The Student Room Group

OCR Biology F214

Scroll to see replies

Reply 20
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 :tongue:

Oh and a question for you.. what are the advantages of using genetically modified bacterua to produce insulin instead of extracting then from aninals?

This was posted from The Student Room's Android App on my HTC Desire HD A9191


its faster , and there are no ethical objections and lowers risk of infection , less rejection from the immune system of body
Reply 21
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?

This was posted from The Student Room's Android App on my HTC Desire HD A9191


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 :frown:
Reply 22
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


Corrrrreeeccttt! :biggrin: got a question for me?

This was posted from The Student Room's Android App on my HTC Desire HD A9191
Reply 23
Original post by ds4143
Corrrrreeeccttt! :biggrin: got a question for me?

This was posted from The Student Room's Android App on my HTC Desire HD A9191


What is the role of kupffer cell (2)
Reply 24
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 :frown:


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 :smile:

This was posted from The Student Room's Android App on my HTC Desire HD A9191
Reply 25
Original post by otrivine
What is the role of kupffer cell (2)


Kupffer cells break down old red blood cells in the sinusoid, producing bilirubin? Im not quite sure..

This was posted from The Student Room's Android App on my HTC Desire HD A9191
Reply 26
Original post by ds4143
Kupffer cells break down old red blood cells in the sinusoid, producing bilirubin? Im not quite sure..

This was posted from The Student Room's Android App on my HTC Desire HD A9191


you will get 1/2 you got the mark for breakdown but you forgot mentioning recycling of red blood cells
Reply 27
Original post by otrivine
you will get 1/2 you got the mark for breakdown but you forgot mentioning recycling of red blood cells


Oooooh okay thanks :smile:

Explain the process detoxification of alcohol

This was posted from The Student Room's Android App on my HTC Desire HD A9191
Reply 28
Original post by ds4143
Oooooh okay thanks :smile:

Explain the process detoxification of alcohol

This was posted from The Student Room's Android App on my HTC Desire HD A9191

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.
Reply 29
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.


Bam! Thats perfect!!

This was posted from The Student Room's Android App on my HTC Desire HD A9191
Reply 30
Original post by ds4143
Bam! Thats perfect!!

This was posted from The Student Room's Android App on my HTC Desire HD A9191

How to control insulin (6)
Reply 31
Original post by otrivine
How to control insulin (6)


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.

This was posted from The Student Room's Android App on my HTC Desire HD A9191
Reply 32
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.

This was posted from The Student Room's Android App on my HTC Desire HD A9191


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
Reply 33
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


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 :biggrin: you were close :smile:

This was posted from The Student Room's Android App on my HTC Desire HD A9191
Reply 34
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 :biggrin: you were close :smile:

This was posted from The Student Room's Android App on my HTC Desire HD A9191


yes yessssss sorry my mistake :colondollar:
my turn
Reply 35
Original post by otrivine
yes yessssss sorry my mistake :colondollar:
my turn


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)
This was posted from The Student Room's Android App on my HTC Desire HD A9191
Reply 36
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)
This was posted from The Student Room's Android App on my HTC Desire HD A9191

true :wink:
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.
Reply 37
Original post by otrivine
true :wink:
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! :smile: 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 :biggrin:

This was posted from The Student Room's Android App on my HTC Desire HD A9191
Reply 38
Original post by ds4143
Perfect! :smile: 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 :biggrin:

This was posted from The Student Room's Android App on my HTC Desire HD A9191


checked the book now in their definition they used molecules as well

What is the name given to when it slightly overshoots polarize (1)
Reply 39
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)


Ooohh okay :smile:
Hyperpolarisation

Suggest why fish can excrete ammonia but mammals must convert it to urea for excretion.

This was posted from The Student Room's Android App on my HTC Desire HD A9191

Quick Reply

Latest