Section 2 - Cells And Control Flashcards
Why do enzymes break down molecules
Many molecules of the food are too big to be passed through the walls of the digestive system. This means the digestive enzymes have to break them down into more soluble and smaller molecules. These then can pass easily through the walls of the digestive system and to be absorbed into the bloodstream. They can pass into cells and be used by the body.
Function of enzymes
- they have special shapes so they can ๐พ๐๐ฉ๐๐ก๐ฎ๐จ๐ ๐ง๐๐๐๐ฉ๐๐ค๐ฃ๐จ.
- ๐ฝ๐ง๐๐๐ ๐จ ๐๐ค๐ฌ๐ฃ big molecules
- some enzymes can ๐ ๐ค๐๐ฃ ๐ข๐ค๐ก๐๐๐ช๐ก๐๐จ ๐ฉ๐ค๐๐๐ฉ๐๐๐ง.
How do enzymes help plants?
Plants store energy in the form of starch- carbohydrates. When the plant needs energy, the enzymes break down the starch into smaller molecules- sugars. This can then be respired to transfer energy to be used by the cells
______ converts carbohydrates into ________
- Carbohydrases
- Simple sugars
What converts proteins into amino acids?
Proteases
________ converts lipids into _________
- Lipases
- Glycerol and fatty acids
What happens when lipids are broken down
The fatty acids will lower the pH of the solution they are in
What are lipids
Fats and oils
Why are proteins, lipids and carbohydrates important to be broken down
They can be used for growth and other life processes
How can carbohydrates be synthesised
Joining simple sugars together
Glycogen synthase
An enzyme that joins together lots of chains of glucose molecules to make glycogen which is a molecule used to store energy in animals
How are proteins synthesised
Joining amino acids together and enzymes catalyse the reactions for this
Diffusion
The net movement of particles from a higher concentration to a lower concentration down the concentration gradient
Concentration gradient
If something moves from an area of a ๐๐๐๐ ๐๐ค๐ฃ๐๐๐ฃ๐ฉ๐ง๐๐ฉ๐๐ค๐ฃ to a ๐๐ค๐ฌ ๐๐ค๐ฃ๐๐๐ฃ๐ฉ๐ง๐๐ฉ๐๐ค๐ฃ, it is said that it moves ๐ฟ๐ค๐ฌ๐ฃ the ๐พ๐ค๐ฃ๐๐๐ฃ๐ฉ๐ง๐๐ฉ๐๐ค๐ฃ ๐๐ง๐๐๐๐๐ฃ๐ฉ if itโs from an area of ๐๐ค๐ฌ to ๐๐๐๐, it is moving ๐๐ฅ the ๐พ๐ค๐ฃ๐๐๐ฃ๐ฉ๐ง๐๐ฉ๐๐ค๐ฃ ๐๐ง๐๐๐๐๐ฃ๐ฉ
Where does diffusion occur๏ฟผ
It only happens in ๐ก๐๐ฆ๐ช๐๐๐จ and ๐๐๐จ๐๐จ. This is because the ๐ฅ๐๐ง๐ฉ๐๐๐ก๐๐จ in these substances are able to ๐ข๐ค๐ซ๐ ๐๐ง๐๐๐ก๐ฎ ๐๐ฃ๐ ๐ง๐๐ฃ๐๐ค๐ข๐ก๐ฎ
Osmosis
The net movement of water molecules from an area of ๐๐๐๐ ๐ฌ๐๐ฉ๐๐ง ๐๐ค๐ฃ๐๐๐ฃ๐ฉ๐ง๐๐ฉ๐๐ค๐ฃ to a ๐ก๐ค๐ฌ ๐ฌ๐๐ฉ๐๐ง ๐๐ค๐ฃ๐๐๐ฃ๐ฉ๐ง๐๐ฉ๐๐ค๐ฃ through a ๐จ๐๐ข๐ ๐ฅ๐๐ง๐ข๐๐๐๐ก๐ ๐ข๐๐ข๐๐ง๐๐ฃ๐. Going ๐๐ค๐ฌ๐ฃ the ๐๐ค๐ฃ๐๐๐ฃ๐ฉ๐ง๐๐ฉ๐๐ค๐ฃ ๐๐ง๐๐๐๐๐ฃ๐ฉ.
What is a semi permeable (also known as partially permeable) membrane?
A membrane with very ๐จ๐ข๐๐ก๐ก ๐๐ค๐ก๐๐จ in it. This is so only ๐ฉ๐๐ฃ๐ฎ ๐ข๐ค๐ก๐๐๐ช๐ก๐๐จ like water can go through it and bigger molecules canโt.
Which way does the water molecules travel through the membrane in osmosis
The water molecules usually travel both ways as the water molecules move about randomly all the time. However, because there are more water molecules on one side theres a steady net flow of water into the region with fewer water molecules
Active transport
The movement of particles across a membrane from a ๐ก๐ค๐ฌ๐๐ง ๐๐ค๐ฃ๐๐๐ฃ๐ฉ๐ง๐๐ฉ๐๐ค๐ฃ to a ๐๐๐๐ ๐๐ค๐ฃ๐๐๐ฃ๐ฉ๐ง๐๐ฉ๐๐ค๐ฃ ๐ช๐จ๐๐ฃ๐ ๐๐ฃ๐๐ง๐๐ฎ. This means it is a ๐ฅ๐๐จ๐จ๐๐ซ๐ process as it uses energy ๐ฉ๐ง๐๐ฃ๐จ๐๐๐ง๐ง๐๐ ๐๐ช๐ง๐๐ฃ๐ ๐ง๐๐จ๐ฅ๐๐ง๐๐ฉ๐๐ค๐ฃ.
How is active transport used in the digestive system
When thereโs a high concentration of nutrients in the gut than the blood. The nutrients diffuse naturally into the blood. However, sometimes there is a lower concentration of nutrients in the gut than in the blood. Active transport allows nutrients to be taken into the blood even though the concentration gradient is the wrong way. This helps us stop starving
What is the aim of investigating osmosis
You have to put ๐ฅ๐ค๐ฉ๐๐ฉ๐ค ๐๐ฎ๐ก๐๐ฃ๐๐๐ง๐จ into different concentrations of ๐จ๐ช๐๐ง๐ค๐จ๐ ๐จ๐ค๐ก๐ช๐ฉ๐๐ค๐ฃ๐จ in order to see what ๐๐๐๐๐๐ฉ different ๐ฌ๐๐ฉ๐๐ง ๐๐ค๐ฃ๐๐๐ฃ๐ฉ๐ง๐๐ฉ๐๐ค๐ฃ๐จ have on them
Steps of the osmosis practical
- Prepare sucrose solutions of different concentrations from pure water to very concentrated
- Cut a potato into 1c, in diameter from the same potato
- Divide the cylinders into groups of 3 and use a mass balance to measure the mass of each group
- Place one group in each solution and leave for at least 40 mins
- Remove the cylinders and pat dry so it moves excess water from the surface and you will get an accurate measurement
- Weigh each group again and record the result.
- The sucrose solution is the only thing you will change in the experiment. The size of the potato must be kept the same or the results will be invalid
How do you find the result of the osmosis investigation
Calculate the Percentage change in mass for each cylinder before and after.
New - original/ original x 100
You then plot a graph and analyse your result.
When the curve crosses the x-axis, that means the fluid inside the cylinders and the sucrose solution have the same water solution (isotonic)
the points below the x-axis, the water concentrating of the sucrose is lower than Iโm the cylinders. This causes the sun lingers to lose water so the mass decreases
The _______ the concentration of the sucrose solution, the __________ the ________________
- Higher
- Lower
- Water concentration