HSC Biology Marathon 2015 (3 Viewers)

[DepressedPenguino]

q: State the probability of a second child of greta and gary inherting the allele

 

[BlueGas]

View attachment 32044

q: State the probability of a second child of greta and gary inherting the allele

Are you sure this pedigree is correct? Because if two non-affected parents produce an affected offspring (In this case, Gary and Greta are the unaffected parents, and Karen is the affected offspring), the trait is recessive because one of the parents must hold the recessive trait. So let's assume any of the parents, Gary or Greta are "Bb", because they can't be "BB" (If one of them was BB, then none of the children would have the trait) and they can't be "bb" (If one of them was bb, then they would be shaded, but none of the parents, Gary or Greta are shaded). So if Gary or Greta are 'Bb" then Karen should not be affected because if you use a punnet square, the first child in F1 would not be affected.

 

[DepressedPenguino]

Are you sure this pedigree is correct? Because if two non-affected parents produce an affected offspring (In this case, Gary and Greta are the unaffected parents, and Karen is the affected offspring), the trait is recessive because one of the parents must hold the recessive trait. So let's assume any of the parents, Gary or Greta are "Bb", because they can't be "BB" (If one of them was BB, then none of the children would have the trait) and they can't be "bb" (If one of them was bb, then they would be shaded, but none of the parents, Gary or Greta are shaded). So if Gary or Greta are 'Bb" then Karen should not be affected because if you use a punnet square, the first child in F1 would not be affected.

I dont think there is a problem with the pedigree. Cant both gary and greta be Bb? So 25% of their offspring is affected which Karen is part of.

 

[BlueGas]

I dont think there is a problem with the pedigree. Cant both gary and greta be Bb? So 25% of their offspring is affected which Karen is part of.

If both parents were Bb, then the first child would be BB but Karen has to be bb because Karen is affected.

 

[BlueGas]

Ah, the answer is 0%, am I right?

 

[DepressedPenguino]

Ah, the answer is 0%, am I right?

Nop lol

 

[BlueGas]

Nop lol

It has to be, because if one of the parents were BB, then none of the children would be affected, so as a result, both parents have to be Bb, this results in BB, Bb, Bb, bb, and since the child already has the disease, then the next child would definitely not inherit the disease so there's a 0% chance of the next child inheriting (if that makes sense).

 

[useless stick]

Heres an easy one, what is enantiostasis? And provide an example of a plant that undergoes this as well as its adaptations.

 

[BlueGas]

Heres an easy one, what is enantiostasis? And provide an example of a plant that undergoes this as well as its adaptations.

Enantiostasis is the maintenance of metabolic and physiological functions in response to variations in the environment. An example of a plant would be the mangroves. Their adaptations include salt excretion, (salt is excreted from the underside of the leaves), salt exclusion (salt is excluded from special glands in the leaves) and salt accumulation (salt is accumulated on old leaves that drop off).

 

[BlueGas]

Which of the following definitions of transgenic organisms is correct?

A) They are created when the DNA from an organism of one species is inserted into the DNA of an organism of another species
B) They are hybrids produced when a male and a female from different species interbreed
C) They are produced as a result of mutation
D) All of the above

 

[brianchau3]

It's not B as DNA isn't specific to gender and hence not D. Mutations are generally the altering of a bases (whether it be a deletion, addition or substitution) in the organism itself, which I don't think involves transgenic organisms. I think A is most correct, as transgenic organisms involve introducing DNA from one organism into the DNA of another, altering the genetic make up of the organism.

 

[BlueGas]

HSC Question: During protein synthesis, mRNA is translated into sequences of amino acids. How many amino acids are coded for in this molecule?

Answer is 2 but why? Is it because there is a codon and an anti-codon so that makes it two? Can someone explain for me?

 

[DepressedPenguino]

HSC Question: During protein synthesis, mRNA is translated into sequences of amino acids. How many amino acids are coded for in this molecule?

Answer is 2 but why? Is it because there is a codon and an anti-codon so that makes it two? Can someone explain for me?

Which year?

 

[BlueGas]

Which year?

Honestly not sure, I've got the 2008 success one edition and it has questions from modules in order and the past papers, this question is from the modules in order and it doesn't say the year if you know what I mean.

 

[DepressedPenguino]

Honestly not sure, I've got the 2008 success one edition and it has questions from modules in order and the past papers, this question is from the modules in order and it doesn't say the year if you know what I mean.

Is that the exact wording of the question that u posted?

 

[BlueGas]

Is that the exact wording of the question that u posted?

Yeah, question is worded exactly from the book.

 

[DepressedPenguino]

Yeah, question is worded exactly from the book.

Well the question is wrong in the first place.. mRNA does not get translated into amino acids and the number of amino acids that a mRNA strand codes for depends on the no. of codons that it has

 

[Rhinoz8142]

A new product has been developed to kill pathogens in drinking water.

Design an experiment to test the effectiveness of the product (4)

 

[BlueGas]

Well the question is wrong in the first place.. mRNA does not get translated into amino acids and the number of amino acids that a mRNA strand codes for depends on the no. of codons that it has

Isn't an amino acid basically mRNAs binded with tRNAs? As in the codon of a mRNA binds with an anti-codon of a tRNA, and this basically forms an amino acid?

 

[DepressedPenguino]

Isn't an amino acid basically mRNAs binded with tRNAs? As in the codon of a mRNA binds with an anti-codon of a tRNA, and this basically forms an amino acid?

Nop. Aminocyl- tRNA synthetase binds an amino acid to the tRNA with the specific anticondon. The tRNA joins its anticodon with the corresponding codon of the mRNA and this process repeats with the amino acid molecule(s) being transferred from the previous tRNA to the next