Chapter 2 - Organisation Flashcards
What is a tissue?
The tissue is a group of similar cells that work together to carry out a particular function
What is an organ?
And organ is a group of different tissues that work together to perform a certain function
What is an organ system?
A group of organs working together
What are examples of organ systems?
The digestive system
it is made up of glands e.g. the pancreas and salivary glands
the stomach and small intestine which digests food
the liver which produces bile
the small intestine which absorbs soluble food molecules
the large intestine which absorbs water from undigested food leaving faeces
What is a catalyst
A catalyst is a substance which increases the speed of a reaction without being changed or used up in the reaction
What are enzymes
Enzymes are all large proteins and all proteins are made up of chains of amino acid’s
They act as biological catalysts
What do enzymes do
They reduce the need for high temperature and we only have enzymes to speed up useful chemical reactions in the body
Do you chemical reactions usually involve?
They usually involve things being either split apart or joined together
what does every enzyme have
Every enzyme has an active site with a unique shape that fits onto substance involved in a reaction
What is the name of the model that shows an enzyme in action
The lock and key model
What can change the rate of an enzyme catalysed reaction
The temperature and pH
However if it gets too hot some of the bonds holding the enzyme together break this changes the shape of the enzymes active site so the substrate won’t fit anymore the enzyme is said to be denatured
If the pH is too high or too low it interferes with the bonds holding the enzyme together this changes the shape of the active site and denatures the enzyme
On average what is the optimum pH that enzymes work best at
Neutral pH 7
How do you calculate the rate of reaction
Rate=1000/time
What do you digestive enzymes do
They break down big molecules such as starch, proteins and fats. These are too big to pass through the walls of the digestive system so digestive enzymes break these big molecules down to smaller ones such as sugars, amino acids, glycerol and fatty acid’s so they can pass easily through the walls of the digestive system allowing them to be absorbed into the bloodstream
What enzyme converts carbohydrate and what do they convert it into
Carbohydrates this convert carbohydrates into simple sugars
What is an example of carbohydrase
Amylase
What does amylase do?
It breaks down starch
Where is Amylase made
salivary glands
pancreas
small intestine
What does amylase break down starch into?
Maltose
What enzyme convert proteins and what into?
Proteases convert proteins into amino acid’s
Where is protease made?
Protease is made in:
the stomach
the pancreas
the small intestine
What enzyme converts lipids and what into
Lipases convert lipids into glycerol and fatty acid’s
Where are lipases made?
The pancreas and
small intestine
What does the body use the products of digestions to do
They can be used to make new carbohydrates proteins and lipids and some of the glucose that’s made is used in respiration
Where is bile produced?
Where is it stored?
Where does it go once it is released?
File is produced in the liver it stored in the gall bladder before it’s released into the small intestine
What does bile do
The hydrochloric acid in the stomach makes the pH to acidic for enzymes in the small intestines to work properly. Bile is an Alkaline - it neutralises the acid and makes conditions alkaline
It’s emulsifies fats which means it breaks the fat into tiny droplets. This gives a much bigger surface area of fat for the enzyme lipase to work on which makes digestion faster
Where are the enzymes used in digestion produced?
Enzymes used in the digestive system are produced by specialised cells in glands and in the gut lining
What do the salivary glands produce
These produce amylase in the saliva
What does the stomach do during digestion?
It pummels the food with its muscular walls
it produces the protease enzyme
it produces hydrochloric acid for two reasons:
-to kill bacteria to give the right pH
-for the protease enzyme to work which is pH 2 (acidic)
What does the liver do during digestion
This is where bile is produced
Bile neutralises stomach acids and emulsifies fats
What does emulsifies mean
To make something into smaller droplets
What does the gall bladder do during digestion?
This is where bile is stored before it’s released into the small intestine