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Biology B3 predictions - Edexcel 20 June 2016

Anyone have any ideas on what could come up this year? Possible six markers? I thought maybe a six marker linked to animal or plant communication/co-evolution as they've never done a six marker on that?

Reply 1

Mermaidqueen

I think there might be a 6 marker on the structure of a nephron, it seems suitable

Reply 2

1990jo123

Original post by Mermaidqueen

I think there might be a 6 marker on the structure of a nephron, it seems suitable

Yess I think its going to be the nephron structure. They have never asked on the nephron structure

Reply 3

forever.studies

http://www.thestudentroom.co.uk/showthread.php?t=4158273&p=65917694#post65917694

Reply 4

forever.studies

Thanks for the predictions

Reply 5

TSR778899

14 minutes ago

Report post
What is a culture medium and how is that different to a culture?

Also with the fungus fusarium, is it used to produce mycoprotein or is it mycoprotein and needs to be put into a fermenter to grow it?

Also why does Fusarium need to respire aerobically?

Reply 6

glowanti

Original post by TSR778899

What is a culture medium and how is that different to a culture?

culture medium is what the microorganisms are actually grown in whereas culture is the suitable conditions for their growth.

Also with the fungus fusarium, is it used to produce mycoprotein or is it mycoprotein and needs to be put into a fermenter to grow it?

mycoprotein is made from fusarium fungus - so its the fusarium in the fermenter

Also why does Fusarium need to respire aerobically?

oxygen is a factor it needs to grow/multiply successfully, so remember when in a fermenter if it needs oxygen then sterile air is fed through the spargar at the bottom of the fermenter (the spargar is a perforated metal disk) the air is sterile because it needs to be done in aseptic conditions

Hope this helps!

Reply 7

TSR778899

Original post by caitlinford3

Hope this helps!

Thanks this was very helpful

Reply 8

hegsm1

Hi, if the structure of the nephron did come up, would we need to mention the specific names of the tubes and loops, like loop of Henle? Or just describe ultrafiltration, reabsorption etc in detail? Because I know the processes really well, but I don't quite know how to mention the loops and that into it. Good luck everyone :smile:

Reply 9

J__

Original post by hegsm1

Yes, just like the involvement of the glomerulus and the bowman's capsules in ultrafiltration, mention the sizes of molecules - that only small sized molecules diffuse into the nephron. Then the selective reabsorption of water (dependent on ADH levels), salts & all of the glucose. And include the structures where reabsorption occurs - the loop of Henlé and the convoluted tubules. Then finally talk about the release of waste substances (urea, excess water etc) through the collecting duct, then the ureters, into the bladder and past through the urethra as urine. Just talk about this but in more detail :biggrin:

Good luck for tomorrow!

Reply 10

hegsm1

Original post by J__

Good luck for tomorrow!

Really appreciate all of that :biggrin:

Thank you so much! You too :smile:

Reply 11

J__

Original post by hegsm1

Really appreciate all of that :biggrin:

Thank you so much! You too :smile:

No problem, its helping me with my revision as well! :biggrin:

Reply 12

SamhaddMi786

Has anyone got the perfect answer about co-evolution and structure of nephron? (just in case if there is a six marker on it)

Reply 13

TSR778899

what is crown gall and leaf discs when talking about agrobacterium tumefacians?? Someone please help ASAAAP

Reply 14

kb12345

A nephron is collection of thousands of microscopic tubules present in the kidney
There are 3 stages of how the kidney filters urea and other substances out of the blood.

1) Filtration
Blood travels through the renal artery and reaches to the glomerulus. The blood contains urea (solid made in the liver where amino acids react with co2 to make urea) ,water,glucose,red blood cells and proteins. The glomurulus is a network of capillaries and is present inside the bowmans capsule. The bowmans capsulle has tiny holes to let small molecules pass through like urea,glucose,water. These small molecules then diffuse into it and go through the convoluted tubules and henlest tube. The larger molecules like the red blood cells and glucose stay in the blood and are taken by the renal vein towards the heart.

2) Selective reabsorption of glucose and excess water
While the fluids flow through the convoluted tubules some useful substances like glucose and the water get reabsorbed back into the blood. Almost all glucose and all water molecules are reabsorbed. This is called selective reabsorption. The amount of water reabsorbed depends on how much the body needs. This is called osmoregulation

3) Removal of excess water in urine
At the end of the nephron the urea and remaining water go to the ureter (it takes urine from kidneys to bladder). The urea dissolves in the water to form urine.

Reply 15

astronomer99

How did it go? what did everyone get for the percentage decrease?

Reply 16

➰ Lily rose ➰

Original post by astronomer99

How did it go? what did everyone get for the percentage decrease?

53%

Reply 17

SamhaddMi786

How did everyone one find B3 higher?

Reply 18

hegsm1

In the fermentation question that asked what gas is added for the growth. What was the answer? I put oxygen then changed it to nitrogen in the last 10 mins of the exam :s-smilie:

! Because oxygen is added but for respiration. But I know nitrates are added which are converted to nitrogen for growth

Reply 19

SamhaddMi786

Original post by hegsm1

In the fermentation question that asked what gas is added for the growth. What was the answer? I put oxygen then changed it to nitrogen in the last 10 mins of the exam :s-smilie:

! Because oxygen is added but for respiration. But I know nitrates are added which are converted to nitrogen for growth