Cell Organisation Flashcards
What are cells?
The basic building blocks that make up all organisms.
What do cells form?
Cells form tissues, which forms organs, which forms organ systems.
What are tissues?
A group of similar cells that work together to carry out a particular function.
What’s an organ?
A group of different tissues that work together to perform a certain function.
What are enzymes and what do they do?
Enzymes are proteins that act as biological catalysts and they speed up reactions.
What does the muscular, glandular and epithelial tissue do?
Muscular: contracts to move whatever is attached to
Glandular: makes and secretes chemicals e.g enzymes
Epithelial: covers parts of the body e.g the inside of the gut
How do enzymes work?
The substrate must fit into the enzyme’s active site.
Enzymes can only catalyse one specific reaction.
What’s the induced fit model of enzyme action?
The active site changing shape a bit to bind it and the substrate tighter.
What factors affect enzymes?
Temperature and pH
How do you investigate the effect of pH on enzyme activity?
- Put a drop of iodine solution into wells of a spotting tile.
- Set up the bunsen burner, heatproof mat, tripod and gauze.
- Place a beaker with water on the tripod and heat it till 35 degrees.
- Add each 1cm3 of amylase solution and a buffer solution of pH 5 to a boiling tube and then put the boiling tube into the beaker for 5 minutes.
- Add 5cm3 of a starch solution to the boiling tube and mix everything in the boiling tube and start a stopwatch.
- Take a sample from the boiling tube every 30 seconds and put it into a well of the spotting tile. If the iodine solution is brown/orange, starch isn’t present; if the iodine solution is blue/black, starch is present.
- Repeat the experiment with buffer solutions with different pH values.
What the equation for rate of reaction?
amount of product or reactant / time
What’s amylase and where’s it found?
It’s an carbohydrase that breaks down starch (carbohydrates) into simple sugars.
It’s found in the salivary glands, the pancreas and the small intestine.
What does protease do and where’s it found?
It breaks down proteins into amino acids and it’s found in the stomach, the pancreas and the small intestine.
What do lipase do and where’s it found?
It converts lipids into glycerol and fatty acids and it’s found in the pancreas and the small intestine.
What does bile do and where is it produced and stored?
Bile neutralises hydrochloric acid in the small intestine, makes conditions alkaline and breaks fats down into droplets.
Produced in the liver and stored in the gall bladder
Where are enzymes produced in the digestive system?
Glands and the gut lining
What does hydrochloric acid do?
Kill bacteria
Give the right pH for the protease enzyme to work
How do you use the Benedict’s test for sugars?
- Put 5cm3 of the food sample on a test tube
- Add a few drops of Benedict’s solution to the test tube.
- Put the test tube in an already prepared water bath set at 75 degrees for 5 minutes.
- If the sample contains a reducing sugar the solution will turn from blue to green, yellow or brick red.
How do you use iodine solution to test for starch?
- Put 5cm3 of the food sample to a test tube.
- Add a few drops of iodine solution to the test tube and shake it gently.
- If the sample contains starch, the colour will change from browny orange to black or blue black
How do you use the biuret test to test for proteins?
- Put 2cm3 of the food sample in a test tube.
- Add 2cm3 of biuret solution to the test tube and gently shake it.
- If the food sample has proteins, the colour will change from blue to purple.
How do you use the Sudan III test to test for lipids?
- Put 5cm3 of the food sample to a test tube.
- Add 3 drops of Sudan III stain solution to the test tube and gently shake it.
- If lipids is present, the mixture will separate into two layers, with the top layer being bright red.