OCR Biology F214
Biology discussion, revision, exam and homework help.
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Re: OCR Biology F214its faster , and there are no ethical objections and lowers risk of infection , less rejection from the immune system of body(Original post by ds4143)
Nope sorry was for andrew, I didnt realise that I wasnt quoting who I was replying too, trying to get used to this app on my phone
Oh and a question for you.. what are the advantages of using genetically modified bacterua to produce insulin instead of extracting then from aninals?
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Re: OCR Biology F214I hope so! I know everything pretty much, it's just that I have a hard time understanding some of the questions as they can be fairly obscure or I answer the questions from a different perspective(Original post by ds4143)
Aw, I didnt do too well in my unit 5 exam in Jan..in fact i didnt do well at all haha, im resitting boths unit >.< are you ready for unit 4?
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Corrrrreeeccttt!(Original post by otrivine)
its faster , and there are no ethical objections and lowers risk of infection , less rejection from the immune system of body
got a question for me?
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Re: OCR Biology F214What is the role of kupffer cell (2)(Original post by ds4143)
Corrrrreeeccttt!
got a question for me?
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Wow thats the same problem I have. I guess practising questions is the only way to overcome it ahh. But its good you know your stuff atleast(Original post by DoctorVertigo)
I hope so! I know everything pretty much, it's just that I have a hard time understanding some of the questions as they can be fairly obscure or I answer the questions from a different perspective

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Kupffer cells break down old red blood cells in the sinusoid, producing bilirubin? Im not quite sure..(Original post by otrivine)
What is the role of kupffer cell (2)
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Re: OCR Biology F214you will get 1/2 you got the mark for breakdown but you forgot mentioning recycling of red blood cells(Original post by ds4143)
Kupffer cells break down old red blood cells in the sinusoid, producing bilirubin? Im not quite sure..
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Oooooh okay thanks(Original post by otrivine)
you will get 1/2 you got the mark for breakdown but you forgot mentioning recycling of red blood cells
Explain the process detoxification of alcohol
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Re: OCR Biology F214right(Original post by ds4143)
Oooooh okay thanks
Explain the process detoxification of alcohol
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so ethanol is dehydorgenated by enzyme ethanol dehydroganse and forms ethanal and the ethanal can still be dehydrogenated by enzyme called ethanal dehydrogenase and forms ethanoate and can combine with coenzyme A to from acetyl coenzyme A for process of respiration and hydrogen atoms are released which is for NAD to form reduced NAD and removes any fatty acids present. -
Bam! Thats perfect!!(Original post by otrivine)
right
so ethanol is dehydorgenated by enzyme ethanol dehydroganse and forms ethanal and the ethanal can still be dehydrogenated by enzyme called ethanal dehydrogenase and forms ethanoate and can combine with coenzyme A to from acetyl coenzyme A for process of respiration and hydrogen atoms are released which is for NAD to form reduced NAD and removes any fatty acids present.
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Re: OCR Biology F214How to control insulin (6)(Original post by ds4143)
Bam! Thats perfect!!
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b-cells contains Ca and k ions channels. K ion channels are open and Ca channels are closed. K ions move out of the cell so that it has a resting potential of -70mV. As blood glucose conc increases, glucose diffuses into the cell. Glucose is used in respiration inside the cell, producing ATP. Increase in ATP cause K ion channels to shut. Therefore cells becomes less negative. This causes Ca ion channels to open. Ca floods in, causing vesucles containg insulin to fuse with the b-cell membrane. Indulin moves out by exocytosis.(Original post by otrivine)
How to control insulin (6)
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Re: OCR Biology F214i think you will get 4/6 you got a bit muddled here with ionic movements , the correct stages for getting those 6 marks are(Original post by ds4143)
b-cells contains Ca and k ions channels. K ion channels are open and Ca channels are closed. K ions move out of the cell so that it has a resting potential of -70mV. As blood glucose conc increases, glucose diffuses into the cell. Glucose is used in respiration inside the cell, producing ATP. Increase in ATP cause K ion channels to shut. Therefore cells becomes less negative. This causes Ca ion channels to open. Ca floods in, causing vesucles containg insulin to fuse with the b-cell membrane. Indulin moves out by exocytosis.
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1) the cell membrane consisits of Na and K ion channels
2)K ion channels are open and move into the cell
3)K ions move from a region of high conc to low conc and glucose is metabolised to ATP
4)ATP causes the K ion channels to close and changes potential difference
5)calcium ion channels open and the ion causes the vesicles containing insulin to fuse with the cell surface membrane releasing insulin by exocytosis
tell me if i made mistake somewhere -
Ohh I dont think thats right because k ions moves out just like at resting potential of a neurone, if you remember that? And i wasnt too sure about the Na and K channels, but I just checked the book now page 26, its does only say that the b-cells has Ca and K ion channels.(Original post by otrivine)
i think you will get 4/6 you got a bit muddled here with ionic movements , the correct stages for getting those 6 marks are
1) the cell membrane consisits of Na and K ion channels
2)K ion channels are open and move into the cell
3)K ions move from a region of high conc to low conc and glucose is metabolised to ATP
4)ATP causes the K ion channels to close and changes potential difference
5)calcium ion channels open and the ion causes the vesicles containing insulin to fuse with the cell surface membrane releasing insulin by exocytosis
tell me if i made mistake somewhere
From your point 4 onwards is correct..
So just to make sure..
1) b-cells has Ca and K ion channels. K ions move out of the cell causing a potential difference of -70mV
2) when glucose in the blood increase, it moves into the cell via diffusion.
3) glucose is quickly respired, producing ATP, an increase in ATP causes k channels to shut. Cell becomes less negative.
4) depolarisation causes Ca channels to open, Ca enters, vesicles containing insulin, fuses and releases i.sulin by exocytosis
There you go
you were close 
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Re: OCR Biology F214yes yessssss sorry my mistake(Original post by ds4143)
Ohh I dont think thats right because k ions moves out just like at resting potential of a neurone, if you remember that? And i wasnt too sure about the Na and K channels, but I just checked the book now page 26, its does only say that the b-cells has Ca and K ion channels.
From your point 4 onwards is correct..
So just to make sure..
1) b-cells has Ca and K ion channels. K ions move out of the cell causing a potential difference of -70mV
2) when glucose in the blood increase, it moves into the cell via diffusion.
3) glucose is quickly respired, producing ATP, an increase in ATP causes k channels to shut. Cell becomes less negative.
4) depolarisation causes Ca channels to open, Ca enters, vesicles containing insulin, fuses and releases i.sulin by exocytosis
There you go
you were close 
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my turn -
Re: OCR Biology F214true(Original post by ds4143)
Hehe its all good, its better you make that mistake now rather than in the exam ^.^
Okay ...explain the differences between exocrine and endocrine glands. (2)
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endocrine is where molecules are released directly into blood and has no duct
Exocrine gland is where molecules are released and carried in duct to where they are used. -
Perfect!(Original post by otrivine)
true
endocrine is where molecules are released directly into blood and has no duct
Exocrine gland is where molecules are released and carried in duct to where they are used.
except im not quite sure about using the word 'molecules'..it may be fine to use it...but if you want..I think you should use hormones, just to be on the safe side..but if your defo sure about molecules then thats fine 
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Re: OCR Biology F214checked the book now in their definition they used molecules as well(Original post by ds4143)
Perfect!
except im not quite sure about using the word 'molecules'..it may be fine to use it...but if you want..I think you should use hormones, just to be on the safe side..but if your defo sure about molecules then thats fine 
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What is the name given to when it slightly overshoots polarize (1) -
Ooohh okay(Original post by otrivine)
checked the book now in their definition they used molecules as well
What is the name given to when it slightly overshoots polarize (1)
Hyperpolarisation
Suggest why fish can excrete ammonia but mammals must convert it to urea for excretion.
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got a question for me?
