Cell

Ƙwayar halitta (cell) wani abu ne ko kuma tushe da ginshikin asalin halitta ko tubalin samuwar duk wani abu da ke da rai. Nazarin ƙwayar halitta tun daga ainihin ginshikinta da tsarinta zuwa kan ayyukan kowace ƙwayar halitta guda ɗaya ana kiran shi ilimin halittu (Cell Biology). Robert Hooke shi ne masanin ƙwayoyin halittu na farko wanda ya gano cell.

Dukkan halittu sun kasance daga asalin tushen ƙwayar halitta ne wato cell. Ko dai su kasance daga ƙwayar halitta ɗaya (wato unicellular), ko kuma ƙwayoyin halitta da yawa (multicellular). Mycoplasmas kuma su ne mafi ƙanƙantar ƙwayoyin halitta da aka sani. Ƙwayoyin halitta su ne tubalan ginin duk wani abu mai rai. Suna samar da tsari ga jiki kuma suna canja abubuwan gina jiki da aka ci daga abinci zuwa sinadarai. Ƙwayoyin halitta suna da rikitarwa kuma sassansu suna yin ayyuka daban-daban a jikin halittu. Suna da siffofi da girma dabam-dabam, suna kama da tubalin gine-gine. Jikin ɗan’adam ya ƙunshi ƙwayoyin halitta masu siffofi da girma dabam-dabam.

Kwayoyin su ne mafi ƙanƙanta a matakan samar da halitta a kowace sigar abubuwa masu rai da rayuwa. Daga nau’in halitta zuwa wata nau’in halittar, adadin ƙwayoyin halitta na iya bambanta. Mutane suna da ƙarin adadin ƙwayoyin halitta idan aka kwatanta da na ƙwayoyin bakteriya.

Kwayoyin halitta sun ƙunshi ƙwayoyin cells da yawa waɗanda ke yin ayyuka na musamman don gudanar da rayuwa. Dukkan gaɓoɓin jiki suna da tabbatattun tsarin ƙwayoyin halittarsu. Haka zalika abubuwan da ake yin gadon su, su ma suna cikin ƙwayoyin halitta (cells).

Gano ƙwayoyin halitta

Gano ƙwayoyin halitta na daga cikin muhimman ci gaba a fagen kimiyya. Yana taimakawa a fahimci cewa dukkanin ƙwayoyin halitta sun ƙunshi ƙwayar cell ne, kuma waɗannan ƙwayoyin suna taimakawa wajen gudanar da matakai daban-daban na rayuwa. Tsari da ayyukan kwayoyin halitta sun taimaka wajen fahimtar rayuwa da hanyoyi masu sauƙi da inganci.

Robert Hooke ya gano ƙwayar halitta ne a shekara ta 1665. Robert Hooke ya lura da wasu tarin kwalabe a ƙarƙashin na’urar microscope, kuma ya lura da ƙananan gine-gine waɗanda suka tuna masa da wasu ƙananan ɗakuna. Saboda haka, ya sanya wa waɗannan ɗakuna suna a matsayin ƙwayar halitta (cell). Sai dai kuma microscope ɗinsa yana da ƙayyadadden aikin da zai iya yi, don haka, ba zai iya ganin komai a cikin tsarin aikinsa ba. Dalilin wannan iyakancewa, Hooke ya tabbatar da cewa waɗannan halittun marasa rai ne.

Daga baya Anton Van Leeuwenhoek ya lura da ƙwayar halitta a ƙarƙashin wani microscope mai ƙarin girman fasaha. A wannan lokacin, ya lura cewa ƙwayoyin cells sun nuna wani nau’i na motsi (motility). Sakamakon haka, Leeuwenhoek ya yanke cewa waɗannan ƙananan halittun suna da rai. A ƙarshe, bayan wasu nazarce-nazarce da yawa da suka gudana, waɗannan ƙwayoyin halitta an ba su sunayen ƙwayoyin halittar dabbobi.

A cikin shekara ta 1883, Robert Brown, ɗan asalin ƙasar Scotland, ya ba da ƙarin haske na farko game da tsarin kwayoyin halitta. Ya yi kokarin kwatanta tsakiyar ƙwayar halittar orchids.

Siffofin kwayoyin halitta

Wadannan su ne nau’ikan mahimman siffofin kwayoyin halitta (cells) kamar yadda suka zo a kafar U Unacademy:

• Kwayoyin halitta suna samar da tsarin siffa da garkuwa ga jikin halitta.
• An tsara sashen cikin ƙwayar halitta zuwa gaɓoɓin jikin mutum daban-daban da ke kewaye da kuma wani tantani membrane daban.
• Nucleus (wato babban organelle) yana riƙe da bayanan ƙwayoyin halitta na dole don haihuwa da kuma girman ƙwayar halitta.
• Kowace ƙwayar halitta tana da tsakiya guda ɗaya da ƙwayoyin da ke ɗaure da membrane a cikin cytoplasm.
• Mitochondria, ƙwayar halitta mai ɗaure membrane biyu ita ce ke da alhakin aikin makamashi mai mahimmanci don rayuwar ƙwayar halitta.
• Lysosomes na narkar da kayan da ba a so a cikin ƙwayar halitta.
• Endoplasmic reticulum yana taka muhimmiyar rawa a tsarin cikin ƙwayar halitta ta hanyar haɗa ƙwayoyi halitta zaɓaɓɓu da sarrafa su  da rarraba su zuwa wuraren da suka dace.

Ire-iren kwayoyin halitta

Ƙwayoyin halitta suna kama da masana’antu tare da ma’aikata daban-daban da sassan da ke aiki zuwa ga manufa ɗaya. Nau’o’in ƙwayoyin halitta daban-daban suna yin ayyuka daban-daban, akwai nau’ikan ƙwayar guda biyu, a cewar Byju’s. (2022):

• Prokaryotes
• Eukaryotes

• Ƙwayoyin halitta nau’in prokaryotic

Kwayoyin prokaryotic ba su da tsakiya. Maimakon haka, wasu prokaryotes kamar ƙwayoyin bakteriya suna da yanki a cikin ƙwayar halitta inda ake dakatar da ƙwayoyin halittar gado. Ana kiran wannan yanki da suna nucleoid.

Dukkansu kwayoyin halitta ne masu guda ɗaya. Misalai sun haɗa da archaea, bakteriya, da cyanobacteria. Girman ƙwayar halitta yana daga 0.1 zuwa 0.5 µm a tsarin awon diamita. Abubuwan gado na iya zama DNA ko RNA.

Prokaryotes cells gabaɗaya suna haihuwa ta hanyar fission na binary, wani nau’i ne na haihuwa ta hanyar yin jima’i. Haka nan suna amfani da tsarin haɗin gwiwa, wanda yawanci ana ganin su a matsayin prokaryotic daidai da haihuwa ta jima’i, amma ba haihuwar jima’i ba ce.

• Kwayoyin halitta nau’in eukaryotic

Kwayoyin eukaryotic suna siffanta da ainihin tsakiyar ƙwayar halitta. Girman ƙwayar halittar (cell) yana tsakanin 10-100 µm a bisa tsarin ma’aunin diamita. Wannan babban nau’in ya ƙunshi halittu kamar shuke-shuke, fungi, protozoans, da dabbobi.

Membran plasma na da alhakin lura da jigilar abubuwan gina jiki da electrolytes a ciki da wajen ƙwayar. Haka nan yana da alhakin sadarwa tsakanin ƙwayar halitta zuwa ƙwayar halitta. Suna da tsarin haihuwa ta hanyar jima’i da kuma haihuwa ba ta hanyar jima’i ba.

Akwai wasu siffofi masu banbanci tsakanin ƙwayoyin halittar tsirrai da ƙwayoyin halittar dabbobi. Misali, ƙwayar halittar tsirrai ta ƙunshi chloroplast, central vacuoles, da sauran plastids, yayin da ƙwayoyin halittar dabbobi ba su da ita.

Banbanci tsakanin prokaryotic da eukaryotic cells

Prokaryotic cells	Eukaryotic cells
1. Suna da tsarin unicellular	1. Ko dai unicellular ko multi-cellular
2. Suna da cell wall	2. Akan samu cell wall ko a rasa
3. Ba su da nucleus	3. Akwai nucleus kodayaushe
4. Akwai DNA a tsarin circular.	4. Akwai DNA a tsarin linear.
5. Ba su da mitochondria	5. Akwai mitochondria koyaushe

Tsarin kwayoyin halitta

Tsarin ƙwayar halitta ya ƙunshi sassa ɗaya tare da tabbatattun ayyuka masu mahimmanci don gudanar da ayyukan rayuwa. Waɗannan abubuwan sun haɗa cell wall, cell membrane, cytoplasm, nucleus, da cell organelles, a yadda Admin. (2022) ya zayyana a shafin BUJUS

• Cell membrane

Tantanin ƙwayar halitta na tallafawa da kare ƙwayoyin halitta. Yana sarrafa motsin abubuwa a ciki da wajen ƙwayar halitta. Yana raba tantanin ƙwayar halitta daga yanayin waje. Tantanin ƙwayar halitta yana cikin dukkan ƙwayoyin halitta (cells).

Tantanin ƙwayar halitta shi ne murfin waje na ƙwayar halitta wanda duk wasu gabobin jiki, kamar cytoplasm da nucleus, ke rufe da shi. Haka nan ana kiran shi da membrane plasma.

Ta hanyar tsari, tantani ne mai porous, wanda ke ba da izinin motsin abubuwa masu zaɓi a ciki da wajen ƙwayar halitta. Bayan wannan, ƙwayar tantanin halitta tana kare sashin ƙwayar halitta daga lalacewa da zubewa. Yana samar da tsari irin na bango tsakanin ƙwayar halitta guda biyu da kuma tsakanin tantanin halitta ƙwayar da kewaye.

Tsire-tsire da shuke-shuke ba sa motsi, don haka tsarin tantanin halittarsu ya dace sosai don kare su daga abubuwan waje. Bangon tantanin halittarsu  yana taimakawa wajen ƙarfafa aikinsu.

Cell wall

Cell wall, (wato katangar ƙwayar halitta) ita ce mafi shaharar ɓangaren tsarin ƙwayar halitta. Ta ƙunshi cellulose, hemicellulose da pectin. Katangar ƙwayar halitta tana nan ta musamman a cikin ƙwayoyin halittar shuke-shuke. Tana kare membrane plasma da sauran sassan ƙwayar halitta. Katangar tantanin halitta ita ce mafi girman saman ƙwayar halittar shuka.

Katangar ƙwayar halitta tana da tsari mai tsauri da kauri da ke kewaye da ƙwayar halitta. Tana ba da tsari da kariya ga ƙwayoyin halitta kuma tana kare su daga jijjiga da raunuka.

Cytoplasm

Cytoplasm wani abu ne mai kauri, bayyananne, mai kama da jelly wanda ke cikin membrane na tantanin halitta. Yawancin siffofin sinadarai a cikin ƙwayar halitta suna faruwa a cikin wannan cytoplasm. Ƙwayoyin halitta irin su endoplasmic reticulum, vacuoles, mitochondria, ribosomes, ana dakatar da su a cikin wannan cytoplasm.

Nucleus

Tsakiyar ƙwayar halitta ta ƙunshi abubuwan da ake yin gado na ƙwayar halitta, DNA. Yana aika saƙo zuwa ƙwayar halitta don girma da bunƙasa da rarrabuwa da kuma mutuwa. An kewaye nucleus da wani nau’in ambulan wanda ke ware DNA daga sauran kwayoyin halitta. Tsakiyar ƙwayar halitta tana kare DNA, kuma shi ne ɓangarorin tsarin ƙwayar halitta.

Cell organelles

Kwayoyin halitta sun ƙunshi nau’ikan ƙwayoyin halitta daban-daban waɗanda ke yin wasu ayyuka na musamman don gudanar da ayyukan rayuwa. Mabambantan gabobin tantanin halitta suna da manyan ayyuka kamar haka:

Nucleolus

Nucleolus shi ne wurin haɗin ribosome. Har ila yau, yana shiga cikin sarrafa ayyukan kwayoyin da haihuwarsu.

Nuclear membrane

Nuclear membrane yana kare tsakiyar ƙwayar halitta ta hanyar samar da iyaka tsakanin tsakiyar da sauran ƙwayoyin halitta.

Chromosomes

Chromosomes suna taka muhimmiyar rawa wajen tantance jinsin mutum. Kowace ƙwayar halittar ɗan’adam ta ƙunshi nau’i-nau’i har guda 23 na chromosomes.

Endoplasmic reticulum

Endoplasmic reticulum na aikin jigilar abubuwa a cikin ƙwayar halitta. Yana taka muhimmiyar rawa a cikin tsarin metabolism na carbohydrates, kira na lipids, steroids da sinadarai.

Golgi bodies

Golgi bodies ana kiran su cell’s post office, yayin da suke aikin jigilar kayayyaki a cikin ƙwayar halitta.

Ribosome

Ribosomes su ne masu aikin haɗa sinadarin furotin na ƙwayar halitta.

Mitochondria

Mitochondion ana kiransa the power house of the cell.” Ana kiran shi da haka saboda yana samar da ATP – wato makamashin kuzarin ƙwayar halitta.

Lysosomes

Lysosomes suna kare ƙwayoyin halitta ta hanyar mamaye jikin baƙin halittun da ke shiga cikin ƙwayoyin halitta kuma suna taimakawa wajen sabunta ƙwayoyin halittar.

Chloroplast

Chloroplasts su ne ƙwayoyin halitta na farko don gudanar photosynthesis ga shuke-shuke. Sun ƙunshi pigment da ake kira chlorophyll.

Vacuoles

Vacuoles suna adana abinci da ruwa da sauran sinadarai a cikin ƙwayar halitta.

Ayyukan ƙwayar halitta

Kwayoyin halitta suna yin manyan ayyuka masu mahimmanci don ingantawa da haɓaka tsarin halittu. Muhimman ayyukan kwayoyin halitta su ne kamar haka a cewar shafin Libretexts. (2021):

Provides support and structure

Duk kwayoyin halitta sun kasance daga cell. Su ne tushen tsarin dukkan halittu. Katangar ƙwayar halitta da cell membrane su ne manyan abubuwan da ke aiki don ba da garkuwa da tsari ga kwayoyin halitta. Misali, fatar jiki tana ƙunshe da adadi mai yawa na cells. Xylem da ke cikin shuke-shuke na jijiyoyi an yi shi ne da cells waɗanda ke ba da garkuwa da tsari ga tsire-tsire da shuke-shuke.

Facilitate growth mitosis

A cikin tsarin mitosis, babban ƙwayar halitta tana rabuwa zuwa ƙananu. Don haka, cell suna haɓaka kuma suna sauƙaƙe girma a cikin ƙwayoyin halitta.

Allows transport of substances

Sinadarai iri-iri ne ƙwayar halitta ke shigo da su don aiwatar da aikin sinadarai da ke gudana a cikin ƙwayar halittar. Gurɓatattun abubuwa da aka samar ta hanyar sinadarai ana kawar da su daga cikin ƙwayar halitta ta hanyar jigilar aiki da motsi. Ƙananan kwayoyin sinadarai irin su oxygen, carbon dioxide, da ethanol suna yaɗuwa a cikin membrane. Manya-manyan ƙwayoyin bakteriya suna yaɗuwa a cikin membrane ta hanyar sufuri inda ƙwayar halitta as ke buƙatar kuzari mai yawa don jigilar abubuwan.

Energy production

Kwayoyin suna buƙatar makamashi don aiwatar da matakai daban-daban na sinadarai. Kwayoyin suna samar da wannan makamashi ne ta hanyar da ake kira photosynthesis a cikin tsirrai da numfashi a cikin dabbobi.

Aids reproduction

Ƙwayar halitta tana taimakawa wajen haihuwa ta hanyoyin da ake kira mitosis da meiosis. Ana kiran Mitosis a matsayin haihuwa ta hanyar asexual inda ƙwayar halitta iyaye ke rarrabuwa don samar da ƙwayoyin halittar ‘ya’ya. Meiosis yana sa ‘ya’yan kwayoyin halitta su kasance daban-daban daga kwayoyin halitta.

Don haka, za a iya fahimtar dalilin da yasa aka san cell a matsayin ginshiki da tushen rayuwa. Wannan shi ne saboda suna da alhakin samar da tsari ga ƙwayoyin halitta kuma suna yin ayyuka da yawa da suka wajaba don aiwatar da hanyoyin rayuwa.

Manazarta

Admin. (2022a, July 5). What is a cell? – Definition, structure, types, functions. BYJUS. 

Byju’s. (2022, July 4). What are the 2 main types of cells- What Is the main difference between the 2 types. BYJUS

Libretexts. (2021, March 6). 5: Structure and function of plasma membranes. Biology LibreTexts.