2018 DSE Biology 生物 討論區

我就係唔明點解答案寫memory cell 係轉左做B/T cell 先，之先B/T cell 先再differentiate 去plasma/killer T cell. 因為一路學都係 memory cell >>plasma /antibodies/Keller T cell. 雖然我知呢樣嘢好minior....

bio啲marking成日變黎變去 好唔一致
正常寫differentiate into plasma cell都應該啱攞到嗰一分

依題背晒成個first and secondary response answer template落去就滿分嫁啦

呢個位佢on9
B cell同T cell各有各的memory cell﹐佢個answer講到好似好似memory cell可以變到T / B cell咁樣

想問下exon同intron洗唔洗學 E4本垃圾書無sosad

唔係有分別架咩？
一隻係antibodies（pathogens: bacterial) ,
一隻係cell-mediated (kill infected cell)咩？

唔洗，書有反而唔正常，唔洗識splicing

我就係唔知錦得唔得。。糾纏左好耐

我地無教到禁詳細啊 即係antibodies 可以tackle bacterial disease —killer T cell 可以kill protist/viral disease (eg malaria)個啲？

見到你個名 杜汶澤把聲就會喺我腦海浮現

antibodies同killer t cells都司以act on bacteria and virus
不過killer T cell係直頭kill the infected cell

明！e家先知

antibodies可以直接bind to bacteria/virus/protozoa去令佢地比人kill by phagocytosis , 亦都可以間接kill infected cells ,只要infected cells表面有antigen , infected cells都係kill by phagocytosis

killer T-cells 其實只可以kill infected cells同cancer cells，就算比佢地見到粒bacteria/virus，佢地都無反應, 唔同antibodies

我地講既infected cells多數係指viral infected cells，virus要有host cell佢先可以replicate

所以antibodies既function可以話係多好多 ,但係humoral immunity需要 helper T-cells去幫手先可以發揮到，因為helper T-cells 幫B-cells去differentiate into plasma cells

睇清楚題目問咩，同埋可以睇我第一頁一樓嘅general reminder，基本上係老生常談，但好多人都做唔到，你問下自己有冇做足

雞 大家都係雞 全部都係雞

因為umbilical cord有bb啲血 同媽媽既genetic make up唔係identical

答案係A？

葉面transpiration左 跟住喺mesophyll cell嗰到係咁扯番啲水 最尾扯到去xylem vessel, creating transpiration pull去喺root到吸水
但其實冇左個root 淨番個xylem同leaf 擺喺兜水入面都有transpiration pull
所以healthy root system唔係necessary