VCE Biology Question Thread

[nerdmmb]

Are germ-line cells the same as germ cells?

Yupp

[RazzMeTazz]

Is independent assortment only in reference to the random arrangement of homologous chromosomes at the equator of the cell in metaphase 1 of meiosis 1?

Or could it also be considered to include the random opposite directions of the cell, that the sister chromatids of the duplicated chromosomes are facing (which have experienced crossing over and hence recombinations on their chromatids) in metaphase 2 of meiosis 2?

[RazzMeTazz]

Does the term 'homologue' refer to one homologous chromosome or a pair of homologous chromosomes?

[vox nihili]

Does the term 'homologue' refer to one homologous chromosome or a pair of homologous chromosomes?

It refers to something that is the same as the thing you're talking about.

[RazzMeTazz]

Do all prokaryotes have a single circular chromosome or is this just bacteria?

[nerdmmb]

Do all prokaryotes have a single circular chromosome or is this just bacteria?

All prokaryotes

And some even have additional DNA fragments known as plasmids.

[Stressedyear11here]

In mitosis, how long are each stages?
I'm guessing anaphase, telophase, metaphase, prophase?

Cheers.

[nerdmmb]

Why is one X chromosome inactivated in females during growth and development?

Also, out of curiosity, is there such a thing as a haploid organism? If so, can someone please provide an example of one?


Thanks!

[RazzMeTazz]

If a greater number of chromosomes for a particular species, indicates greater complexity, how come butterflies have a larger chromosome number than humans?

Are butterflies more complex than humans? :O

[vox nihili]

In mitosis, how long are each stages?
I'm guessing anaphase, telophase, metaphase, prophase?

Cheers.

It varies from organism to organism, cell to cell. Certainly not info you need for year 12.

Why is one X chromosome inactivated in females during growth and development?

Also, out of curiosity, is there such a thing as a haploid organism? If so, can someone please provide an example of one?


Thanks!

A lot of genes on the X chromosome are only needed during development. A double dose of them after the early stages of development can lead to developmental defects and other issues. Many genes are actually deactivated on one chromosome because of this. Otherwise you get too much stuff and that can be dangerous. It just so happens that most X-linked genes fall into this category. If the chromosome weren't disabled, you'd see some serious differences between males and females (larger than the ones we already see).

Yes, there are haploid organisms. Fungi and male bees are good examples.

If a greater number of chromosomes for a particular species, indicates greater complexity, how come butterflies have a larger chromosome number than humans?

Are butterflies more complex than humans? :O

This is definitely something you need to know for VCE: a great number of chromosomes does not indicate greater complexity. Nor does a great number of genes. There is, however, a correlation between the size of the proteome and complexity.

[Rishi97]

I've read somewhere that bees reproduce via mitosis. So does that mean there is no "variation" within bees? They are all the same?

[RazzMeTazz]

In reference to chromosome numbers for a particular species, what does the 'n' represent?

Would it just be representing the haploid number of chromosomes for that species?

And any number in front of that for eg: '2n' would just represent how many full sets of chromosomes that species has?

[Rishi97]

In reference to chromosome numbers for a particular species, what does the 'n' represent?

Would it just be representing the haploid number of chromosomes for that species?

And any number in front of that for eg: '2n' would just represent how many full sets of chromosomes that species has?

I would say that the n represents the number of different types of chromosomes.

[vox nihili]

I've read somewhere that bees reproduce via mitosis. So does that mean there is no "variation" within bees? They are all the same?

They kind of do a bit of both. I can't remember the exact details, but there was an exam question on this a little while ago. You didn't really need to know anything about bees, just be creative with your genetics.

[Rishi97]

They kind of do a bit of both. I can't remember the exact details, but there was an exam question on this a little while ago. You didn't really need to know anything about bees, just be creative with your genetics.

Thanks...i was just intrigued tro find out the answer so if anyone know's please tell me