Theo s liu tnh hnh nhim HIV trn th gii v Vit nam nh sau S ngi nhim HIV ang cn sng: 40 triu ngi Trong ngi ln 37 Triu ngi; Tr em <15 tui l 2.5 triu ngi S ngi nhim trong nm 2003 l 3 triu trong ngi ln l 2.5 triu; Tr em <15 tui l 500 nghn Vit nam tnh n 31-03-2003 s ngi nhim 73 660; chuyn sang AIDS 11254; S cht do AIDS 6325 Vy virut l g? Cu trc nh th no? Phng thc sng ra sao?
Chng III Virut - Bnh truyn nhim v Min dch Tit 30 Cu trc cc loi virut I.c im chung ca virut Theo di th nghim ca Ivanopxki (1892) Th
Th nghim ca Ivanpxki nghim ca Ivanopxki (1892) (nm 1892) L cy Nghi Dch thuc l n chit Lc qua b nn lc vi bnh Dch lc
khun Nhim Nui Soi di knh hin trn mi vo l cy trng vi quang lnh thch hc Khng thy mm Khng
thy Cy vn b Qua th nghim trn, em c nhn xt g v kch thc ca virut ? Rt nh b, nh hn rt nhiu so vi kch thc ca vi khun. Gi mm bnh l
virut Kt lun 1. Kch thc ca virut Rt nh b: Khong 10 100nm (1nm=10-4A0 = 10-6mm) - - Ch c th quan st bng knh hin vi in t Virut ln nht = 1/10 kch thc Vi khun Virut nh nht = 1/100 kch thc Vi khun 2. Hnh dng ca virut
QuaQuan quanst sthnh em thy thi mt viruts cvirut nhng sauhnh dng no? Virut di Virut HIV Virut khm
Virut vim no Virut bi lit Phage T2 Gm 3 dng c bn Hnh tr xon Virut khm
Hnh khi Virut bi Dng phi hp Virut HIV Phage Kt lun v hnh thi ca virut: Virut c 3 dng hnh thi c bn:
- Hnh tr xon: Capsome sp xp theo chiu xon ca axit nucleic - Hnh khi: Capsome sp xp theo hnh khi a din vi 20 mt tam gic u hoc dng khi cu - Hnh phc hp: V d phge u cu trc khi ui c cu trc tr xon Hnh dng ca virut do yu t no qui nh? Hnh dng do cu trc ca virut qui nh 3. Cu trc ca virut
Quan st s cu trc ca virut Li (b gen) V(capsi t) Axit nucli c Capsit Qua quan st em thy virut c cu to bi nhng thnh
phn no? Bn cht mi thnh phn l g? Li (b gen) Li( b gen): Axit V(capsi Nuclic t) Axit nucli c Capsit
V (capsit): Prtin Phc hp gm axit nuclic v prtin c gi l Nuclcapsit Nuclcap B gen ca virutB c gen im g sai ca sinh B gen
khc soca vi so vivt b nhn gen ca sinh chun virut vt nhn chun? B gen B gen (ARN) (ADN) B gen ca virut c
th l ADN hoc ARN, B gen (ADN) B gen ca sinh vt nhn chun Kt lun a. Cu to chung Virut c cu to gm hai thnh phn -Li: L mt phn t axit nucleic
B gen ca virut c th l AND hoc ARN -V (capsit): Bng protein Capsit c cu to t cc n v l capsome Kch thc ca virut ph thuc vo s lng capsome S kt hp gia axit nucleic v protein gi l NucleoCapside Virut c nhng dng cu to no? b. Cc dng cu to
Quan st s sau. Hy cho bit virut c nhng dng cu to no? Axit nuclic Capsit Virut trn (dng n gin): Cu to ch c li v v capsit V ngoi Gai
glycprt in Virut c v bc (dng phc tp) VVirut ngoi ca cvirut v c bn cht l g? N c tc dng bc g? L i Caps
it Gai glycprtin c tc Gai g ? dng lm nhim v khng glycprtin nguyn, gip virut bm trn b mt t V ngoi lp lipit kp v prtin tng t mng sinh cht bo v virut.
Virut Virut cha c cu to Virut nn cch coi lc Axit t bo a nucli mt c sng
gi l th c th mcha, c Prti vch sao? c coi l mt n dng sng c bit , gi l ht virut hay Prti HtChng virut cch cuc to
n virion. tng ng vi loi cu to tng Axit cu trc no trong nucli ng vi mt t bo sinh vt c
Nhim sc Kt lun Dng cu to trn (dng n gin): Virut cu to ch c li v v capside (ging cu to chung) Dng c v bc (cu to phc tp): C v bc bn ngoi v capsit v trn c gn cc gai Glycoprotein.
+ V ngoi c cu to gm lipit v protein ging nh mng nguyn sinh cht, c chc nng bo v + Gai glycoprotein c chc nng khng nguyn, gip virut bm trn b mt t bo. Vi cu to nh vy virut c phng thc sng nh th no? 4. Phng thc K sinh bt buc trong t sng bo
ch Vt ch m virut k sinh c T bo ng vtVirut H5N1,virut th l nhng sinh vt no ? di ch Cho v d? Thc vtVirut khoai ty,c chua Vi sinh vt
Phage T2, T4 ca E.Coli Th nghim ca Ivanpxki (nm 1892) L cy Nghin Dch thuc chit l Lc qua b nn lc vi bnh
khun Dch lc Soi di knh hin vi quang hc Nui trn mi tr ng thch Khng
thy mm bnh Khng thy khun lc Nhi m vo l cy lnh Cy vn
b bnh Viru Giai on no th hin r hot ng sng ca virut? C th nui virut trn mi trng nui cy nhn to nh vi khun c khng? Khng, bt buc phi
nui virut Nghin cu th nghim ca Franken v Conrat (1957) trang 116. Axit nucleic c vai tr quyt V sao virut phn lp c khng phi l virut chng B ? Qua th nghim cho thy thnh phn cu to no ca virut c vai
tr quyt nh? Qua th nghim ta c th kt lun g v c im sng ca virut? - ngoi t bo ch virut biu hin nh th v sinh - Ch trong t bo ch virut mi biu hin nh mt dng sng Vy virut l g? - Virut l mt dng sng v cng n gin, khng c cu to t bo - Chng ch gm hai thnh phn chnh: Li l axit nucleic v V l protein
- Virut sng k sinh bt buc trong t bo vt ch c gi l ht virut hay Virion C nhng tiu chun no phn loi virut? II. PHN LOI VIRUT C th phn loi virut da vo 4 tiu chun sau:c vo loi axit nucleic: Virut - Cn AND hoc Virut ARN - Cn c vo hnh dng: Hnh khi; Hnh tr; Hnh phc hp
- Cn c vo c v hay khng c v: Virut trn hay Virut c v - Cn c vo t bo vt ch: Virut ng vt; virut thc vt hay phage Cng c bi hc Hon thnh phiu hc tp sau bng in vo bng: (+) C (-) Khng Tnh cht C cu to t bo Ch cha AND hoc ARN Cha c AND v ARN
Cha Ribosome Sinh sn c lp Virut Vikhun Tnh cht Virut Vikhun C cu to t bo -
+ Ch cha AND hoc ARN + - Cha c AND v ARN - +
Cha Ribosome - Sinh sn c lp - + + Bi tp v nh Da vo kin thc bi hc v nghin cu ti liu hon thnh bi tp sau
bng in vo bng du (+) C (-) Khng Tnh cht C cu to t bo Ch cha ADN hoc ARN Cha c ADN v ARN Ch cha ARN Ch cha Prtin Cha Ribxm Sinh sn c lp Vi Viru Virit Pri
khu t n n Em bit g v dch cm gia cm? Tnh hnh dch cm gia cm Vit nam c m t bn sau: (Mu biu th vng c dch)
