B3: Organisation And Digestion Flashcards
What is a tissue?
A group of cells of the same type
What is an organ?
A group of tissues that work together to peform a function
Put these in order of smallest to largest
Organ, tissue, organelle, organism, cell, organ system
Smallest - Organelle, cell, Tissue, Organ, Organ system, Organism - Largest
What are the names of some organ systems?
Circulatory system
Digestive system
Nervous system
Reproductive system
What is the function of the stomach in the digestive system ?
To churn the food and add hydrochloric acid and pepsin
What is the function of the large intestine in the digestive system?
It is where excess water is re-absorbed into the body
What are the 7 nutrient groups?
Carbohydrates, Proteins, Lipids, Minerals, Vitamins, Fibre, Water
What are enzymes used as?
Biological Catalysts
Are enzymes used up in reactions?
They speed up the reaction but are not used up
What is related to the way enzymes work?
A lock and a key
Why are enzymes related to lock and keys?
Because the enzyme and the substrate fit perfectly together like a lock and a key
What are the 2 types of digestion?
Mechanical and Chemical
What is mechanical digestion carried out by?
The teeth
What is chemical digestion carried out by?
Enzymes
What are the 2 parts needed to fit together for an enzyme to work?
Enzyme and substrate
To test for protein, what do you add to the solution?
Biuret
What colour will a solution turn after adding buiret if protein IS present?
Purple
How do you prepare a food to test for a food group (e.g protein)?
- Crush the food using a pestile and mortar.
- Add afew drops of DISTILLED water.
- Filter the contents of the mortar through a funnel with filter paper into a boiling tube.
What is the “optimum temperature” for an enzyme?
The temperature at which an enzymes activity is highest and it will work at the quickest rate
This is usually around 40°C
What happens to an enzyme when you go too far past the optimum temperature?
The enzyme denatures and can no longer function
What is the function of the mouth in the digestive system?
The teeth rip and chew the food into small pieces whilst the salivary gland adds saliva
What is the function of the oesophagus in the digestive system?
To transport the food from the mouth to the stomach
What is the function of the liver in the digestive system?
The liver produces bile which neutralises stomach acid and emulsifys (breaks up) fats
What is the function of the pancreas in the digestive system?
The pancreas produces protease, lipase and amylase - these are all enzymes that help digest the food in the small intestine
What is the function of the rectum in the digestive system?
It is where faeces are stored before they are passed out the anus
What is the function of the small intestine in the digestive system?
Finishes breaking down the food (using lipase, protease and amylase) so it can be absorbed out of the digestive system and into the blood
