VCE Biology Question Thread

[scarletmoon]

I got my first sac back and the mark that I got was unexpected. The sac was said to contribute 40% of the study sac what does that mean? My second sac is worth 30%.

You just need have a high rank in your cohort to get a good study score

[caitlynharbrow]

Welcome all you budding biologists! On this board there are a lot of individual-question threads throughout the year. I've made this thread both to help get your VCE biology questions answered as quickly as possible, as well as to reduce clutter on this board where possible.

Happy studying!

Hello, what would be some questions asked about enzymes and hydrogen peroxide?

[scarletmoon]

Hello, what would be some questions asked about enzymes and hydrogen peroxide?

Know all the theory behind enzymes and its behaviour in different conditions. Why is hydrogen peroxide broken down? What happens if it isn't broken down? Would the reaction speed up if you add more enzmes? What would happen to the rate of reaction if you add more H2O2(substrate)? Affect of temperature on enzyme activity? Also be familiar with different types of enzyme graphs (these should be in your textbook)

[kimmytaaa]

Hello, what would be some questions asked about enzymes and hydrogen peroxide?

you might need to know how to draw both the temperature and pH, also maybe read over Non-competitive inhibition and competitive and know the difference between them and how they function in enzymes.

[Jay.C]

Hey guys!
I did an experiment the other day and we had catalase in multiple test tube. We then proceeded to change the temperatures of each test tube. One was 0 degree, 20 degrease, 40 degrease, 60 degrease, 80 degrease and 100 degrease. After this we inserted hydrogen peroxide into each test tube and observed how much oxygen was produced.

I have some questions about this experiment:
1. Was the control the beaker that was heated to the enzymes optimum temperature?
2. Is denaturing is caused by the breaking of hydrogen bonds in terms of heat.
3. What are some limitations of this experiment? 
4. Was anything besides heat effecting enzyme function?
5. Was the bubbles caused by oxygen being produced?

Thanks guys 

[scarletmoon]

Hey guys!
I did an experiment the other day and we had catalase in multiple test tube. We then proceeded to change the temperatures of each test tube. One was 0 degree, 20 degrease, 40 degrease, 60 degrease, 80 degrease and 100 degrease. After this we inserted hydrogen peroxide into each test tube and observed how much oxygen was produced.

I have some questions about this experiment:
1. Was the control the beaker that was heated to the enzymes optimum temperature?
2. Is denaturing is caused by the breaking of hydrogen bonds in terms of heat.
3. What are some limitations of this experiment? 
4. Was anything besides heat effecting enzyme function?
5. Was the bubbles caused by oxygen being produced?

Thanks guys 

1. Yes so the one at 40 degrees would be the control
2. Yes because hydrogen bonds help maintain the integrity of the tertiary structure of the enzyme (not entirely sure of this could be wrong)
4. pH, enzyme concentration, substrate concentration. For this experiment it should only be heat that's affecting function since the aforementioned variables should be controlled
5. Yes because it's one of the products of the reaction

Not sure about 3. Sorry

[StupidProdigy]

Hey everyone!
I'm a bit stuck on this question "Explain how the structure of the plasma membrane affects the movement of different substances through it"
Basically I'm not to sure whether to talk about the (or even mention) the fluid mosaic model, or whether to talk about the selective permeability and substances etc. Thanks

[Jay.C]

Hey guys quick question. If I got a 14/15 in my first sac is that considered an A+?

[scarletmoon]

Hey guys quick question. If I got a 14/15 in my first sac is that considered an A+?

Of course!

[bae]

Hey everyone!
I'm a bit stuck on this question "Explain how the structure of the plasma membrane affects the movement of different substances through it"
Basically I'm not to sure whether to talk about the (or even mention) the fluid mosaic model, or whether to talk about the selective permeability and substances etc. Thanks

Well,

The fluid mosaic model describes a phospholipid bilayer with embedded proteins. Such a structure contains phospholipids with hydrophilic heads and hydrophobic tails, allowing lipid soluble substances to pass through the membrane with ease. However, larger molecules need to enter the cell via other methods, and this is where the role of proteins is vital, with features such as protein channels and carrier proteins becoming essential in ensuring passage for certain substances across the membrane. As you can see, this selective permeability can be owed to the fluid mosaic model of the membrane, tying your two points together.

I hope that's what you were asking 

[cosine]

What is the equivalence of plasmolysis to an animal cell, is it just called flaccid? Thanks

[grannysmith]

What is the equivalence of plasmolysis to an animal cell, is it just called flaccid? Thanks

I'd just say it's 'shrivelled'.

[cosine]

I'd just say it's 'shrivelled'.

What's the biological term though?

[Spxtcs]

What's the biological term though?

'crenation'. I.e. the cell is crenated.

[cosine]

'crenation'. I.e. the cell is crenated.

Woops, i was meant to say the opposite. What would be the word when a cell doesnt quite lyse yet, is there a term to describe it? I know its turgid for a plant cell, but animals?