distorxe. betoeen tco cone.cuttve.
e,that 16 ,
39. met&. Aentt, hat is
gate
than the dioensien ty a gicaltleu& (ooalg
In
potaotic., &uch as Epcoil, tho
have a
they do rt
de fioed ucles, the DNA 6 rot
sca tleved
|thhout the cel talh (heinn recoively ctarged)
beld toith &ome
potcins Cthat tove ositive crayes)
is Ceariced in tavge. loops held by paieéns.
Nuc eosome nodel:
Boposed y PDovnbevg
307homns (9a)
It is uniNexsally o(Cepted Cdel- AccCxding to this
totcel, the. thomatin is tcopOsed c a cting
pentel bended unAS caled
udeosone"
is an
utlet scres-The texs
nd
coined bs Oudet et al Neclecscre
CHa te es ditc sha ped fostcle. itha caseler
Cepies tj fous rudectorme. histunes
H, ,HB,Hy Hi
DNA:
A nsed on
ds
N
&S DN:
rumbey c
polkuclectide
ctands , DlA
types- 6s DlA (sinle. Etanded, L)
(doute stsanded DH
Eackeiophoqe E M-ts bacteibphane.
ds DNA:
Tt is
Ccomon type o DNA &een in all cuta
ic E po taptic. cellks E
al&o in soe
1even batteicphages.
B) Based on tupe
uáes Such
helix DNA 15 o ve types.
A, B,C,D E
Linear & ciculor
DNA:
Linear DNA is One in which the. erds avc
ee
irear NA DCcaxk in eutaryotic uclei- Dn pokaxypted
chlcoplast & oitochordia. the DrNA iS cicular.
I443 Pockaging b DNA helix
Taten the
diGtance. betoeen to conse. Cutive. base
O"34 no (o-su x16), if the. lergth o DAA
doutle. helit in a typical toammalian cell is Calcuote!
d CSimply by toutipljing the total umber
bP ith
Pois6
as
5 Pasine,quarine is esyinclas with yiniatne cytosine
Otio
bot
change
qtc
for a species: Tt des
speific
is
with
tissue
The vatio Can he used to identi14 the specie s, the
Yatio is iah in adanced organises E low n piolEve
Cxganiss.
EX] thuroan ver IS3, E coli 093,
T bacteiophage - 86.
Dimensions o DNA:
The dìameter D DNÐ helix
is
204 (
nm EmainS
aloost tonstant Since. each base. pair CoSist & o
One pusine
Che ysnicine aluoags.
he length D DNA clependí upen the rumber o
ucleoidek.
Each hey înclade& One ninor & Dne. major qnove
* tach tuon contains (0 bp (o) 20 nuclectide &.
|* the ange &epavaling the too auccestve nulectide
Fains is 36.
The pitch co) erqt t ench tun is 34 ef.
4 the ditance. betoeen the tae. paiYs in heltx
histores
he &e
"iGh in
a
basic
the
se Siclues cay ositive chnqes in their ece choins
einht
41Rstnes ae Oqnnised to foo a unit
tvele cules called as Nstboe. octamer. hik islene
Octame (um
helix i
aound
COYe
aout to0 tuxns. The
whkh
ds
the
udeo&ornes
bA
ae
oked
DNO molecale colled irkey DHARtex
Ol:
ypical ucleosoroe
teqetber b
lecsorval cHnSpacer
Cortalns
200 bp c
tN bel.
Gerexally DNA mates tuoo (ooplele. um& artund
Cctameves & these, too tums are sealed
the
histone
l
by H, potein
noleale. "tte asociaticn do -ve
chavgecd DNA & tve charqel istunes alcss or
inside. the. rucleus.
mearingjal DNA factagjing
Alumber
t
rucleosomes in honon, cel sX10.
Aluclecsonoe& constitute the epeatirg nit o}
abuctue in rudeu& called chomatin,thrtod- tite stained
Ccolcured) bocies Seer in ruleus. the
chunntin ax Seeo al 'beods
udecscoes in
sbing shuc ue
ohen eoed under elecbunic Micvo&cope (EM
R means
tne chain has clasty s ,the
'. In each bact bone Cstnnd) the
Othex has
hucleckids a jóned by phosrkodiester kord6 Fhaspoie
Stex bord is fouroed betiieen 3
casbon a Suqar
todecale & sh casbon o next Sucp olecule (a).
Botth stoand& ae held toqether
Weeh Cne puxine in One 6band by& kychogen konds bet.
Pimiioe on the
Cprosite Stand.
the
peene o these. hyctgen tonds 06 st
Cbéeved b
c faeuling Adenire s toureed to
thyrine by tuo hydgen bonds
CA) Geanioe t6
bounded to Cytostoe by thee bydgen kands CG:c).
AS a veSalt atunS a puune Comes
Cpposite to a
in'eine thió qreate& appuxiately enfo
distance
betueen the too stands t the helix
"tbuó, DNA doutde heliN 1e6emble& a tisted
bddex
Tthe koct tone 6 femed ty al
levately
ananged augor
E husate E the skeps
bose pais.
Chan Nule: E E chaga oted on chemical
comporent&
DNA
t Puine&
DNA
3-Puines
ds
put oavd ertain enea lisa ions
yuni dines Occus in Equal arount& în d&
RNA
DNA aTe
thyrine
4 fuine ade nine i6
atke rine éy guarine.
tosine
fyinaines
enio oith yiidie, thymire