Edexcel GCE Biology Unit 5 6BI05 June 2013

Original post by Dhaden

Mhmm, the Auxin one was weird the light was directly above. Still said that the artificial IAA would be grow higher.

Myosin thick filament, actin thin?

Eugnol I just talked about less voltage gated calcium ion channels being opened, less calcium ions + neurotransmitter released. Less frequent depolarisation and action potentials so therefore less pain? Don't think I've ever used the word less so many times in my life in a paragraph.

I said something along those lines for the eugenol drug question.

Reply 1282

Original post by AWAIS194

What is the difference between Starch and cellulose? I wrote that cellulose has alpha-glucose and beta-glucose whereas starch has alpha-glucose only, which I know is wrong :frown:

Cellulose is unbranched whereas starch is branched
Cellulose is made up of beta glucose units whereas starch is made up of alpha glucose units.

Reply 1283

Original post by Examboss177

Hi guys! Hope you all felt the exam went okayish!
What did people write for the question about NAD? (Where you had to identify NAD on the ETC as molecule W?) It said how is it formed....protein? transcription translation?

I said NAD is formed because NAD(H) lost the Hydrogen atom, as the electron was accepted by the Electron carrier molecule. etc.

Reply 1284

mar junior

Original post by Sly1

I said something along those lines for the eugenol drug question.

I Wrote that but i replaced the word with "none", i dont think ill get the marks because i implied that the drug is 100 percent effective so absolutely no calcium ions would enter the membrane when in reality only a reduced amount will

Reply 1285

Original post by AWAIS194

I said NAD is formed because NAD(H) lost the Hydrogen atom, as the electron was accepted by the Electron carrier molecule. etc.

I said the reduced NAD loses of shuttles its hydrogen atom onto the electron transport chain. The hydrogen atoms split into electrons and hydrogen ions. The electrons go through the series of electron carriers losing energy to pump the hydrogens ions from the mitochondiral matrix to the intermembrane space.....

(edited 10 years ago)

Reply 1286

Original post by mar junior

I Wrote that but i replaced the word with "none", i dont think ill get the marks because i implied that the drug is 100 percent effective so absolutely no calcium ions would enter the membrane when in reality only a reduced amount will

If the question said it REDUCES THE PAIN, then yes less calcium ions enter less neutrotransmitter bla blab ba

Reply 1287

mar junior

What did everyone write for the adaptations of mole rats?

I talked about lacking pain receptors so can tolerate high co2 levels
and polikothermy so no fur on the skin

Reply 1288

Original post by mar junior

What did everyone write for the adaptations of mole rats?

I talked about lacking pain receptors so can tolerate high co2 levels
and polikothermy so no fur on the skin

I said they are adapted to oxygen deprivation because they regain some of the immature characteristics at adult age. Lack of fur because of hot conditions and also went on to talk about other adaptions..

Reply 1289

Was one of the multiple choice questions Bipolar neurone?
And a Lower concentration of Na+ in the cell?

Can't believe I messed up the first question. Even crossed retinal but changed it to retinol :frown:

Reply 1290

Original post by AWAIS194

Was one of the multiple choice questions Bipolar neurone?
And a Lower concentration of Na+ in the cell?

Can't believe I messed up the first question. Even crossed retinal but changed it to retinol :frown:

I put bipolar neurone
the na+ one I just didn't have a clue. I put increased. lol
And yes it was retinal.

Reply 1291

The questions I really liked was the article questions lol

Reply 1292

Nilie

Original post by AWAIS194

Was one of the multiple choice questions Bipolar neurone?
And a Lower concentration of Na+ in the cell?

Can't believe I messed up the first question. Even crossed retinal but changed it to retinol :frown:

was retinal A or D?
i think i screwed that up as well =/
damn

Reply 1293

Original post by Nilie

was retinal A or D?
i think i screwed that up as well =/
damn

retinal was A! :frown:

Reply 1294

Original post by Sly1

The questions I really liked was the article questions lol

Yep, good questions - roughly 8 marks on Unit 5 with the thermoregulation question and there was one more on unit 5 which I can't remember.

Anyone know if acrosome will be a suitable reason for it to not be motile? Or would lack of flagella and mitochondria be the only answers?

Reply 1295

Nilie

Original post by AWAIS194

retinal was A! :frown:

ah nevermind.... i already know 14 marks i've lost... and thats just what i know... that a in not happenin =( thats bad

Reply 1296

BOOM!

What did everyone write for the sperm being imotile?

Reply 1297

Lgambo

For the IAA question, I put the shoot would bend to the right.
I said this is because the more active auxins stimulate growth and cell elongation, so the cells on the left side would be affected more and grow faster thus it bends to the right.
Not sure how right that is though.

The enzyme question really threw me, it didn't even cross my mind to write about active sites bla bla. I wrote that the process was anaerobic respiration, and wrong things like "enzyme 3 helps convert pyruvate to lactate bla bla"

Reply 1298

Nilie

Original post by BOOM!

What did everyone write for the sperm being imotile?

under developed/absent tail

few/no mitochondria

Reply 1299