Statements below showz xqj 5f26zjg5 m49lju three double-stranded nucleotide sequences. Which of these sequences of base pairs is possiujj5jq692xl4 zfgm5z ble in a DNA molecule?

I. 5’- GGA CAG AGC -3’
3’- CCT GTC TCG -5’


II. 5’- GGA CAG AGC -3’
3’- TTC ACT CTA -5’


III. 5’- AGG GAC CGA -3’
3’- TCC CTG GCT -5’

  The diagram below shows the structure based on the tetranucleotide hypothesizz; poo66rygg(he/ lu 7qo+b9s proposed by Levene that DNA was made up of equal amounts of adenine, guanine, cytosine and thymine. This hypothesis was a problem of induction, because it was based on a limited set of data. Subsequ 9+ (h6z ro/6qzg7e oou;yplbgent evidence and data revealed a more complex and accurate understanding of the structure, leading to the falsification of the initial hypothesis.

  What is the main role ofhsv5veq7kw8eh:c k 3 ck1p; *p the ribosomes labelled in the micrograph?

  A strand of nucleotides reads CCUAGAGCUUACCG. Which type of pentose sugar cw,i (yckqop 2:ould be found in the nucleocp :oy,wqk2i(tides in this strand?

  Which of the following processes is most directly involved in the forma+h q(9 hf1ovtwa4 u5w d24x6sdzb nspbgb9 8f(tion of nucleic acibsgdbnw24v f9h(a(9osw4 t 5uhp 6q1b8dxz f+ds such as DNA?

  What distinguishes uracil from thw/ eee0*b7 -uiob1c 8me6mbnhymine?

  Which statements are characteristics of a DNA mol yq)/;zrnqqv36z1 o:vlu,uuk ecule?
I. The two strands are identical.
II. The two strands are antiparallel to one another.
III. The sugar-phosphate backbone is held together by covalent bonds.

  The table shows the nucleotide base sequence aq ow dv2mty.yo-7; i*knd genome size (number of base pair*qoytw yk7.i2v o d;-ms, bp) for different species.

Which conclusion can be drawn, based on the table?

  How does the genetic code provide evidence of universasyh.328pjsb 5w/( iakp xsa4v l common ancestry?

  The diagram depicts nucleosomccfg; ,w0zh)w; oh5jq es.

Gel electrophoresis is a technique often used to analyse DNA moleculest be)i :e.azm 6k1p(ti. It includes a gel at zeba6e:.ipit)mk( 1nd an electric field. The diagram below shows the outcome of gel electrophoresis.


1.DNA is a type of nucleic acid. State one location where DNA is found in cells.

2.Deduce, with a reason, which direction the DNA fragment moves through the gel.

3.Distinguish between the functions of DNA and RNA in unicellular organisms.

  The diagram below shows pre-mRNA a*8p0dkvsub+ hhi mu +,nd three mature mRNA transcripts where the introns have be+h8idp*,ub +m v hk0usen removed.



What is an advantage of the above process?

  Which of the following is a similarity between transcription and tranfkk .zn*,q1 mrslation?

  The diagram shows the structure of a DNA fragment. loh2: nghk7orzrrk e+,n29 ml*-8 lvcWhich bonds easily break and ref rrkhm +9nv*7 k z-82r :nll2olgeo,hcorm?

  What would make one DNA molecu739j2: x2is.,yfcxe oepe gc xle more stable than another DNA molecule?
I. More G-C base pairs than A-T base pairs
II. More hydrogen bonds between base pairs
III. Greater distance between A-T base pairs than G-C base pairs

  Hershey and Chase conducted an experiment to invei93z 09q. vnb wuux(vestigate whether DNA or protein serves as the genetic material. They cultured 2 batches of viru0 bewuz9vi (9uqxnv3 .ses, one in a medium containing radioactive $^{35}S$ and one in radioactive $^{32}P$. They then introduced each batch of viruses to separate cultures of bacteria. After allowing time for the viruses to infect the bacteria, the culture solutions were centrifuged to separate the viral remains from the bacterial cells, forming two layers, the pellet and the supernatant.


Which component of the tube would provide evidence that DNA is the genetic material?

  Which function and pru8lk4ro5:eq /y k y syp(g5qk/ocess are correctly matched in the table below?

  Which statement highlights2l mbe4wd: l7rn;31yt,):;y cwkoszy :icoh y the importance of nucleosomes in DNA supercoiling ?

  The image shows many ribosomes on a mRNA mp:/ 4e01zsxuocic)tx olecule. How many unique polypeptide chains areop 40su :cc 1tezx/i)x being translated?

  Which of the labelled structures shows the correcxs +bnnhy ez5;.i73av 6 quon/t directionality of the DNA molecule? 5+/e.n n3uh qxo;nviay bs67z

The diagram below showr492 i7g/2cbff6 xfnqdop 0mgs the structure of DNA nucleotides.

1.State the component of DNA that is attached at position X.

2.Identify the type of bonding shown as dotted lines in the diagram.

3.The 5’ and 3’ linkages in DNA play an important role in replication, transcription and translation.

3.1.On the diagram, label the 5’ prime and 3’ prime ends on both strands to show the direction of the DNA.

3.2.Outline how the processes of transcription and translation occur with regards to the formation of 5’ and 3’ linkages.

4.Explain how the DNA helix maintains its stability.

5.Erwin Chargaff’s data on the relative amounts of purine and pyrimidine bases played an important role in determining the structure of DNA.

5.1.Outline how Chargaff’s data contributed to our understanding of the structure of DNA.

5.2.State a proposed model of DNA that was falsified by Chargaff's data.

The Hershey-Chase experimen(/eeirrm 4 ;3 x*idr:)d ljhakt in 1952 involved cultured viruses that were radioactively labelled withdra lxh)m (*3djkri/4 eie:;r either sulfur ($^{35}$S) or phosphorus ($^{32}P) in two separate flasks. Each batch of viruses was then added to separate cultures of bacteria. After allowing time for the viruses to infect the bacteria, the culture solutions were centrifuged to separate the viral remains from the bacterial cells, forming two layers, the pellet and the supernatant.


1.State reasons for using radioactive sulfur ($^{35}$S) and phosphorus ($^{32}$P).

2.Suggest one technological development, other than radioisotopes, that helped open up possibilities in understanding the overall structure of DNA.

3.1.Outline the results of the experiment that provided evidence to support the conclusion that DNA is the genetic material.

3.2.Describe how the 4 nitrogenous bases of DNA enables polypeptides to be coded for.

4.Explain how DNA can be packaged into compact units to form chromatin.

  What bases are P, Q, and R if S ismt(gb17hnof;n p) 7um a pyrimidine?

  How did radioisotopes help make the investigationsu fzbx5 lq**13v92d+dc wxr:me nm7iw by Hershey and Chase possible?92wbcfqux+7 er diz15mm:l*v n 3xd* w

  What feature of the DNA molecule was utilised by Hershey and Chase in o+ez7lmkq)s5e d05w gg rder to identify that viral DNA is able to enter 5d m5)+sk7zqewe 0gglhost cells, but most of their protein is not?

.

The image below shows a short fragment of the DNA mc*)zcik /w- 3ru kggs54* brjzolecule.



1.Suggest one possible outcome if DNA consisted of two parallel strands instead of two antiparallel strands.

2.The structure of DNA is described as being a 'double helix'. Explain how this structure is related to the DNA function.

3.Compare and contrast the nitrogenous bases thymine and uracil.

  Which of the following shows the correct components of gl0:g du1+ dkfone nucleosome?

  Hershey and Chase conducted experiments using the radioactive isotopesq n)dx z65q pdxuw8*/wk/pv+s $^{35}$S and $^{32}$P which demonstrated that DNA is the genetic material. What would they have observed about the distribution of isotopes in the centrifuged sample if protein, rather than DNA, were the genetic material?

  The graph below shows the resum ;vd iqgrh z*:s.hoyf59 n0a0lts of an experiment conducted by a team of researchers investigating the9y: hm*riav fq5.sohg0d;n0z relationship between the composition and melting point of different DNA samples. At the melting point, the DNA double helix separates into two individual strands.

Two DNA samples were compared, one consisting of only PQ pairs and another one consisting of only RS pairs. Letters P, Q, R and S represent different nitrogenous bases found in the DNA.


Based on the results presented in the graph, and your knowledge of nucleotide base pairing (between purines and pyrimidines), deduce which nitrogenous bases correspond to the letters P, Q, R and S.

DNA and RNA are nucleicoy9pgv01 r2)y e ;)of g (v6nakokp*cc acids that are essential to all living organisms.
1.Draw and label a diagram of a nucleotide.

2.Explain how the variation in base sequences leads to the ability of DNA to have an enormous capacity for storing genetic information.

3.DNA is a polymer of nucleotides. Describe the structure of DNA.

The image below shows a short fragment of the DNA moleculeh 6q09-pbdlsx*ypniu :s *gq: .


1.Suggest one possible problem that could arise if DNA consisted of two parallel strands instead of two antiparallel strands.

2.State one place where DNA is found in cells.

3.Compare and contrast the structure of DNA and RNA.