Organisation Flashcards Preview

GCSE Biology Paper 1 > Organisation > Flashcards

Flashcards in Organisation Deck (96)
Loading flashcards...

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?

-lipids (fats)
-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

-new carbohydrates
-new lipids
-new proteins
-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

-pancreatic fluid


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?

-fatty acids


Where is lipase found?

-pancreatic fluid
-small intestine


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
-neutrilise acids


how does bile speed up the digestion of lipids

-it converts small droplets of lipids into larger droplets
-it is said that it emulsifies
-it largly increases the surface area and increases the rate of lipid breakdown by lipase