VCE Biology Question Thread

[dankfrank420]

when pyruvate is converted into lactic acid, is any atp released?

Yeah 2 ATP

[shivaji]

Yeah 2 ATP

oh ok. i did a neap paper (in the smartstudy guide) and they said 0 ATP was released, so yeh

[melons]

Was doing a NEAP trial paper and I came across this question... lost all four marks on it. I simply can't understand what each reaction is and I have never seen a diagram like this... is this similar to what VCAA would provide? Also could someone explain the answers?

(Image removed from quote.)

Reaction A is cellular respiration and B is photosynthesis. Hopefully, you get which is catabolic/anabolic etc from that.
Molecule X is something released in respiration and needed in photosynthesis...so CO2 makes sense, but I don't get why it can't be water (maybe because water is an input in cellular respiration too?).
Condensation reactions are ones where smaller molecules are joined to form bigger ones, so B and C.

[mahler004]

oh ok. i did a neap paper (in the smartstudy guide) and they said 0 ATP was released, so yeh

Yeah 2 ATP

No, just NAD+ (which then feeds back into glycolysis.)

Reaction A is cellular respiration and B is photosynthesis. Hopefully, you get which is catabolic/anabolic etc from that.
Molecule X is something released in respiration and needed in photosynthesis...so CO2 makes sense, but I don't get why it can't be water (maybe because water is an input in cellular respiration too?).
Condensation reactions are ones where smaller molecules are joined to form bigger ones, so B and C.

A condensation reaction is where two smaller molecules are joined together to make a larger molecule, with the release of a smaller molecule (usually water.)

That question looks like it's a bit beyond the level of VCE, but anyway.

Water is required to hydrolyse ATP to give ADP + Pi, and is required in a condensation reaction to form ATP. Note that usually these waters are left off when describing glycolysis. I think it's meant to be pretty abstract - 'reaction C' and 'reaction D' can be any reactions, and you're supposed to infer that reaction A is catabolic because it's making ATP, and reaction B is anabolic because it' using ATP. They don't have to be photosynthesis and glycolysis (although they can be.) Molecule X is just needed in reaction  C and D - it's not shown as needed in the two reactions A and B, so CO2 can't be the answer.

[shivaji]

in the electron transport chain, is it 34 ATP that is produced, or is it 32 ATP?

[katiesaliba]

in the electron transport chain, is it 34 ATP that is produced, or is it 32 ATP?

Depends on the cell. I think muscle cells typically produce 36 ATP where as skeletal cells produce 34 ATP.

[ValiantIntellectual]

How does anaerobic respiration create the bi products it does? For example lactic acid

[Reus]

in the electron transport chain, is it 34 ATP that is produced, or is it 32 ATP?

Just write 32-34 ATP produced.

[katiesaliba]

How does anaerobic respiration create the bi products it does? For example lactic acid

Lactic acid fermentation in humans: NADH becomes NAD+ and pyruvate becomes lactate. It's similar in plants, however ethanol is produced among some other differences. I suggest googling 'fermentation' looking through the images.

[shivaji]

NADH becomes NAD+

isn't NADH and NAD+ the same?

[katiesaliba]

Nope...NAD+ is reduced to NADH

[RazzMeTazz]

Are two individuals considered to be of the same species if they can interbreed or if they can interbreed to produce viable offspring?

Because the lion and tiger can interbreed to produce the sterile liger but we don't really count the lion and tiger as the same species do we?

[shivaji]

Are two individuals considered to be of the same species if they can interbreed or if they can interbreed to produce viable offspring?

Because the lion and tiger can interbreed to produce the sterile liger but we don't really count the lion and tiger as the same species do we?

if any two individuals can produce VIABLE and FERTILE offspring, then they are of the same species

[kk.08]

Does anyone have a good way or technique to remember the different plant hormones and their effects? I especially get confused between the effects of cytokinin and gibberellins.

[katiesaliba]

I struggle to remember these, but I always associate gibberellins with overall plant growth, as they both start with G :') It's handy in multiple choice questions. However, I second your question.