Statements below show three double-stranded nucleotide sequences. Which ofg8)llk -3yljhc2r0u 9n q9d4w lngcn) these sequences of base pairs is possible in -l34nnkj8rwl hcdc99gg y)02n q)l lu 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 hypipmvkmz 8wsz561p- 0b othesis 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. Subsequent evidence and data revealed a more complex and accurate understanding of the structure, leading to z-8pv1 0m5 s6wzbikmp the falsification of the initial hypothesis.

  What is the main role of the vnb fp0 my62x,ribosomes labelled in the micrograph?

  A strand of nucleotides reads CCUAGAGCUUACCG. Which type of pentose sugar cwaut vo 5,za.ah22tx /ould be found in the nucleotides in this strand?xzt voa.wu/a2 2t5h,a

  Which of the following processes is most dire.)axl 1pxo ys0ctly involved in the formation of nucleo) a lxp10yx.sic acids such as DNA?

  What distinguishes uracil from thy s3 5 h;imnwwbxbrp9))i2ds-/ b2tpcimine?

  Which statements are characteristics of a DNA mollzz9jkhe1i 89 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 anba8p1)d d)9liw,h/o +mbdjpk d genome size (number of base pairs, bp) fod+iok h9)1p wpdd/j8)ab ,blmr different species.

Which conclusion can be drawn, based on the table?

  How does the genetic code provide evidence of universal common ancestry?ch3 d 1z59-0lqiclkn:)d iwg d

  The diagram depicts nucle lx oy6 z tvc(8y6q2/1 p(-zrwrqor(yhosomes.

Gel electrophoresis is a teu*y0/z qlvm o4 ae1km0chnique often used to analyse DNA molecules. It includes a gell 4ue0ykmo ma1/v q0*z and 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 and three mature mRNA tran bk/4cw hvj3 o y))h4zvvpv0d-scripts where the introns hav)dco )bzkh4vj wvh3p-4/vy0 ve been removed.



What is an advantage of the above process?

  Which of the following is a similarity between transcription and translat kto+ /v;bsov*i ag,/+dhgpc1ion?

  The diagram shows the structure of a DNA fra , huj-ggzl2;zr(( pqbmzi..r)x:vgt gment. Which bonds easily break and reform?rl(2t;.. gbgzihp( mgjxv:z,z q -u)r

  What would make one DNA molecule more stable tho eq54e5jfuft*na 09 qv p 8mi0equx2p ow:d73an 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 experimenur) zq2 y ccmx:00/kjlt to investigate whether DNA or protein serves as the genetic material. They cultured 2 batches of viruses, 0 ) :2jxrculzqk/cym0 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 process are correctly matched in the table v(n975 zj;bxilg 2bpp below?

  Which statement highlights the importance of nucleowms63vbk ( x;a .uns6vsomes in DNA supercoiling ?

  The image shows many ribosomes on a.v 6v z56i,e o6qpem7zz(yomh mRNA molecule. How many unique polypeptide chains are bpizeeo7 6,vzo6(5 h.mzvym6qeing translated?

  Which of the labelled ni;bj **mn/ pgstructures shows the correct directionality of the DNA moleculeb* *n; ngij/pm?

The diagram below shows the jd fa/*gq; q203f un;q7kpxcostructure 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 experiment in 1952 involved cultured viruses that were raa05d. xo6 s 1l 3hoo.rf6gwrpvdioactiv3v1s oxp ldrg. oh566a.r0wfoely labelled with 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 is en t ,1z+m*mw3dttv7b ox mk0;1rxfr5a pyrimidine?

  How did radioisotopes help make the i-nj-q zk96h3hn p 9kzxnvestigations by Hershey and Chase possible?hk n h-zz-n96j9 xk3qp

  What feature of the DNA molewg16b zhy61qx;lrr b )cule was utilised by Hershey and Chase in order to identify that viral DNA is able to enter host cells, lbbhqygz6r61 );1xw rbut most of their protein is not?

.

The image below shows a sho/zu+,qc-5dw 7kpxq 56taka twccqw3:rt fragment of the DNA molecule.



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 e2g5/vzwp 5bty mb 45ycomponents of one nucleosome?

  Hershey and Chase conducted experimao0a youv;r) 4ngp9)aents using the radioactive isotopes $^{35}$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 results of an experiment conductedl pd j)jgq8(n/ by a team of researchers investigating the relationship between the composition and men lqj8djg)p (/lting 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 nucleic acids that are essential to all living organismsvb pnqxg 7r8gzr9 ++j /jq12nw.
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 mol-mmu +d75 5(znj4q kcoxzqi6+c)piqy ecule.


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.