VCE Biology Question Thread

[warya]

What do we need to know about stem cells?

[sunshine98]

has anyone come across a question that requires you to do a reciprocal cross? If you have , do you mind sharing it ?
I'm just curious 

[cosine]

For the two attached:

1. Answer says that they can be labelled as GMO free, but how can this be if they used the genetically modified yeast cells to produce the chymtosin enzyme in order to make the cheese ?

2. What is the MAIN reason these two are an example of convergent evolution? I knew they were convergent, but not sure why.. Is it because they evolved so separately across the world, and retain a similar underlying basic structure due to their very similar environmental habitats/selection pressures?

And if this is the case, then do they have similar structures, how is analogous structures defined? Is it defined as different structures but with same function of just similar structures but resulted from non-relatedness?

[Biology24123]

For the two attached:

1. Answer says that they can be labelled as GMO free, but how can this be if they used the genetically modified yeast cells to produce the chymtosin enzyme in order to make the cheese ?

2. What is the MAIN reason these two are an example of convergent evolution? I knew they were convergent, but not sure why.. Is it because they evolved so separately across the world, and retain a similar underlying basic structure due to their very similar environmental habitats/selection pressures?

And if this is the case, then do they have similar structures, how is analogous structures defined? Is it defined as different structures but with same function of just similar structures but resulted from non-relatedness?

The plants are not closely related but have similar features so convergent evolution has occurred. Different basic structure. Analagous structures are structures with different basic structure but similar function

[cosine]

The plants are not closely related but have similar features so convergent evolution has occurred. Different basic structure. Analagous structures are structures with different basic structure but similar function

That is so contradictory.. 'not closely related but have similar features' and then you say they have structures with 'different basic structure'?

Is analogous structures always associated with convergent evolution? What do you mean by basic structure?

[sushibun]

For the two attached:

2. What is the MAIN reason these two are an example of convergent evolution? I knew they were convergent, but not sure why.. Is it because they evolved so separately across the world, and retain a similar underlying basic structure due to their very similar environmental habitats/selection pressures?

And if this is the case, then do they have similar structures, how is analogous structures defined? Is it defined as different structures but with same function of just similar structures but resulted from non-relatedness?

I think you're right about them living separately but having the same or similar selection pressures. The definition of analogous structures is that they have similar functions but different structures and the species that share these structures don't have a recent common ancestor just like a dolphin and shark.

[Biology24123]

That is so contradictory.. 'not closely related but have similar features' and then you say they have structures with 'different basic structure'?

Is analogous structures always associated with convergent evolution? What do you mean by basic structure?

Not closely related but develop features with similar function due to similar selection pressures. Analagous structures are related to convergent evolution

[sushibun]

For the two attached:

1. Answer says that they can be labelled as GMO free, but how can this be if they used the genetically modified yeast cells to produce the chymtosin enzyme in order to make the cheese ?

Maybe cause the enzyme used to make the cheese isn't in the cheese? It just catalyses the reaction for cheese. Actually that is a funny question. Does gmo stand for genetically modified organism? The cheese isn't an organism might be a reason or the yeast's modifed genome isnt in the product. Idk just some suggestions till an expert comes around

[cosine]

I think you're right about them living separately but having the same or similar selection pressures. The definition of analogous structures is that they have similar functions but different structures and the species that share these structures don't have a recent common ancestor just like a dolphin and shark.

Is it thought of as convergent evolution is the evolution of two species that are not closely related through a common ancestor, but share similar features through same exposure to environmental conditions and selection pressures? So what does it mean by they 'have different underlying structures', does it just mean that because they did not evolve from the same ancestor, they have developed similar structures but their basic structure is different because they do not share the same ancestral phylogeny?

[cosine]

Are these correct:

- Primates -> Hominoids -> Hominids -> Hominins -> Humans?
- All hominins are bipedal? Well only hominins alive today are humans, but are all the extinct/ancestral hominins bipedal?
- Are ONLY hominins bipedal? (in terms of VCE)

Do we need to know:

- Which primates fall under the categories of hominoids, hominids and hominins?
- All the hominin ancestors of humans?
 

[warya]

Are these correct:

- Primates -> Hominoids -> Hominids -> Hominins -> Humans?
- All hominins are bipedal? Well only hominins alive today are humans, but are all the extinct/ancestral hominins bipedal?
- Are ONLY hominins bipedal? (in terms of VCE)

Do we need to know:

- Which primates fall under the categories of hominoids, hominids and hominins?
- All the hominin ancestors of humans?

Not sure about the other stuff but 'hominin' basically means upright/walking, so yeah I think hominins were all bipedal

[warya]

Difference b/w retroviruses and adenoviruses as methods for gene transfer? Examinable?

[StupidProdigy]

With allergy immunotherapy/desensitization, how is it possible to inject doses of the allergen without the response becoming triggered? Thanks

[warya]

In regard to the difference b/w allopatric speciation and speciation, my notes say that in AS-different mutations accumalate which allows different allele frequencies to develop, whereas in S-genetic differences accumalate
Is this correct, and if so, what is the difference b/w accumalation of different mutations vs genetic differences?

[sushibun]

Is it thought of as convergent evolution is the evolution of two species that are not closely related through a common ancestor, but share similar features through same exposure to environmental conditions and selection pressures? So what does it mean by they 'have different underlying structures', does it just mean that because they did not evolve from the same ancestor, they have developed similar structures but their basic structure is different because they do not share the same ancestral phylogeny?

Yep, that's what I think