Zitsanzo za Mafunso Okhudza Kapangidwe ka Maselo
Kapangidwe ka maselo ndi nkhani yofunika kwambiri mu sayansi ya maselo, yomwe imafufuza kapangidwe ndi ntchito ya zigawo zosiyanasiyana mkati mwa maselo. M'nkhaniyi, tikambirana zitsanzo zingapo za mavuto okhudzana ndi kapangidwe ka maselo, pamodzi ndi mayankho awo. Izi zikuthandizani kumvetsetsa mfundo zazikulu mu sayansi ya maselo ndi momwe mungawagwiritsire ntchito.
Funso 1: Chiwalo cha Selo
Funso:
Fotokozani ntchito zazikulu za nembanemba ya selo ndi momwe kapangidwe kake kamathandizira ntchito zimenezi.
Kukambirana:
Nembanemba ya selo, kapena nembanemba ya plasma, imagwira ntchito makamaka kuteteza selo ku malo akunja ndikuwongolera kulowa ndi kutuluka kwa mamolekyu kudzera mu selo. Nembanemba iyi imatha kulowa pang'ono, zomwe zimathandiza kusinthana kwa ma ayoni ndi mamolekyu achilengedwe ofunikira kuti selo ligwire ntchito.
Kapangidwe ka nembanemba ya selo makamaka kamakhala ndi phospholipid bilayer yosinthasintha, yokhala ndi mitu ya phosphate yophiphiritsa yomwe imayang'ana kunja ndipo michira ya hydrophobic fatty acid ikuyang'ana mkati. Kapangidwe kameneka kamathandizira ntchito ya nembanemba ya selo mwa:
1. Amapanga malire osinthasintha koma olimba pakati pa mkati ndi kunja kwa selo.
2. Perekani malo omwe amayang'anira kuchuluka kwa mamolekyu kudzera mu mapuloteni a channel ndi carrier omwe ali mu nembanemba.
3. Kuchita ntchito yolumikizirana ndi maselo kudzera m'mapuloteni a receptor pamwamba pa selo.
Kuphatikiza apo, cholesterol yomwe ili mu nembanemba imawonjezera kukhazikika popanda kuchepetsa kusungunuka kwake.
Funso 2: Ma cell Organelles
Funso:
Yerekezerani ndi kusiyanitsa ntchito za mitochondria ndi ma chloroplast m'maselo a eukaryotic.
Kukambirana:
Mitochondria ndi ma chloroplast ndi ma organelle awiri ofunikira m'maselo a eukaryotic omwe amagwira ntchito popanga mphamvu, koma m'njira zosiyanasiyana komanso m'mitundu yosiyanasiyana ya maselo.
Mitochondria:
– Yodziwika kuti ndi “nyumba yamphamvu ya selo.” Ndi komwe kupuma kwa maselo kumachitika, komwe kumasintha shuga ndi mpweya kukhala ATP (adenosine triphosphate), gwero lalikulu la mphamvu la selo.
- Amapezeka pafupifupi m'maselo onse a eukaryotic, nyama ndi zomera.
– Kapangidwe ka mitochondria kali ndi nembanemba iwiri yokhala ndi ma folds amkati otchedwa cristae, omwe amawonjezera malo pamwamba pa maselo kuti azitha kupuma bwino.
Ma chloroplast:
- Amapezeka m'maselo a zomera ndi ma protist ena okha.
– Malo omwe photosynthesis imachitika, njira yomwe imasintha kuwala kwa dzuwa, carbon dioxide, ndi madzi kukhala shuga ndi mpweya.
– Ili ndi kapangidwe kovuta kamene kali ndi nembanemba iwiri komanso milu ya thylakoids yomwe imapanga granum, komwe njira ya photosynthesis imachitikira.
Chomwe ma organelle awiriwa ali nacho n'chakuti onse ali ndi DNA yawoyawo, zomwe zimachirikiza chiphunzitso chakuti zinachokera ku zamoyo za prokaryotic zomwe zinali ndi maselo akale a eukaryotic.
Funso 3: Chitoliro cha Selo
Funso:
Fotokozani ntchito ya nucleus mu maselo a eukaryotic ndi momwe imalamulira ntchito za maselo.
Kukambirana:
Chigawochi chimagwira ntchito ngati malo olamulira maselo a eukaryotic. Nazi zina mwa ntchito zazikulu za chigawochi:
1. Kusunga Chidziwitso cha Majini:
Chiwalochi chimasunga DNA, yomwe ili ndi chidziwitso cha majini cha kukula kwa maselo, kugwira ntchito kwawo, ndi kubereka. DNA imakhala yokhazikika mu mawonekedwe a chromatin, kupatula nthawi yogawa maselo, pamene imagawikana kukhala ma chromosome.
2. Kulemba ndi Kulamulira Majini:
Chigawo chapakati ndi malo olembera, komwe DNA imasinthidwa kukhala messenger RNA (mRNA). Kenako mRNA imasiya chigawocho kuti chisanduke mapuloteni ndi ribosomes mu cytoplasm. Njirayi imawongolera majini omwe amafotokozedwa komanso mpaka pati, mothandizidwa ndi zinthu zolembera ndi kusintha kwa epigenetic.
3. Kubwerezabwereza kwa DNA:
Pakugawikana kwa maselo, nucleus imatsimikizira kuti kubwerezabwereza kwa DNA kumachitika molondola, zomwe zimapangitsa kuti selo lililonse la mwana wamkazi libwerezedwe mofanana.
4. Kuyenda kwa Nucleus-Cytoplasm:
Nembanemba ya nyukiliya ili ndi ma pores a nyukiliya omwe amayang'anira kunyamula kwa mamolekyu monga RNA ndi ma ribosomal subunits pakati pa nyukiliyasi ndi cytoplasm.
Funso 4: Cytoplasm ndi Cytoskeleton
Funso:
Kodi ntchito ya cytoskeleton mu selo ndi yotani, ndipo zigawo zake zimathandizira bwanji ntchito yake?
Kukambirana:
Chigoba cha cytoskeleton ndi netiweki ya ulusi yomwe imapereka kapangidwe ndi chithandizo cha makina a maselo, imasunga mawonekedwe awo, komanso imalola kuyenda kwa organelles ndi mamolekyu mkati mwa selo.
Zigawo zitatu zazikulu za cytoskeleton ndi izi:
1. Ma microtubules:
– Yopangidwa ndi tubulin, imagwira ntchito yosunga mawonekedwe a maselo ndikupereka njira yoyendera kwa ma vesicles ndi organelles kudzera mu ntchito ya mapuloteni oyendetsa magalimoto monga kinesin ndi dynein.
- Zimakhudza kulekanitsa ma chromosomes panthawi ya mitosis.
2. Zingwe za Actin (Zingwe zazing'ono):
- Yopangidwa ndi mapuloteni a actin, imagwira ntchito yoyendetsa maselo kudzera mu pseudopodia, komanso minofu m'maselo a nyama.
- Amagwira ntchito mu kugawa kwa cytoplasmic (cytokinesis) panthawi yogawa maselo.
3. Ma Filamenti Apakati:
- Imagwira ntchito yopatsa maselo kukhazikika kwa kapangidwe kake komanso mphamvu yokoka. Gawoli ndi lokhalitsa kuposa mapangidwe ena a ulusi.
- Imapatsa mphamvu yamakina yomwe imakana kukanda maselo, monga maselo a khungu.
Chigoba cha cytoskeleton chimalola maselo kusintha malinga ndi zosowa zawo, ponse pawiri poyendetsa mkati mwa maselo komanso pochita zinthu ndi chilengedwe chakunja.
Mwa kumvetsetsa ntchito ndi kapangidwe kake ka chilichonse mwa zigawozi, titha kuwona momwe kusinthasintha kwa selo kumathandizira ntchito zosiyanasiyana zamoyo zomwe ndizofunikira pamoyo. Nkhaniyi ikufuna kupereka chithunzi chomveka bwino cha kapangidwe ka maselo ndikuthandizira kumvetsetsa mfundo za sayansi ya maselo.
