BCHS 317 Klastoets / BCHS 317 Class Test 1
22 Februarie 2018 / 22 February 2018
Totaal / Total: 50
Tyd / Time: 75 minute / 75 minutes
Vraag 1 / Question 1
Lees elke vraag deeglik en kies dan die antwoord wat die beste pas.
Read every question carefully and select the answer you feel fits best.
1.1.
DNA stringe loop _____ ten opsigte van mekaar.
DNA strands run _____ in relation to each other.
a. antiparallel
b. parallel
c. loodreg / perpendicular
d. beide a en b / both a and b
[1]
1.2.
Wanneer DNA polimerase `n nuwe DNA string sintetiseer, skryf die DNA poli3merase in `n _____
When synthesizing a new DNA strand, DNA polymerase writes _____
a. 5’  3’
b. 3’  5’
c. 3’  5’ en / and 5’  3’
[1]
1.3.
Die _____ bevat _____
The _____contains _____
a. Leidende string; Okazaki fragmente / Leading strand; Okazaki fragments
b. Sloerende string; Okazaki fragmente / Lagging strand; Okazaki fragments
c. Leidende string; topoisomerase / Leading strand; topoisomerase
d. Sloerende string; replikasie vurk / Lagging strand; replication fork
[1]
Vraag 2 / Question 2
Is die volgende stellings waar of vals? Indien vals, gee die korrekte feit.
[6]
2.1. Die funksie van die histoon proteïen, H1, is om 100 bp DNA by die kern oktameer struktuur te voeg om sodoende
nukleosome met mekaar te verbind.
2.2. Een van die domeine van die SMC nie-histoon proteïen is die DNA binding en ATPase domein
2.3. Tydens sitokinese word die selkern in twee verdeel.
2.4. Tydens metafase word die chromosome in `n lyn op die ewenaar van die sel gerangskik
Are the following statements true or false? In the case of a false statement give the correct fact.
[6]
2.1. The function of the histone protein H1 is to add 100 bp of DNA to the core octamer structure to link consecutive
nucleosomes
2.2. One of the domains of the SMC non-histone protein is the DNA binding and ATPase domain
2.3. During cytokinesis the cell nucleus is divided into two separate nuclei
2.4. During metaphase the chromosomes are arranged in a line along the equator of the cell
1
Vraag 3 / Question 3
Pas elke term by sy ooreenstemende definisie.
Match every term to its corresponding definition.
[8]
3.1. DNA polimerase / DNA polymerase
a.
3.2. Eksonuklease / Exonuclease
b.
3.3. DNA helikase / DNA helicase
c.
3.4. Replikasie vurk / Replication fork
d.
3.5. Primase
e.
3.6. Enkel string binding proteïene (SSB) / Single stranded
binding proteins (SSB)
f.
3.7. Topoisomerase
g.
3.8. DNA ligase
h.
Ensiem wat die ddDNA heliks afwen deur
waterstof bindings te breek / enzyme that opens
up the double helix by breaking hydrogen bonds
Heg DNA fragmente saam deur fosfodiester
binding tussen nukleotiede / joins DNA
fragments together by forming phosphodiester
bonds between nucleotides
Ensiem wat nukleotiedes byvoeg volgens die
basis-paring reels / enzyme that adds
nucleotides according to the base-pairing rules
Ensiem wat RNA voorvoerders byvoeg tydens
DNA replikasie / enzyme that adds primers
during DNA replication
Is verantwoordelik vir die afwen en opwen van
die DNA stringe om te verhoed dat die DNA koek
of te styf opwen. / unwinds and rewinds DNA
strands to prevent the DNA from becoming
tangled or supercoiled.
Die twee gebiede wat vorm wanneer die dubbel
heliks skei tydens DNA replisering / the two
areas formed when the double helix separates
during DNA replication
Verhoed dat die afgewende enkelstring DNA
weer aan sy komplementêre string vasheg
tydens DNA replikasie / Prevents the opened
DNA strands from reannealing during DNA
replication
`n groep ensieme wat nukleotied basisse
verwyder vanaf die einde van die DNA ketting /
a group of enzymes that removes nucleotide
bases from the end of the DNA string
Vraag 4 / Question 4
Menslike DNA se totale lengte is 2 m, maar tog word al die DNA ingepas in `n kern met `n deursnee van 5 m. Verduidelik
hoe DNA verpak word in die eukariotiese sel.
[5]
Although human DNA has a total length of 2 m, it is packaged into a nucleus that is 5 m in diameter. Explain how DNA
is packaged into the eukaryotic cell.
[5]
Vraag 5 / Question 5
Gee ‘n kort beskrywing van ‘n tipiese eukariotiese selsiklus.
Give a brief description of a typical eukaryotic cell cycle.
[6]
[6]
Vraag 6 / Question 6
Verduidelik hoe sikliene en Cdks die sel siklus reguleer.
Explain how cyclins and Cdks regulate the cell cycle.
[5]
[5]
2
Vraag 7 / Question 7
Verduidelik breedvoerig die verskil in die proses van DNA replisering tussen die leidende string en die sloerende string.
[8]
Thoroughly explain the difference in the proses of DNA replication between the leading strand and the lagging strand.
[8]
Vraag 8 / Question 8
Beskryf die meganisme van werking van DNA-polimerases wat betrokke is by DNA string sintese.
Describe the mechanism of action of DNA polymerases involved in strand synthesis?
[3]
[3]
Vraag 9 / Question 9
Verduidelik die funksie van die ,  en  subeenhede wat deel uitmaak van die E. coli DNA polymerase III holo-ensiem
kompleks.
[3]
Explain the function of the ,  en  subunits that form part of the E. coli DNA polymerase III holo-enzyme complex. [3]
Vraag 10 / Question 10
In die eukariotiese replisoom, wat is die funksie van die volgende ensieme:
In the eukaryotic replisome, what is the function of the following enzymes:
10.1. Polimerase  / Polymerase 
10.2. PCNA
10.3. RNaseH
3
[3]
[3]