VCE Biology Question Thread

[The Usual Student]

Attached a table
hope it helps

Also, when formulating a hypothesis, do we need to include the IV and DV? and ect?

[sunshine98]

but what if you hypothesizes that nothing will occur lol or do we just stick with something happening ?

That's confusing because saying nothing will occur is the same as saying it will not occur. But because u will most likely encounter questions whereby you are testing the occurrence of a process , I guess you will most likely say in your hypothesis  that something will happen.

Also, when formulating a hypothesis, do we need to include the IV and DV? and ect?

No. Your hypothesis should be a simple straightforward statement that is either going to be supported or rejected by the results of your experiment.But when you do some of your sacs and later exams the questions will be something like state the IV and DV , so its not something u can neglect.

[The Usual Student]

That's confusing because saying nothing will occur is the same as saying it will not occur. But because u will most likely encounter questions whereby you are testing the occurrence of a process , I guess you will most likely say in your hypothesis  that something will happen.No. Your hypothesis should be a simple straightforward statement that is either going to be supported or rejected by the results of your experiment.But when you do some of your sacs and later exams the questions will be something like state the IV and DV , so its not something u can neglect.

hmm ok I came in with the mindset that a scientific experiment is all about testing the relationship between the IV and the DV and how they effect each other, that is why I though a hypothesis saying that, for instance, temperature does not increase volume of water ( as a random example ), could be a possible hypothesis but since a hypothesis must be POSITIVE that isn't allowed ? Sorry I am just kinda confused,

Or is the point of the experiment to test the hypothesis, hence, having a hypothesis that says nothing willl happen is kinda pointless?

[sunshine98]

hmm ok I came in with the mindset that a scientific experiment is all about testing the relationship between the IV and the DV and how they effect each other, that is why I though a hypothesis saying that, for instance, temperature does not increase volume of water ( as a random example ), could be a possible hypothesis but since a hypothesis must be POSITIVE that isn't allowed ? Sorry I am just kinda confused,

Or is the point of the experiment to test the hypothesis, hence, having a hypothesis that says nothing willl happen is kinda pointless?

my bad I thought you meant explicitly stating the IV and DV and actually writing IV and DV, but you are absolutely correct
Also I don't think you have to say it in the positive its just better (from what I was taught) maybe someone else can clarify.

[The Usual Student]

my bad I thought you meant explicitly stating the IV and DV and actually writing IV and DV, but you are absolutely correct
Also I don't think you have to say it in the positive its just better (from what I was taught) maybe someone else can clarify.

ahhh ok! Thanks!!

[TheAspiringDoc]

1) They have more C-H bonds that can be broken for energy
2) As soon as you see only  C, H, O you can narrow down your options to  carbohydrates or lipids. The six-sidedness clarifies that its a carbohydrate as well as the fact that its in the 1:2:1 ratio. The ratio is something  you should know about carbohydrates or you may have learnt that the empirical formula is this- CnH2nOn ( glucose as an example which is C6H12O6 where n=6)
3) you can think of it as one water molecule to each bond. When u think about it the number of bonds is always one less than the number of monomers (try it with smaller numbers , a polymer with 10 monomers has 9 bonds hence 9 water molecules). So you would need 99 water molecules

^^keep in mind that that formula only applies to monosacchaides. Due to dehydration synthesis reactions which are involved in the formation of glycosidic bonds in polysaccharides, H2O molecules are 'lost' into the surroundings resulting in a different ratio.

P.S.

Spoiler

Guys I'm back I missed you and daym it's so relieving to be on these forums again!!!!! Long live AN!!!!

[The Usual Student]

^^keep in mind that that formula only applies to monosacchaides. Due to dehydration synthesis reactions which are involved in the formation of glycosidic bonds in polysaccharides, H2O molecules are 'lost' into the surroundings resulting in a different ratio.

P.S.

Spoiler

Guys I'm back I missed you and daym it's so relieving to be on these forums again!!!!! Long live AN!!!!

These forums are not the same without you lol,

[TheAspiringDoc]

Hey

A few Unit 4 AoS1 questions if anyone would be so kind as to help

-If introns are 'non-coding segments of DNA', then how does it make sense for 'alteranative exon/intron splicing' to affect gene regulation and protien products (as long as the same exons are retained obviously )

-intuitively, why do chromosomes condense during prophase and remain so until telophase?

-does it count as a nonsense mutation if the 'met' (start) base triplet in DNA is mutated and that effectively stops the translation of the protein before its synthesis ever even begins?

Thank you!!

[TheAspiringDoc]

I've been reading up on DNA, and although I'm defs no expert in this stuff I've had a little bit of a funny idea.

The general consensus is that the non-coding regions of DNA are just junk/remnants/protective measures against mutations in the coding regions of DNA. However, my thought is that perhaps this non-coding DNA could actually be lying in wait for further evolution?

Now I know that we do have genes that do things like code for wings and stuff, but the're just not activated (right?  ), but what if we were to want to evolve a completely new, never-seen-before type structure? perhaps all these regions of non-coding are like susceptible or something to such mutations?

Obviously this ain't my strong point LOL so I'm kinda hoping to put it out there for discussion, but yah, I just thought this was an interesting idea

[Butterflygirl]

Can someone please help me with this question.

Why is it advantageous for starch and glycogen to be large and not soluble?

The answer talks about grains being formed. I'm confused because I thought glycogen was water soluble, and starch was not.

Help is highly appreciated. >.<

[geminii]

Hey everyone, I have a question - it would be awesome if someone could tell me which of these match up with the other.

1. Facilitated diffusion
2. Active transport
3. Bulk transport (endocytosis and exocytosis)

and they each need to be matched up with one of these...

1. Substances which are small can pass rapidly through pores in the lipid bilayer. These substances must:

• be polar/soluble in water
• uncharged

Examples are water, and gases such as carbon dioxide and oxygen.

2. Lipid soluble substances which readily pass through the lipid layer. These substances must:

• be non-polar

Examples are steroids and fatty acids.

3. Substances which are too large for the pores, or not lipid soluble by nature, or charged, may pass through protein channels. The substances must:

• be polar

Examples are monomers, which go through carrier proteins, and ions, which go through channel proteins.


It would be great if someone could help match each description with its name! Thanks



ALSO (sorry for so many questions, haha) can anyone list the properties that substances MUST have in order to undergo the following (through a cell membrane):

• Diffusion
• Osmosis
• Facilitated diffusion
• Active transport
• Bulk transport (endocytosis + exocytosis)

Thanks once again everyone!!

[purplegiraffe]

What are the inputs of the electron transport chain?

[Photon]

Can someone please help me with this question.

Why is it advantageous for starch and glycogen to be large and not soluble?

The answer talks about grains being formed. I'm confused because I thought glycogen was water soluble, and starch was not.

Help is highly appreciated. >.<

Basically starch and glycogen are both forms of energy being stored, and if they were soluble then instead of them clumping up together to form grains (which would then be a lot easier to store for the body) they would dissolve with the cytoplasm of the cell. This would be chaotic because they would interfere with metabolic processes happening inside the cell.

No, both glycogen and starch are insoluble in water.

[Photon]

What are the inputs of the electron transport chain?

NADH, FADH₂, ATP and Oxygen

[Biology24123]

Hey everyone, I have a question - it would be awesome if someone could tell me which of these match up with the other.

1. Facilitated diffusion
2. Active transport
3. Bulk transport (endocytosis and exocytosis)

and they each need to be matched up with one of these...

1. Substances which are small can pass rapidly through pores in the lipid bilayer. These substances must:

• be polar/soluble in water
• uncharged

Examples are water, and gases such as carbon dioxide and oxygen.

2. Lipid soluble substances which readily pass through the lipid layer. These substances must:

• be non-polar

Examples are steroids and fatty acids.

3. Substances which are too large for the pores, or not lipid soluble by nature, or charged, may pass through protein channels. The substances must:

• be polar

Examples are monomers, which go through carrier proteins, and ions, which go through channel proteins.


It would be great if someone could help match each description with its name! Thanks



ALSO (sorry for so many questions, haha) can anyone list the properties that substances MUST have in order to undergo the following (through a cell membrane):

• Diffusion
• Osmosis
• Facilitated diffusion
• Active transport
• Bulk transport (endocytosis + exocytosis)

Thanks once again everyone!!

ah Only number 3 matches up with facilitated diffusion. The rest do not