VCE Biology Question Thread

[cooperbailey14]

Do we need to know about the peripheral and central nervous system and stimulus response model in regard to the CNS, such as touching something hot?

[PhoenixxFire]

Do we need to know the temperatures for the stages of DNA Hybridisation? Ik they are picky about it for PCR but surely not DNA Hybridisation....

It's the same - 55 degrees, because that's when the DNA strands are able to join pack into double stranded DNA. In hybridisation the melting temperature will change so you don't need to remember that.

Do we need to know about the peripheral and central nervous system and stimulus response model in regard to the CNS, such as touching something hot?

Nope

[Bri MT]

Do we need to know the temperatures for the stages of DNA Hybridisation? Ik they are picky about it for PCR but surely not DNA Hybridisation....

To add on to PFs response, you should know what higher temperature for DNA to separate means in terms of species relatedness

[darkz]

Why do we analyse conserved genes e.g. cytochrome C instead of non-coding regions? (For determining evolutionary relationships)

[cooperbailey14]

Why do we analyse conserved genes e.g. cytochrome C instead of non-coding regions? (For determining evolutionary relationships)

Non-coding regions are not expressed in an organisms phenotype and therefore are not analysed with molecular techniques.

[EllingtonFeint]

What are differences in phenotype between hominins and great apes?

What exactly would you write for the overall ATP yield for aerobic respiration. Would 30-38 ATP be okay...? I think Douchy said something like that?

[Erutepa]

Why do we analyse conserved genes e.g. cytochrome C instead of non-coding regions? (For determining evolutionary relationships)

For molecular clocks between more distantly related species, cytochrome C is commonly used as it is heavily conserved meaning It will be present in essentially all cells that have mitochondria and thus will be a good gene for comparison. Cytochrome C also has a slower mutation rate then non-coding regions as natural selection acts on the cytochrome C gene selecting against some mutations that reduce fitness. This makes it good for comparison amongst more distantly related species.
however non-coding regions can also be used and offer a higher mutation rate which is useful for comparison of more closely related organisms.

What are differences in phenotype between hominins and great apes?

What exactly would you write for the overall ATP yield for aerobic respiration? Would 30-38 ATP be okay...? I think Douchy said something like that?

hominins are a tribe consisting of humans and their extinct bipedal ancestors. great apes (or hominids) is a family consisting of hominins as well as other animals like gorillas and chimps.
If you had to say one phenotypic characteristic that separated hominins from other hominids, you probably should state bipedalism (and all the morphological differences which support bipedalism like the larger heel bone, more central foramen magnum...)

Aerobic respiration actually produces 36-38, but you should choose just one to write (so i have heard)

[jarrahs]

I vaguely remember seeing a question on this somewhere but I can't remember the answer.

After a B or T cell is activated does it proliferate or differentiate first?

[C14M8S]

The purpose of the change in pelvis shape in humans is just to improve the centre of gravity for bipedalism, right?

[Erutepa]

The purpose of the change in pelvis shape in humans is just to improve the centre of gravity for bipedalism, right?

Also to allow for more big-brained babies.

[PhoenixxFire]

I vaguely remember seeing a question on this somewhere but I can't remember the answer.

After a B or T cell is activated does it proliferate or differentiate first?

Doesn't matter for VCE.

The purpose of the change in pelvis shape in humans is just to improve the centre of gravity for bipedalism, right?

Yep. Also makes it more efficient (which a consequence of improving the centre of gravity)

[briv01]

The purpose of a change in pelvis size from narrower to a more broader and taller pelvis is to-
- enable for bipedal locomotion
-allow for a more even weight distribution to support bipedalism by standing upright . this can support things such as running

[jarrahs]

What exactly does the term 'carrying angle' refer to and what is a good way to describe why it is beneficial to bipedalism?

[C14M8S]

Would the rough evolution of life on earth look a little something like this?
Prokaryotes -> Photosynthetic prokaryotes -> Aerobic prokaryotes -> Eukaryotes -> Multicellular Organisms -> Plants -> Chordates -> Fish -> Amphibians -> Reptiles -> Mammals -> Birds -> Flowering plants

[jarrahs]

What exactly does the term 'carrying angle' refer to and what is a good way to describe why it is beneficial to bipedalism?

It's the angle of the femur relative to the vertical of the body. It means that the body has to move less when walking, as it takes less movement to position all the weight over one leg. Also means we can easily stand on one leg.