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Biology questions help (1 Viewer)

SadCeliac

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do you want to chuck these on the general bio discussion thread too, that way we can have more opinions (from people who are also on the thread lol)

ill give some responses for these now :)
 

SadCeliac

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18) this question was stupid ass my teacher didn't give us a clear explanation on why but if i remember correct the answer is C or A??? idfk that one

19) pretty sure it's A because that's showing metaphase II before the chromosome pairs get pulled apart into chromatids (and total 2n=6)

20) I think it's A because if you look at Trait A, all of them have a high rate which would mean low genes and high environment (seeing as the adopted kids have the trait too), also Trait B, the adopted have low but the twins have high therefore high genes and low environment, and the Trait C it's low/low because genes don't give a high percentage and also adopted kids are very low
 

Big_Kev

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18) this question was stupid ass my teacher didn't give us a clear explanation on why but if i remember correct the answer is C or A??? idfk that one

19) pretty sure it's A because that's showing metaphase II before the chromosome pairs get pulled apart into chromatids (and total 2n=6)

20) I think it's A because if you look at Trait A, all of them have a high rate which would mean low genes and high environment (seeing as the adopted kids have the trait too), also Trait B, the adopted have low but the twins have high therefore high genes and low environment, and the Trait C it's low/low because genes don't give a high percentage and also adopted kids are very low
Yuh so for 18 we wanna find the individual (out of ABCD) common to both coz the stimulus explains how this person (who committed the crime) would have DNA from both (I & II). We know that II directly descends from B, so we wanna trace person B's lineage towards the left of the tree. Now we know that A is only related to person I, but not person II so we can eliminate that guy 🔫
Now we see that B's DNA is also present in C - but the thing here is that C MARRIES INTO the family lineage of person I, meaning that C doesnt share direct DNA with person I. But since C's wife shares DNA with I, when C and his wife have a kid, it becomes the COUSIN D (direct relative of I) and thus we can conclude that D shares DNA with both I and II
 

salihaaaaa66

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18. The individual who committed the crime has SNPs from 2 individuals. These 2 individuals do not have SNPs in common. This means that there are 2 separate families/lineages with unique SNP DNA.
What is one possible way someone can have SNPs from 2 separate families? Through the families breeding together. Remember gene flow? It's the exchange of DNA between populations. In this case, our populations are the 2 families.

Now, we're looking for someone whose DNA/SNPs are inherited from both families. The only person who has this is Person D.

19. The somatic cell has 6 chromosomes. So, 2n = 6 and n = 3.
Metaphase 1: Chromosomes are in pairs and there can only be 6 chromosomes present. So, we eliminate C as it has 12 chromosomes.

Metaphase 2: Chromosomes are present in a singular line. There can only be 3 chromosomes present. So, we eliminate D as it has 6 chromosomes present in metaphase 2.

Remember what homologous chromosomes are? They're chromosomes with a similar structure. We eliminate B as those chromosomes are not homologous.

Hence, we are left with A.

20. Identical twins have DNA that's very similar to exact. Siblings have similar DNA, and adoptive siblings have less genetic similarity. So, with that in mind:
With Trait B, we see that there is a very high correlation between the identical twins, and dramatically less correlation as genetic similarity decreases. This trait is strongly influenced by genetics. For example, let's assume your favourite colour is determined by your genetics. The identical twins would have very similar favourite colours, whereas the adoptive siblings would have different colour choices. Because the adoptive siblings have such a low correlation in comparison to the identical twins, the environment doesn't really play a role here.

With Trait A, the gap is quite small between the identical and adoptive siblings, so genes don't have a significant impact. But all groups have a high correlation, so the environment plays a key role here. For example, let's assume the house you were raised in strongly determines your food preferences. Regardless of your genes, if you grow up in a house that loves having chicken every week, you will grow to like chicken. This is why there is a strong correlation between all the groups, as it is the environment causing this correlation.

With Trait C, there is little to no correlation. No strong correlation gap exists between identical and adoptive siblings, indicating genes don't play a significant role. There's also no strong correlation among all the groups, so the environment doesn't play a significant role either. For instance, hypothetically imagine all those siblings were raised in the same household. Now, I ask them what their favourite music is, and they all give vastly different answers. I can then conclude that music preference doesn't correlate with genes or the family environment they grew up in.
hi there do you have a biology exam that covers absolutely every dot point and offer tutoring? i really need that band 6
 

SadCeliac

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hi there do you have a biology exam that covers absolutely every dot point and offer tutoring? i really need that band 6
just a suggestion (no hate) but why dont you just go through papers and try find each dot point through questions - that way youre both practicing and actively recalling the syllabus
i dont think there even exists a paper with every dot point in it... that would be too long 😅
 

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