Psyxwar's Biology 3/4 Question Thread

[pi]

Could I have a source on this please?

First line: http://www.biog1105-1106.org/demos/105/unit1/fibrous_v_glob.html

[psyxwar]

First line: http://www.biog1105-1106.org/demos/105/unit1/fibrous_v_glob.html

I saw that too, but the article goes on to say that "fibrous proteins generally have only primary and secondary structure whereas globular proteins have tertiary and sometimes quaternary structure in addition to primary and secondary structure." Don't all proteins by definitions have tertiary structure? (though I guess if tertiary structure is due to side-chain interaction, a fibrous protein may not have tertiary structure... but then aren't there proteins like collagen which have quaternary structure? Would these have tertiary structure as well?)

[pi]

I don't think having a tertiary structure is part of the definition of a protein?

[Yacoubb]

I saw that too, but the article goes on to say that "fibrous proteins generally have only primary and secondary structure whereas globular proteins have tertiary and sometimes quaternary structure in addition to primary and secondary structure." Don't all proteins by definitions have tertiary structure? (though I guess if tertiary structure is due to side-chain interaction, a fibrous protein may not have tertiary structure... but then aren't there proteins like collagen which have quaternary structure? Would these have tertiary structure as well?)

Do you think perhaps that globular proteins, involved in more functional roles such as enzymes catalysing reactions or haemoglobin carrying oxygen, that tertiary structures are vital for their function, in creating an active site that ultimately contributes to their function, wheras fibrous proteins, which are more structural orientated, require no intricate tertiary structure, to bind to any substrate (in case of enzymes) or carry any particular molecule (in case of haemoglobin)?

[pi]

^I'd lean to agree with that logic

[psyxwar]

I don't think having a tertiary structure is part of the definition of a protein?

Hmm, maybe not. It's just what I've been taught so far at the 3/4 level.

http://en.wikipedia.org/wiki/Intrinsically_unstructured_proteins <- after a bit of research proteins like this exist too

[psyxwar]

Do you think perhaps that globular proteins, involved in more functional roles such as enzymes catalysing reactions or haemoglobin carrying oxygen, that tertiary structures are vital for their function, in creating an active site that ultimately contributes to their function, wheras fibrous proteins, which are more structural orientated, require no intricate tertiary structure, to bind to any substrate (in case of enzymes) or carry any particular molecule (in case of haemoglobin)?

Yeah I'd agree with that, I was more confused as to whether or not fibrous proteins actually have what could be classified as tertiary structure.

[pi]

Hmm, maybe not. It's just what I've been taught so far at the 3/4 level.

http://en.wikipedia.org/wiki/Intrinsically_unstructured_proteins <- after a bit of research proteins like this exist too

You have to remember that VCE bio is relativity simplistic ^.^

[psyxwar]

What would you call the third step of respiration? Since oxidative phosphorylation comprises both the electron transport chain and chemiosmosis, wouldn't it be incorrect to label the third phase just the electron transport chain (as the ATP is produced during chemiosmosis, not the electron transport chain)?

[Stick]

You've gone into far too much detail. If you're still keen on finding the answer however, that's fine, since Biology is a very interesting subject and even I have read up on extra stuff simply because it's so fascinating.

[psyxwar]

You've gone into far too much detail. If you're still keen on finding the answer however, that's fine, since Biology is a very interesting subject and even I have read up on extra stuff simply because it's so fascinating.

Haha yeah you just keep reading and reading...

I'm more wondering if it'd sufficient/ correct to just use the term "electron transport chain" in 3/4 biology though as opposed to say the actual labelling (since that's readily googlable, but the former isn't so much)

Edit: answered, thanks guys.

[pi]

What would you call the third step of respiration? Since oxidative phosphorylation comprises both the electron transport chain and chemiosmosis, wouldn't it be incorrect to label the third phase just the electron transport chain (as the ATP is produced during chemiosmosis, not the electron transport chain)?

"Electron transport chain" is more than enough mate.

We're doing only doing VCE bio

Although, personally, it's good to see you reading above and beyond, that's what bio should be about

[Yacoubb]

What would you call the third step of respiration? Since oxidative phosphorylation comprises both the electron transport chain and chemiosmosis, wouldn't it be incorrect to label the third phase just the electron transport chain (as the ATP is produced during chemiosmosis, not the electron transport chain)?

Is the oxidative phosphorylation the formation of the ATP molecules, by adding another inorganic phosphate molecule to the Adenose Di-phosphate (ADP)? And I think the Electron Transport Chain is adequate for 3/4 Biology

[psyxwar]

Is the oxidative phosphorylation the formation of the ATP molecules, by adding another inorganic phosphate molecule to the Adenose Di-phosphate (ADP)? And I think the Electron Transport Chain is adequate for 3/4 Biology

Oxidative phosphorylation includes the electron transport chain (which is where the energy necessary to synthesise ATP from ADP and Pi comes from) and chemiosmosis, which is when the ATP is actually synthesised (via ATP Synthase). That's simplified a lot and if you're interested you can read up on it online.

[psyxwar]

If an experimental design question asks us to "explain what results would support or negate the student's hypothesis", are we able to just describe what results would support the hypothesis (since results outside these would negate the hypothesis, assuming the experimental design was valid/ all extraneous variables were controlled)? This is how checkpoints answered the question anyway.