Cell nkewa: nkọwa nke ihe ndị bụ isi Filiks

Cell nkewa - ọ bụ a eke usoro na-enye ohere maka nkịtị ibu, mmepe na mmeputakwa nke organism. Nke a enwekwu ọnụ ọgụgụ nke mkpụrụ ndụ na-ebu anụ ahụ ibu, mmekọahụ amụba na nnyefe nke butere n'aka ihe. The isi ụdị nke cell nkewa - a meiosis na mitosis. Onye ọ bụla n'ime ndị a Filiks nwere ụfọdụ peculiarities.

mitosis

Mitosis - a cell nkewa, emecha si nne nwa mkpụrụ ndụ nke na-kpụrụ abụọ nwa chromosomes na yiri nọmba iji. Ndị dị otú ahụ Filiks mgbe niile emee na somatic mkpụrụ ndụ nke ihe organism, na-enye ibu, mmepe na imu nke anụ ahụ na akụkụ.

The ndụ okirikiri nke mkpụrụ ndụ nwere ike kere n'ime interphase na mitosis. Interphase - ya mere a na-akpọ udo ogbo, n'oge nke e nwere n'ọrụ njikọ na ìgwè bekee mkpa maka cell nkewa. N'ebe mmalite nke mitosis emee ibawanye nọmba nke chromosomes.

Mitosis na-emekarị kewara n'ime anọ isi nkebi.

• Prophase. N'oge a ị ga-achọpụta na mmalite nke chromosome odide. Abụọ yiri chromosomes na-interconnected otu centromere. Na mbu e nwere a nkewa prophase na centrioles. Ugbu a abụọ nwa centrioles amalite nwayọọ nwayọọ achụsakwa abụọ abụghị n'akụkụ nke cell. Otú ọ dị, ha ịnọgide na-agbụ mkpa protein filaments - mere kpụrụ nkewa spindle. Site na njedebe nke a na ogbo, ndị chromosomes ebelata ma na-ukwuu thicker ma gaa ụwa nke cell.
• Metaphase - nnọọ obere ogbo, nke-amalite na itinye n'ọnọdụ nke chromosomes na ụwa nke cell. Around n'otu oge ahụ, n'otu oge nile chromosomes bụ nkewa nke centromere.
• Anaphase - eri spindle n'ịnyịnya na centromere nke chromosome. Mgbe oge a nwa chromosome a nwayọọ nwayọọ na-akpụ akpụ ndị na-abụghị okporo osisi ya. Ọ na-kweere na eri spindle bụghị nanị eduzi chromosomes, kamakwa n'ihi ọnụnọ nke ATP na-ebelata, ngwa ngwa ha divergence.
• Telophase - amalite mgbe oge mgbe chromosomes gara okporo osisi ya. Ha tụsaratụ ma na-anaghị achọpụta --alọta na-ezu ike ala. Around ụyọkọ nke chromatin bụ a njikọ nke a ọhụrụ nuclear envelopu. Ke ukem na cell nkewa emee - cytoplasm na organelles kewara dokwara n'etiti nwa formations.

meiosis

Meiosis - usoro a nke cell nkewa, n'oge nke anọ gametes kpụrụ na a otu set of chromosomes. Ndị dị otú ahụ Filiks na-ewere ọnọdụ n'oge guzobe nke gametes - spermatozoids, ovules (osisi nke mere na e guzobere spores). Ndị dị otú ahụ Filiks-enye maka mgbanwe nke mkpụrụ ndụ ihe nketa na ihe onwunwe na combinatorial mgbanwe. Mgbe abụọ gametes, ọ bụla nke nwere nanị ọkara nke mkpụrụ ndụ ihe nketa na ihe onwunwe, ọnụ ọgụgụ nke chromosomes na-ebelata, ma ha usoro ihe gbanwere.

The usoro nke na-akpụ gametes mejupụtara abụọ obere meiotic nkewa, na onye ọ bụla nke niile dị n'elu nzọụkwụ nwere ike oké. Ma n'etiti ìgwè abụọ nke interphase na-adịghị kwuru na, na DNA njikọ emee. N'ihi ya, nke abụọ abatakwa prophase nke abụọ mkpụrụ ndụ na a otu set of chromosomes (na ụmụ mmadụ bụ 46). N'ihi n'ìgwè nke abụọ - a 4 gametes nke nwere 23 chromosomes.

amitosis

Amitosis - bụ uncharacteristic cell nkewa, nke pụtara adịkarịghị. Mgbe a cell retains niile n'ahụ ọrụ. N'oge usoro a, e nweghị mbiputegharị nke mkpụrụ ndụ ihe nketa na ihe onwunwe na cell nkewa. Divisible naanị kernel, ma na-enweghị na-akpụ a mitotic spindle. Dị ka a N'ihi nke a usoro, chromosomes dị iche na random iji - kpụrụ multi-nucleate cell. Ọ ga-kwuru na amitosis-emekarị ịka nká na ma ọ bụ na-anwụ anwụ na mkpụrụ ndụ, ma ọ bụ na pathologically gbanwere agbanwe owuwu (neoplastic mkpụrụ ndụ).