B2 Flashcards
(76 cards)
What are cells?
Cells are the basic building blocks of all living organisms.
What are tissues?
A tissue is a group of cells with a similar structure and function.
What are organs?
Organs are aggregations of tissues performing specific functions.
What are organ systems?
Organs are organised into organ systems, which work together to form organisms.
What are 2 examples of tissues?
- Muscular tissue - contracts to move whatever it’s attached to. 2. Glandular tissue - secretes chemicals like enzymes and hormones.
What is an example of an organ?
The stomach which is made of muscular tissue etc.
What is an example of an organ system?
The digestive system
What is a catalyst?
A catalyst speeds up the rate of the reaction by giving the energy another path to travel to. It does not use up any reactants.
What is the aim of the digestive system?
To digest and absorb food
How does the lock and key method work for enzymes?
There is a specific substrate which fits the specific active site.
What happens to an enzyme when you increase the temperature too much?
Some of the bonds holding the enzyme together break so the active site changes so the substrate doesn’t fit. It is denatured.
What happens to an enzyme when you change the pH too much?
Some of the bonds holding the enzyme together break so the active site changes so the substrate doesn’t fit. It is denatured.
Where is amylase produced? (3)
- Small intestine. 2. Pancreas. 3. Salivary glands
Where is lipase produced? (2)
- Small intestine. 2. Pancreas
Where is protease produced? (3)
- Small intestine. 2. Pancreas. 3. Stomach
What does amylase break down and into what?
Breaks down starch into maltose and other sugars.
What does carbohydrase break down and into what?
Breaks down carbohydrates into simple sugars
What does lipase break down and into what?
Breaks down lipid (fats and oils) into fatty acids and glycerol
What does protease break down and into what?
Breaks down proteins into amino acids.
Where is bile made and stored?
Made in the liver and stored in the gallbladder.
What does bile do?
It is alkaline to neutralise hydrochloric acid from the stomach. It also emulsifies fat to form small droplets which increases the surface area.
How can bile increase fat breakdown?
The alkaline conditions and large surface area increase the rate of fat breakdown by lipase.
Required practical activity 5: investigate the effect of pH on the rate of reaction of amylase enzyme. (6)
- Put a drop of iodine solution into every spotting tile. 2. Heat water until 35 degrees over bunsen burner. 3.Use a syringe to add 1cm cubed of amylase solution and buffer solution with pH 5 and wait 5 mins. 4. Use a different syringe to add 5cm cubed of starch to beaker and mix and start clock. 5. Every 30 seconds add this to spotted tile. 6. When it stays orangey brown starch is no longer present.
What’s the test for sugars and how does it work? (4)
Benedict’s test. 1. Transfer 5cm cubed of food sample into a test tube. 2. Set water bath to 75 degrees. 3. Add Benedict’s solution using a pipette and add to water bath and leave for 5 mins. 4. If protein is present, it should change from blue to green or yellow or red (depending on how much sugar).