B3 Organisation & Digestive System 📚👄 Flashcards
What is another name for organelles?
Subcellular structures
What are organelles?
Things in cells like nucleus or mitochondria etc.
What are tissues?
A set of similar cells working together to carry out a particular function
What are organs?
A set of dif. tissues working together to perform a particular function
What is a catalyst?
Increases the speed of a reaction without being changed or used up in the process
Another name for Enzyme?
Biological catalysts
What is an enzyme?
biological catalysts which speed up the rate of reactions in a body
What is the Lock and Key Theory?
Original theory where scientists thought the active site had to fit the substrate molecule PERFECTLY
What is the Induced Fit model?
Where the active site of the enzyme is complementary to the substrate (actually changed shape slightly as it binds to the substrate)
What is the Benedicts test used to test?
Sugars
What is the Biuret test used to test?
Proteins
What is Iodine used to test for?
Starch
What are the 3 main groups of Nutrients?
- Carbohydrates
- Proteins
- Fats
What foods are Carbohydrates found in?
Pasta, potatoes, rice
What is the main Carbohydrate?
Starch
What is starch broken down by?
Amylase
Where is amylase made in the body?
- Salivary Glands (in the mouth)
- Pancreas
- Small Intestine
What foods are proteins found in?
Chicken, Eggs, Nuts
What are proteins broken down by in the body?
Protease
What are proteins broken down into?
Broken down by proteases into amino acids
Where is protease made in the body?
- Stomach (pepsin)
- Pancreas
- Small Intestine
What are some examples of food where fats (lipids) are found?
- Butter
- Cheese
- Oil
What are lipids broken down into?
Glycerol & Fatty acids
Where is lipase enzyme produced in the body?
Small Intestine & Pancreas
Describe the first part of the digestion process?
- Food enters the mouth where food is broken down mechanically by chewing
- the salivary glands produce amylase enzymes which breaks down carbohydrates
-then the food passes down through the oesophagus into the stomach
What is the process after food has passed through the oesophagus and into the stomach?
Stomach
- Contracts muscular walls to push and mix food around
- produces PEPSIN (protease enzyme which breaks down proteins)
- also produces hydrochloric acid to kill germs and provide a right environment for pepsin to function
What happens after the stomach in the digestive system?
- Food is then squeezed into the small intestine
- In the small intestine food is absorbed into the blood stream
- also produces digestive enzymes to assist the digestion process further
What does the pancreas do?
Produces lots of digestive enzymes which is pushed through to the small intestine in the form of ‘pancreatic juices’
Where is bile stored?
Gall bladder
What does the gall bladder do?
Stores and releases BILE
What is the function of bile and where is it produced?
- produced in the liver
- neutralises stomach acid
and emulsifies fats making them small giving them a larger surface area to be broken down easier and faster
What are the adaptations of the small intestine?
- Villi in the inner lining which increase surface area
- Villi only have a single layer of surface cells = shorter distance for nutrients to diffuse
- Villi also have very good blood supply - which maintains the concentration gradient
What is the FUNCTION of the LARGE INTESTINE?
- absorbs excess water
-leaving behind feces in the rectum
Where are feces stored?
Rectum
Order of the digestive system?
Mouth
Oesophagus
Stomach
Small intestine where pancreatic juices and bile are received
Large intestine
Rectum
What is the name for the pH where enzymes work best?
Optimal pH
What does Optimal pH mean?
pH where an enzyme works best
What does DENATURED mean?
When an enzyme changes shape due to chain in temperature and/or pH, that it can no longer fit the substrate molecule
