Edexcel Biology Unit 1 Revision Questions

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really ? well it wouldnt hurt to know about it. but i mean every dna replication that has come up in the past i've written what i know (above) and have gotten full marks for it. myabe its just an extra thing.....

Yea I guess...

hmm well ive finished going over unit 1 time for a couple of thread on revision for units 2-5 lol.

Reply 23

rahmed

The diagram below shows apparatus that can be used to measure the rate of anaerobic respiration in yeast cells. The tube contains a yeast suspension in 1% glucose solution and a redox indicator. The pyrogallol solution absorbs oxygen.

(a) (i) Name one suitable redox indicator which could be used in this experiment.
..........................................................................................................................
(1)
(ii) Give one change you would expect to observe during the experiment as the yeast respires and give a reason for your answer.
Change..............................................................................................................
Reason..............................................................................................................
..........................................................................................................................
(2)
(b) Describe how you could use the apparatus to investigate the effect of temperature on anaerobic respiration of glucose by yeast.
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
(3)
(Total 6 marks)

Diagram is attached, one sec...

sadasd.jpg69.8KB

Reply 24

iceman_jondoe

suitable redox indicator would be TTC- i dont think you would have to write out its name in full would you ? or wouldnt you ?

When TTC is reduced it forms a red compound called formazans which is insoluble i think. this is because as the yeast is respiring anaerobically glycolysis is taking place at least and hydrogen is being released because of dehydrogenase enzymes

..with the last q i cant think of anything aint revised unit 4 yet...but im pretty sure theres a waterbath involved in there somewhere....

Reply 25

rahmed

I went to a lot of trouble to get this question for you (attached), so someone better do it!

took_me_ages.jpg350.9KB

Reply 26

rahmed

come on noobs, answer this!

Reply 27

iceman_jondoe

just typind it up in microsoft word :biggrin:

rahmed

See attached took me a long time rahmed i hope your prepared to mark it !. dunno if is right though

Bio q.doc29.7KB

Reply 30

asadtamimi

Those 2 questions that rahmed has given us - they're not unit 1 right? Because i dont have a clue about either one!

Reply 31

asadtamimi

Also, this morning i finished revisiong mitosis - can some people post questions for me to answer on mitosis, thanx in advance

Regards, Asad

Reply 32

rahmed

asadtamimi

Those 2 questions that rahmed has given us - they're not unit 1 right? Because i dont have a clue about either one!

They are GCSE level.

Reply 33

rahmed

iceman_jondoe

See attached took me a long time rahmed i hope your prepared to mark it !. dunno if is right though

]

You actually did it! Lol, some people and their passion for biology :p:

i will mark it in a minute

LOL GCSE...joker

answers

(a) State two substances which would be present in a higher concentration in the umbilical vein than in the umbilical artery. (2)

(b) The cavity labelled X contains maternal blood. Suggest why it is an advantage for this blood to be in a cavity rather than in a vessel. (2)

(Total 4 marks)

Don't really need the diagram for this