VCE Biology Question Thread

[melons]

Why do the products of anaerobic respiration differ between animal and plant cells?

[howlingwisdom]

Why do the products of anaerobic respiration differ between animal and plant cells?

I think it's because of the the fact that there are different enzyme pathways in animal and plant cells which result in different products (lactic acid in animals, ethanol and carbon dioxide in plants/fungi)

[melons]

I think it's because of the the fact that there are different enzyme pathways in animal and plant cells which result in different products (lactic acid in animals, ethanol and carbon dioxide in plants/fungi)

Thank you!

[Reus]

Why do the products of anaerobic respiration differ between animal and plant cells?

Anaerobic respiration is used by few microorganisms which use an inorganic acceptor like Sulfur and does not utilize oxygen or pyruvate and derivatives of pyruvate. Depending upon the end product anaerobic respiration is of two types:

Glucose→ 2 ethanol + 2CO2 + 6ATP

(alcohol is the product; commonly occurs in plants like yeast)

Glucose→ 2 lactic acid + 2ATP
(animals)

[Reus]

Why is gene regulation necessary? I know it's necessary as protein synthesis requires energy, but what else?
Thanks

[Scooby]

Why is gene regulation necessary? I know it's necessary as protein synthesis requires energy, but what else?
Thanks

Synthesising proteins unnecessarily wastes energy, like you said. Also, say the gene encodes a protein hormone. We might want that hormone synthesised and secreted only at specific times, say, in development (eg. you wouldn't want the hormones that trigger puberty being produced in an infant). Production and release of a protein may have harmful consequences if inappropriate, which is another reason why gene regulation is important

[Reus]

Thanks scooby.

Another inquiry, what causes/is responsible for the splicing of exons into a mRNA molecule?

[Scooby]

Thanks scooby.

Another inquiry, what causes/is responsible for the splicing of exons into a mRNA molecule?

Exons aren't "spliced in", they just aren't excised like introns are (well, they can be, but the introns are always excised). Introns are excised (and occasionally exons) by a complex called a spliceosome

[Reus]

Exons aren't spliced "in", they just aren't spliced out like introns are (well, they can be, alternative splicing blah blah). Introns are spliced out (and occasionally exons) by a complex called a spliceosome

Haha oops, that's what I meant! So it's spliceosome? Cause my teacher said it was RNA ligase and something else (guessing she referred to spliceosome)?

And why is only one of the two strands in a DNA called a template strand?
Thanks.

[alchemy]

Haha oops, that's what I meant! So it's spliceosome? Cause my teacher said it was RNA ligase and something else (guessing she referred to spliceosome)?

And why is only one of the two strands in a DNA called a template strand?
Thanks.

Yes, spliceosomes are involved in the removal of introns.
The template strand refers to the strand that is actively being transcribed into mRNA. Therefore, the sequence of bases on it serve as a 'template' for the mRNA. The template strand is also known as the anti-sense strand. The other strand of DNA which isn't being transcribed to mRNA is called the sense strand.

[RazzMeTazz]

What is the 'satellite' on a chromosome?

[RazzMeTazz]

How do the terms 'spindle' 'centrosome' and 'centriole' all link to one another?

[Reus]

Yes, spliceosomes are involved in the removal of introns.
The template strand refers to the strand that is actively being transcribed into mRNA. Therefore, the sequence of bases on it serve as a 'template' for the mRNA. The template strand is also known as the anti-sense strand. The other strand of DNA which isn't being transcribed to mRNA is called the sense strand.

Thanks alchemy. 

[alchemy]

Thanks alchemy. 

No problem 
I need to start answering bio questions again haha

[grannysmith]

So during prophase, the chromatin condenses and there is a total of 46 chromosomes and 92 chromatids. Sister chromatids are joined at the centromere and are identical.
Do each of the 46 chromatids duplicate during the "S" phase of interphase, resulting in 92 chromatids?