VCE Biology Question Thread

[Butterflygirl]

Also another thing,

for natural selection, is it necessary to say at the end "Allele frequency of favoured phenotype increases, allele frequency of phenotype selected against decreases"?

I never have space left to add it in, but if its crucial then I'd add it in.

[Angelx001]

What do we have to know about the lymphatic system?

[plsbegentle]

What do we have to know about the lymphatic system?

not much i think..
-b and t cells reside in lymph nodes
-fluid from tissues drains into lymph vessels
-clonal expansion occurs in lymphatic system, so that's why in immune responses, lymph nodes are swollen.

[esthertham58]

just to clarify-

regulator genes becomes repressors right?

[esthertham58]

Hey guys,

I think I need some clarification on gene regulation. All I now know is that you have repressor proteins binds to the upstream region of a gene and that prevents RNA polymerase from performing the function of transcription. Therefore the gene cannot be expressed and is turned off. Is that all I need to know about gene regulation? Thanks!

Does it play a part in cell differentiation or other functions?

[HasibA]

can someone briefly rehash the inputs and outputs for all stages of respiration
and the light independent and dependent stages (like very simply)
thank u guys <3, always confuse this

[vox nihili]

Hey guys,

I think I need some clarification on gene regulation. All I now know is that you have repressor proteins binds to the upstream region of a gene and that prevents RNA polymerase from performing the function of transcription. Therefore the gene cannot be expressed and is turned off. Is that all I need to know about gene regulation? Thanks!

Does it play a part in cell differentiation or other functions?

This is a pretty good way of looking at regulation. There are also things that can turn on genes too, in much the same way

It plays a part in basically all cell functions, but the differences between individual cells are largely the consequence of differences in gene expression patterns. For example, every cell has the gene for insulin, but only one cell type in the body will produce is (beta-cells in the Islets of Langerhans).

[The Usual Student]

Hey guys,

I think I need some clarification on gene regulation. All I now know is that you have repressor proteins binds to the upstream region of a gene and that prevents RNA polymerase from performing the function of transcription. Therefore the gene cannot be expressed and is turned off. Is that all I need to know about gene regulation? Thanks!

Does it play a part in cell differentiation or other functions?

that is all you need to know! legit!
And know why its useful: so we dont spend energy synthesising useless proteins

[esthertham58]

This is a pretty good way of looking at regulation. There are also things that can turn on genes too, in much the same way

It plays a part in basically all cell functions, but the differences between individual cells are largely the consequence of differences in gene expression patterns. For example, every cell has the gene for insulin, but only one cell type in the body will produce is (beta-cells in the Islets of Langerhans).

Thanks for replying! So can I say that different cells have different repressors? ( Depending on the cell function)

[esthertham58]

that is all you need to know! legit!
And know why its useful: so we dont spend energy synthesising useless proteins

Thanks!

[vox nihili]

Thanks for replying! So can I say that different cells have different repressors? ( Depending on the cell function)

That's correct, yep.

[plsbegentle]

can someone briefly rehash the inputs and outputs for all stages of respiration
and the light independent and dependent stages (like very simply)
thank u guys <3, always confuse this

sure.
Gylcolysis
Input: ADP, NAD+, glucose
Output: ATP, NADH, pyruvate
Kerb cycle
Input: acetyl coA, NAD+,FAD,ADP
Output: CO2, NADH,FADH2, ATP
ETC:
Input:02, FADH2,NADH,ADP
Output: 34-36 ATP, water
 
Light dependent
Input: water, NADP,ADP
Output: 02,NADPH,ATP
Light indepdent
Input:C02,NADPH,ATP
Output: glucose, NADP,ADP

guys let me know if im missing something!

[Springyboy]

guys let me know if im missing something!

I think you're missing adp as an output for the ld photosynthesis stage but other than that with a quick skim it's looking right.

[vox nihili]

sure.
Gylcolysis
Input: ADP, NAD+, glucose
Output: ATP, NADH, pyruvate
Kerb cycle
Input: acetyl coA, NAD+,FAD,ADP
Output: CO2, NADH,FADH2, ATP
ETC:
Input:02, FADH2,NADH,ADP
Output: 36-38 ATP, water
 
Light dependent
Input: water, NADP,ADP
Output: 02,NADPH,ATP
Light indepdent
Input:C02,NADPH,ATP
Output: glucose

guys let me know if im missing something!

34-36 (the other two overall come from glycolysis!)

[hodang]

Affected fathers will have daughters with the trait but none of their sons has this trait.

So mothers do not have to give the affected trait to all of their sons aswell? In an X-linked dominant trait, only affected fathers must pass the affected trait to their daughters? How about for X-linked recessive?

Ps- Thanks for answering