so it can be absorbed into the blood stream
What is the first stage of the digetive system?
-first food is chewed in the mouth
-amylase in the saliva begin to digest starch into smaller sugar molecules
-the saliva helps make the food into a bulas, so the food can pass down into the oesphagus
What is the second stage of the digestive system
-the oesphagus squeezes the food down the oesphagues into the stomach
-the food passes into the stomach. This is where the digestion of proteins begins. There is also HydroCloric acid in the stomach. This helps to break down the proteins.
-There is a churning action in the stomach that turns the food into a fluid, increasing surface area for enzymes to digest
What is the third stage of the digestive system
-the fluid passes into the digestive system.
-the pancreaus and liver release chemcials into the small intestine.
-the pancreus releases amylase, lipase and protease that continue digestion of starch and protein.
-the liver releases bile and speeds up the digestion of lipids as it neutrilises acid from the stomach.
What is the fourth stage to the digestive system
-the walls of the small intestine release protease and lipease to continue the breakdown of protein and lipids. as the food molecules are smaller, some are absorbed into the blood stream by active transport or diffusion
What is the fith stage of the digestive system
-the fluid makes its way through the large intestine, where the water is absorbed into the bloodstream
-feeces are released from the body
What are the products of the digestive system used for
-glucose produced is used in respiration
What are enzymes?
-large protein molecules that speed up reactions
What is the active site
-This is where the substrate (molecule breaking down) locks on to
How is the substrate described to attach to the active site?
-like a lock and key
-only some elements are able to break down with the enzymes
What enzyme breaks down proteins?
What are proteins
-these are long chains of chemicals called ammino acids
What happens when protease breaks down the proteins
-the proteins are broken down into there induvidual acids where they are absobed into the blood stream
What happens to the structure of the proteins when they are absored into the bloodstream.
They are re structured to make human proteins - these are used for growth and repair
What is the structure of starch?
-chains of glucose molecules
What is the enzyme that breaks down carbohydrates?
what enzyme breakes down starch specifically
What happens when carbohydrates are digested
-simple sugars are produced
Where is amylase found
What is the structure of a lipid
one molecule of glycerol and three molecules of fatty acids
What are lipid molecules digested by?
What product is formed when lipids are broken down?
Where is lipase found?
Where is bile made and stored
-made in the liver
-stored in the gullbladder
What is the function of bile
-speed up the digestion of lipids