Biology cwk on Enzymes

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Fluffy

Catalase is one of many enzymes that can break down H2O2. Another important thing (if talking catalase) is that if the fenton reaction does not go to completion, you can gererate free radicals galore. Not good if you're DNA; a cell wall; a protien etc.

Poor cell wall :frown:

Reply 21

Fluffy

Of course, the doc of genetics and cancer knows all.

Reply 22

gzftan

Fluffy

Chemistry??? Or way-advanced bio-chemistry?!??!!?!? AAAAAARRRGGGHHH!!!! My head hurts!!! :frown:

Reply 23

Fluffy

Hell! not stand alone chemistry. Chemistry makes me break out in a rash! Shudder!

But on a serious note, if you want to get good A-level marks, you need to be reading to the level of year 1 degree. Not that much more dificult, but if you can demonstrate wide knowledge outside ofhte scope of your syllabus, you'll be laughing!

Reply 24

RetiredAccount89

coolguy

does any1 know any detailed science why the rate of reaction of enzyme activity increases as concentration of hydrogen peroxide increases. please I need some very detailed scientific knowledge.

ok, a quick scan reveals that the people here suck at biology.
this is GCSE stuff!

The Hydrogen Peroxide is your substrate. That is to say it's the molecule that the enzyme is acting upon. The enzyme will break it down to water and oxygen. That's why you often meaure it by O2 collected, or number of bubbles per min etc

Think of it like this. The enzyme can do a maximum speed of breakdowns per minute. It's a maximum speed because that is the time it takes to
get the h202 into the enzyme, the reaction to take place, it to leave, and another to replace it.

Now look at that list again
1) H202 bind to active site of the enzyme
2) breakdown reaction to occur
3) breakdown products released (water and oxygen)
4) Another h202 binds to active site

If you keep temperature and ph constant (and dont do anything like add salts etc) then steps1,2 and 3 will be constant rate. They won't change.
Step 4 of course relies on how much h202 there is about in the solution.
Molecules don't line up ready to be broken down.

Analogy
It's more like a school playground when you play 'kiss chase' everyone is running around randomly, and sometimes someone bumps into the kisser (the enzyme).
The more people there are, the more likely someone will be kissed (broken down)
The maximum reaction rate (at given temp and ph) is the point where the kisser is kissing as fast as he/she can. Having more people (substrates) won't mean a fast rate.

Hope that helps
J

Reply 25

RetiredAccount89

Fluffy

you've lead a bloody weird career.
why are you only now starting a med degree?
J

Reply 26

Fluffy

foolfarian

you've lead a bloody weird career.
why are you only now starting a med degree?
J

In a nut shell:

I was critically ill for most of my Lower 6th year (spent 9 months in hospital), was too pig headed to repeat the year and took my A-levels anyway. Weren't bad, but given I hadn't covered half the course, weren't fab either (A,C,D)

Hadn't even thought about careers back then. Liked genetics, so applied to do that with a view to becoming a NHS cytogeneticist. When I got my degree and looked into Cyto properly I was disgusted to find that the starting salary was a meer £6.5K pa (and you had to have a 2i or above!).

As I enjoy research I did a D.Phil instead, which was cancer and DNA damage based. While doing my D.Phil, I started volunteering on the ward of my local hospice to see the end point and goals of cancer based research and to try to make myself mega focused. Instead I fell in love with medicine. So decided to take the plung and I start in Sept.