Biology: Discussion, Questions & Potential Solutions

[Yacoubb]

Yikes, the ATAR notes book really let me down on that plant defence question, all it says is that chemicals can be used kill pathogenic organisms but not any specific examples. 

Also what did everyone put down for the 3 organelles involved in transport of protein around the cell? I could only think of endoplasmic recticulum and golgi body. I suppose nucleolus might have been acceptable??

I did rough ER and golgi and I wasn't too sure about the last one, I did mitochondria for providing ATP. But it did say 'directly involved' and I don't know if its direct. Some of my friends did plasma membrane and vesicles for the third one.

Not too sure because I don't have the question but mitochondria may be accepted. It has been alluded to in past questions (VCAA 2012 exam 2) as a component of protein synthesis. Nucleus would also have been an answer.

[Anne Boleyn]

Hey guys for the “describe at a molecular level how excess apoptosis occurs(or something like that)” question
I wrote a mutation occurred in the regulatory gene that controls the production of a death ligand, resulting in the overproduction of this molecule. I’m not sure if that’s correct though???

[darkz]

Hey guys for the “describe at a molecular level how excess apoptosis occurs(or something like that)” question
I wrote a mutation occurred in the regulatory gene that controls the production of a death ligand, resulting in the overproduction of this molecule. I’m not sure if that’s correct though???

I hope that is, cause that's what I wrote haha

[Thurmanator]

Hey guys for the “describe at a molecular level how excess apoptosis occurs(or something like that)” question
I wrote a mutation occurred in the regulatory gene that controls the production of a death ligand, resulting in the overproduction of this molecule. I’m not sure if that’s correct though???

There's probably going to be multiple accepted answers for that question given that it said "suggest". I wrote about an excess production of signalling molecules that induce apoptosis in a nearby cell, probably won't get me full marks, but hey, I can't do anything about it now.

Also for everyone asking about the very last question with the other possible explanations about the results I would bet my life that it's:

• One type of algae may have had a faster rate of cellular respiration
• The pigment in the red algae may have diffused into the solution

[jinaede1342]

Hi, I'm just wanting to ask about the first question in section B. I think I've misread the question, was the question asking us to describe transcription or translation? :/ Also what did people get for the phylogenetic tree question about convergent evolution? Thanks in advance!

[darkz]

Hi, I'm just wanting to ask about the first question in section B. I think I've misread the question, was the question asking us to describe transcription or translation? :/ Also what did people get for the phylogenetic tree question about convergent evolution? Thanks in advance!

Translation. I just picked two similar ones e.g. the shark and dolphin cause they were similar length, cartilaginous, not common recent ancestor and similar diet

[jinaede1342]

Ahh yes, I did the exact same thing. Hopefully it's correct. Thanks! 

[hannahsayce]

Hi, I'm just wanting to ask about the first question in section B. I think I've misread the question, was the question asking us to describe transcription or translation? :/ Also what did people get for the phylogenetic tree question about convergent evolution? Thanks in advance!

I did the humpback whale and the shark whale because they both developed structures for filtering krill however were on the two different phylogenetic trees thus not resulting from a common ancestor... is that right?

[darkz]

I did the humpback whale and the shark whale because they both developed structures for filtering krill however were on the two different phylogenetic trees thus not resulting from a common ancestor... is that right?

Yeh, that should be fine. (Sharks are fish, while dolphins are mammals. So I suppose anyone who did Shark + Dolphin + plausible reason should get the 2 marks for convergent evolution). Conversely, for divergent, should be two fish or two mammals I'd say.

[Hirul1280]

I wrote down phytoalexins and defensins for the plant chemicals
Also, the organelles for export I wrote were Rough ER, Golgi apparatus and secretory vesicles

Not sure if secretory vesicles are organelles but Mitochondria perhaps (since exocytosis is Active transport)?

[Hirul1280]

Hey guys for the “describe at a molecular level how excess apoptosis occurs(or something like that)” question
I wrote a mutation occurred in the regulatory gene that controls the production of a death ligand, resulting in the overproduction of this molecule. I’m not sure if that’s correct though???

I thought the premise of this question was an 'Auto-immune' disorder (self-intolerant), Cytotoxic T cells would release cytokines (then outlined the extrinsic pathway)

[darkz]

Not sure if secretory vesicles are organelles but Mitochondria perhaps (since exocytosis is Active transport)?

Secretory vesicles would count

I thought the premise of this question was an 'Auto-immune' disorder (self-intolerant), Cytotoxic C cells would release cytokines (then outlined the extrinsic pathway)

Both seem like valid answers

[MAGGOT]

I wrote down phytoalexins and defensins for the plant chemicals
Also, the organelles for export I wrote were Rough ER, Golgi apparatus and secretory vesicles

Instead of vesicles I said cell membrane 🤷‍♀️

[jainamhs_]

Hey everyone!

I’m a new user to AtarNotes, but I just wanted to ask a couple questions about the exam which I’m still unsure / anxious about...

1) For the organelles involved in exocytosis, could you have also written ribosome (some people are saying it is meant to be explicitly involved in transport of the polypeptide)

2) When it asked how uncontrolled apoptosis is possible, is it alright to say an error in T-helper cells that caused them to detect identical antigens on similar cells of a tissue as non-self (then NK and Tc cells come into play)

3) In the social implications for the vitamin A rice, would it be alright to mention that consumers may be wary of genetically modified foods (kind of a stigma) even though it wasn’t mentioned? And also, would a social implication for Bt corn be that people of lower socioeconomic status are forced to handpick crop and sustain rashes for a living?

4) What would’ve been appropriate responses for the very final short answer question - why is keeping the tubes in the dark a control, and what are two possible explanations?

Thanks in advance!

[sarahzz]

Hey guys!

1.What did you guys write for the question asking about structural features of the transitional fossil?

2.What were chemical barriers for a plant? I wrote shedding of infected leaves etc. and the plant producing toxins, but not sure if this is right..