Chitsanzo cha Mafunso Okambirana pa Ma polima Achilengedwe
Ma polima achilengedwe ndi zinthu zachilengedwe zomwe zimapezeka mwachilengedwe zomwe zimakhala ndi mamolekyu akuluakulu opangidwa kuchokera ku mayunitsi ang'onoang'ono otchedwa ma monomers. Ma polima awa amagwira ntchito yofunika kwambiri pa moyo watsiku ndi tsiku ndipo amagwiritsidwa ntchito kwambiri m'magawo osiyanasiyana a mafakitale, mankhwala, ndi zamankhwala. Zitsanzo zodziwika bwino za ma polima achilengedwe ndi monga cellulose, mapuloteni, rabara wachilengedwe, ndi ma nucleic acid. Pansipa, tikambirana zitsanzo zingapo za mavuto okhudzana ndi ma polima achilengedwe omwe angathandize kumvetsetsa bwino nkhaniyi.
Funso 1: Kapangidwe ndi Ntchito ya Ma polima Achilengedwe
Funso:
Selulosi ndi mapuloteni ndi mitundu iwiri yosiyana ya ma polima achilengedwe. Fotokozani kusiyana kwa kapangidwe ka maselolulosi ndi mapuloteni ndi ntchito zawo m'zamoyo.
Kukambirana:
Kapangidwe:
Cellulose ndi polima ya chakudya chopangidwa ndi ma monomers a glucose. Glucose yomwe ili mu cellulose imalumikizidwa pamodzi ndi ma bond a 1,4-β-glycosidic. Kapangidwe ka cellulose ndi kolunjika ndipo ma bond a haidrojeni pakati pa unyolo wa glucose amaupangitsa kukhala wolimba kwambiri komanso wosagonja kuwonongeka.
Kumbali inayi, mapuloteni ndi ma polima a amino acid opangidwa ndi maunyolo ataliatali a amino acid olumikizidwa ndi ma peptide bonds. Kapangidwe ka mapuloteni kamagawidwa m'magawo angapo: primary (linear makonzedwe a amino acid), secondary (α-helical kapena β-sheet structure yomwe imayambitsidwa ndi ma hydrogen bonds), tertiary (kupindika kovuta kwambiri komwe kumakhudzidwa ndi kuyanjana pakati pa ma amino acid side chains), ndi quaternary (maunyolo pakati pa ma polypeptide chains angapo).
Ntchito:
Cellulose ndi gawo lalikulu la kapangidwe ka makoma a maselo a zomera. Imapereka mphamvu ndi kusinthasintha, imathandiza zomera kukhala zowongoka, komanso imateteza maselo ku kuwonongeka kwa makina. Cellulose imagwiritsidwanso ntchito ngati zinthu zopangira m'mafakitale monga mapepala, nsalu, ndi mapulasitiki osinthika.
Mapuloteni ali ndi ntchito zosiyanasiyana m'zamoyo, kuphatikizapo ma enzyme omwe amafulumizitsa zochita za mankhwala, monga zigawo za kapangidwe kake (monga collagen pakhungu ndi minofu yolumikizana), monga mahomoni omwe amawongolera ntchito zosiyanasiyana za thupi, monga ma antibodies omwe amalimbana ndi matenda, komanso monga mapuloteni onyamula omwe amasuntha mamolekyu ena kudutsa nembanemba ya selo.
Funso 2: Kapangidwe ka Thupi ndi Mankhwala a Ma polima Achilengedwe
Funso:
Kambiranani za mphamvu ndi mphamvu za mphira wachilengedwe ndipo fotokozani momwe kuphulika kwa phulusa kungakhudzire mphamvu zimenezi.
Kukambirana:
Rabala yachilengedwe (kapena latex) ndi polima yachilengedwe yomwe gawo lake lalikulu ndi polyisoprene. Kapangidwe kake kapadera ka mphira yachilengedwe ndi kusinthasintha kwake, komwe kumalola kuti ibwerere ku mawonekedwe ake oyambirira itatambasulidwa kapena kukakamizidwa. Komabe, mphira yachilengedwe yosaphika ili ndi vuto la kukhala yotetezeka ku kutentha kwambiri, kukhuthala, ndi kusweka.
Mankhwala a mphira wachilengedwe ndi monga kusungunuka mu zinthu zosungunulira zachilengedwe zomwe sizili polar komanso kukhudzidwa ndi okosijeni ndi kuwonongeka kwa kutentha. Kapangidwe kake kolunjika, kosakhala kolumikizana ndi netiweki kamalola mamolekyu kuti azidutsana, zomwe zimapangitsa mphira wachilengedwe kukhala womata kutentha kwambiri komanso wosweka kutentha kochepa.
Kutulutsa mpweya woipa (Vulcanization) ndi njira ya mankhwala yomwe imagwiritsidwa ntchito kukonza mphamvu za makina a mphira wachilengedwe mwa kupanga maulalo pakati pa unyolo wa polima kudzera mu kutentha ndi sulfure. Njirayi imawonjezera kukana kusintha kwa kutentha, imapereka kukhazikika kwa kutentha, komanso kukana kuyamwa kwa madzi ndi mankhwala. Kutulutsa mpweya woipa (Vulcanization) kumachepetsanso kumamatira kwa mphira wachilengedwe pa kutentha kwambiri ndikuwonjezera mphamvu yake, zomwe zimapangitsa mphira woipa kukhala wolimba komanso wosamva kupweteka.
Funso 3: Kupanga kwa Ma polima Achilengedwe
Funso:
Kodi kupanga mapuloteni kumachitika bwanji m'maselo ndipo kodi ntchito ya RNA ndi yotani pankhaniyi?
Kukambirana:
Njira yopangira mapuloteni m'maselo imatchedwa kumasulira, komwe ndi gawo lomaliza la majini. Njirayi imachitika mu ribosomes, ma organelles omwe amachititsa kupanga mapuloteni, ndipo imaphatikizapo mitundu ingapo ya RNA: mRNA (messenger RNA), tRNA (transfer RNA), ndi rRNA (ribosomal RNA).
1. Kulemba:
Njira yopangira mapuloteni imayamba ndi kulemba, komwe gawo la DNA lomwe limalemba jini la puloteni inayake limakopedwa kukhala mRNA. Njirayi imachitika mu nyukiliyasi ya selo, ndipo mRNA yomwe imachokera imapita ku cytoplasm.
2. Kumasulira:
MRNA ikalowa mu cytoplasm, imagwirizana ndi ma ribosome. Ribosome imayenda motsatira chingwe cha mRNA, ndipo ma tRNA amanyamula ma amino acid ofanana ndi ma codon a mRNA kupita ku ma ribosome. TRNA iliyonse imakhala ndi anticodon yomwe imalumikizana ndi codon yofanana pa mRNA, kuonetsetsa kuti amino acid yolondola yawonjezedwa ku unyolo wa polypeptide womwe ukukula.
3. Kuyambitsa:
Njira yosinthira imayamba ndi kuyambitsa, pamene ribosome imazindikira codon yoyambira (AUG) pa mRNA. TRNA yoyambitsa imanyamula methionine, amino acid yoyamba mu unyolo wa polypeptide.
4. Kutalikitsa:
Kenako, njira yotalikira imawonjezera ma amino acid imodzi ndi imodzi ku unyolo wa polypeptide. TRNA yomwe imanyamula amino acid yotsatira imalowa mu malo a A a ribosome, ndipo peptide bond imapangidwa pakati pa amino acid mu malo a A ndi amino acid pa unyolo wa polypeptide womwe ukukula.
5. Kutha kwa ntchito:
Njira yomasulira imatha ndi kutha pamene ribosome ifika pa codon yoyima (UAA, UAG, kapena UGA) pa mRNA. Codon iyi siilemba amino acid iliyonse, koma imayambitsa kutulutsidwa kwa unyolo wa polypeptide womalizidwa kuchokera ku ribosome.
Mu ndondomeko yonseyi, mRNA imagwira ntchito ngati pulani ya mndandanda wa amino acid m'mapuloteni, tRNA imanyamula ma amino acid oyenera kutengera mndandanda wa codon, ndipo rRNA imapanga gawo logwira ntchito la ribosome, zomwe zimapangitsa kuti ma peptide bonds apangidwe. Njirayi imayendetsedwa bwino kwambiri ndipo imaonetsetsa kuti mapuloteni omwe amachokera akugwirizana ndi jini yomwe ili mu DNA.
Funso 4: Ma polima achilengedwe m'moyo watsiku ndi tsiku
Funso:
Perekani zitsanzo zitatu za momwe ma polima achilengedwe amagwiritsidwira ntchito m'moyo watsiku ndi tsiku ndipo fotokozani ubwino wawo poyerekeza ndi ma polima opangidwa.
Kukambirana:
1. Cellulose mu Pepala ndi Nsalu:
Cellulose imagwiritsidwa ntchito kwambiri mumakampani opanga mapepala ngati chinthu chachikulu chopangira zinthu zopangira. Mumakampani opanga nsalu, cellulose ndi maziko opangira ulusi wachilengedwe monga thonje. Ubwino wa cellulose kuposa ma polima opangidwa ndi zinthu zopangira ndi kukhalitsa kwake komanso kuwonongeka kwachilengedwe. Cellulose imatha kuwola mwachilengedwe popanda kuipitsa chilengedwe, mosiyana ndi ma polima ambiri opangidwa, omwe amatenga zaka makumi ambiri mpaka mazana ambiri kuti awonongeke.
2. Mphira Wachilengedwe M'matayala a Magalimoto:
Rabala yachilengedwe imagwiritsidwa ntchito popanga matayala a galimoto chifukwa cha kusinthasintha kwake komanso kukana kutopa. Ubwino wa rabala yachilengedwe kuposa rabala yopangidwa ndi zinthu ndi monga kukhazikika kwa kutentha kwake komanso kuthekera kwake kubwerera ku mawonekedwe ake oyambirira atagwiritsidwa ntchito movutikira. Ngakhale kuti rabala yopangidwa ndi zinthu ilinso ndi ntchito zosiyanasiyana, rabala yachilengedwe imagwirabe ntchito chifukwa cha magwiridwe ake abwino kwambiri nthawi zina.
3. Mapuloteni mu Zakudya ndi Mankhwala:
Mapuloteni monga albumin ndi gelatin amagwiritsidwa ntchito m'mafakitale azakudya ndi mankhwala. Albumin ingagwiritsidwe ntchito ngati chokhazikika mu zakudya, pomwe gelatin imagwiritsidwa ntchito mu makapisozi ndi zowonjezera mankhwala. Ubwino wa mapuloteni achilengedwe awa ndikugwirizana kwawo ndi thupi komanso kuthekera kwawo kugayidwa ndikukonzedwa ndi thupi, mosiyana ndi ma polima ena opangidwa, omwe angayambitse zotsatirapo zoyipa kapena zotsatirapo zoyipa.
Ma polima achilengedwe amapereka ubwino waukulu pakugwirizana ndi chilengedwe komanso kukhazikika, kuchepetsa kudalira mankhwala omwe angawononge ndikuwononga zachilengedwe. Kugwiritsa ntchito ndi kupanga ma polima achilengedwe kumathandiziranso chuma chosamalira chilengedwe komanso chokhazikika pa zinthu zobwezerezedwanso.
Mapeto
Ma polima achilengedwe ndi zinthu zofunika kwambiri pa moyo ndi ukadaulo. Mwa kumvetsetsa makhalidwe awo, kapangidwe kake, kapangidwe kake ka zinthu, ndi momwe amagwiritsidwira ntchito, titha kufufuza mozama ubwino ndi momwe ma polima achilengedwe angagwiritsidwire ntchito m'magawo osiyanasiyana. Kuchita nawo maphunziro kudzera muzochita zolimbitsa thupi, monga zomwe takambirana pamwambapa, kungatithandize kumvetsetsa bwino komanso kugwiritsa ntchito ma polima achilengedwe m'miyoyo yathu ya tsiku ndi tsiku.
