Qhov twg phev yog tsim: yuav ua li cas thiab nyob qhov twg kev kawm ntawv

Txiv neej yuav tsum tsis mas tshaj cov poj niam. Yog li ntawd, ib txhia ntawm lawv yog cov heev xav nyob rau hauv lub ntaus ntawv tus kheej lub cev, thiab tshwj xeeb tshaj yog nws cov tseem ceeb tshaj plaws hauv nruab nrog cev. Bold nyob rau hauv cov ntaub ntawv no yog cov kws kho mob, thiab tus so cia li rau kev nyeem ntawv yuav tsum tau ntaub ntawv. Qhov tseem ceeb tshaj cov lus nug yog: qhov twg phev yog tsim? Yuav ua li cas puas tau nws zoo li cas? Yuav ua li cas ntau lub neej? Yuav ua li cas mus? Wb sim teb lawv nyob rau hauv xws li ib txoj hais tias nws yog ib qhov tseeb rau txhua leej txhua tus.

txhais

Ua ntej teb cov lus nug, qhov twg yog tsim phev, ib tug yuav tsum to taub hais tias nws sawv cev rau. Phev - qhov no kab hlwb ntawm cov tsiaj thiab tib neeg. Feem ntau, cov hlwb yuav tau tsiv mus nyob nquag, uas yog tseem ceeb heev nyob rau hauv kev txiav txim mus cuag cov qe thiab fertilize nws.

Raws li tus piv rau tus poj niam tus kab hlwb, phev hlwb yog me me, nimble, thiab nyob rau tib lub sij hawm nyob rau hauv lub cev zus ib tug loj tus naj npawb (li opposed mus rau lub qe, uas ib tug yog lub crown ntawm peb caug poj niam endocrine system).

Tus qauv ntawm no kab cell ntawd hais tias tag nrho cov tsiaj thiab fungi muaj ib qho txwv zeej txwv koob - ib zaug xwb-celled kab mob. Feeb, tej txiv neej nrog txiv neej pw lub hlwb, txawm nyob rau hauv cov nroj tsuag, hu ua cov phev, txawm hais tias muaj feem xyuam rau lawv thiab lub ntsiab txhais ntawm "phev" thiab anterozoidy.

Phev hlwb nyob rau hauv cov tsiaj

Oddly txaus, tab sis cov tsiaj yog tsis ntau sib txawv ntawm ib tug neeg nyob rau hauv cov nqe lus nug ntawm cov qauv thiab cov kev ua ntawm tus kab hlwb. Qhov twg phev raug tsim? Yuav ua li cas lawv saib? Puas muaj tej yam tseem ceeb cov kev hloov?

Tej tsiaj phev muaj ib lub taub hau, ib nrab feem thiab tus Tsov tus tw (los yog flagellum). Lub taub hau, feeb, yog lub noob pob kws, uas yog ib nrab ntawm cov xov tooj ntawm chromosomes. Nyob rau hauv tas li ntawd mus rau lub caj ntaub ntawv nyob rau hauv lub taub hau muaj enzymes rau cov kev taw qhia ntawm cov qe thiab cov centriole. Lub intermediate ib feem yog tib yam caj dab, muaj yog ib tug loj mitochondrion, uas muab lub zog thiab koom tes rau nws cov flagellum zog.

Tshwj los ntawm cov qauv uas muaj los ntawm saum toj no tej hom ntawm thoob dej yug ntses ntses uas nws cov phev muaj ob flagella. Raws li nws hais txog crustaceans (tej zaum lawv yuav ua tau peb los yog ntau tshaj "tails" los ntawm tus kab hlwb). Tab sis roundworms evolution tu siab los ntawm me me hlwb - yog tsis muaj cilia los yog flagella nyob ib ncig ntawm nws lub cev. Pw ua ke hlwb ntawm cov tsiaj muaj ib lub hnab yas cell phab ntsa uas tso cai rau koj mus next siv prolegs. Nyob rau hauv newts rau phev tam sim no tis ntses. Tab sis muaj variations tsis tau tsuas yog nyob rau hauv lub tails, tab sis kuj nyob rau hauv lub taub hau. Yog hais tias ib tug neeg uas lawv ellipsopodobnye, nws yog nas thiab nas yuav khav kryukopodobnoy daim ntawv.

Lub qhov ntev ntawm lub tsev me nyuam hlwb nyob rau hauv cov txiv neej yog heev me me - los ntawm kaum tawm mus rau pua pua ntawm micrometers. Tej txawv muaj tsis muaj dab tsi ua nrog rau qhov luaj li cas ntawm cov neeg laus.

Qhib ntawm cov phev

Ua ntej zaum xav txog cov nqe lus nug, "Qhov chaw uas yog cov phev ua?", Lawv twb tsis muaj lub tswv yim hais tias muaj tshwj xeeb hlwb muab kev koom tes nyob rau hauv lub tu tub tu kiv ntawm tib neeg beings thiab tsiaj txhu. Thiab nyob rau hauv Feem ntau cov qauv ntawm nyob ntaub so ntswg muaj heev me ntsis tswv yim.

Kiv puag ncig nyob rau hauv science tshwm sim nyob rau hauv nruab nrab ntawm lub thib kaum xya xyoo pua, thaum Antoine Dutchman Leeuwenhoek invented lub tshuab kuaj kab mob thiab ntsia nws txawv khoom: paj ntoos, nplooj thiab petals ntawm cov nroj tsuag, tib neeg thiab tsiaj daim tawv nqaij thiab ntau dua. Nyob rau hauv 1677, nws tuaj mus txog rau kab hlwb. Nws tau piav lub qe thiab cov phev, uas nws tau piav raws li "seminal tsiaj."

Zoo li tej tus paub txog, Leeuwenhoek ntej muab tso rau tag nrho cov thwmsim rau nws tus kheej, li ntawd, cov thawj tib neeg phev tau piav, thiab tsuas yog tom qab lwm yam tsiaj. Lub tswv yim hais tias cov "tsiaj" yog muab kev koom tes nyob rau hauv lub conception, sai sai tuaj rau Antoine lub taub hau, uas nws tsis tsis qhia rau tus British scientific lub zej lub zos.

Tab sis qhov no hypothesis tau tsis kam lees, thiab ib puas xyoo mas suav hais tias cab kab nyob rau hauv ib tug txiv neej lub cev, los yog muaj tsis muaj dab tsi rau fertilize. Tsuas yog nyob rau hauv thaum ntxov thib kaum cuaj caug xyoo, lub Italian Spallanzani muaj pov thawj qhov tseeb ntawm no ziag no.

qauv

Yog hais tias koj tsis coj mus rau hauv tus account qhov ntev ntawm lub flagellum, cov phev yog qhov tsawg tshaj plaws ntawm tes nyob rau hauv tib neeg lub cev, hais txog 55 micrometers. Cov me me qhov ntev cia nws tau tsiv mus nyob sai sai nyob rau hauv cov kab noj hniav ntawm lub tsev menyuam thiab ncav cuag lub qe.

Nyob rau hauv thiaj li yuav txawm tsawg nyob rau hauv lub tsim ntawm cov phev, lawv yauv mus ua ib tug series ntawm transformations:
- lub nucleus yuav ntau tuab los ntawm hws ntawm kev tshuaj ntsuam genetic cov khoom;
- cytoplasm yog cais rau ib tug nyias muaj nyias ib "cytoplasmic droplet";
- muaj tsuas yog cov organelles uas tseem ceeb heev rau lub cell.

1. Lub taub hau ntawm cov phev cell muaj tus duab ntawm ib ellipse, ib tug flattened laterally. Tej zaum nws yuav ua tau concave rau ntawm ib sab, thiab ces peb yuav tau tham txog cov ntawv nyhav diav. Nyob rau hauv lub taub hau yog:
   - ib tug tseem ceeb muaj ib tug haploid txheej chromosomes. Nws yog tsim nyog hais tias tom qab lub merger ntawm ob nrog txiv neej pw lub hlwb tag nrho cov nyiaj ntawm caj ntaub ntawv yog sib npaug zos rau hais tias ntawm lub Somatic hlwb, los yog lub fetus yuav tsis ciaj sia lossis yuav muaj deformities. Vim hais tias ntawm cov muaj zog "contraction" ntawm chromatin nws yog tsaug zog thiab tsis tau ua ke RNA.
   - acrosome - yog evolutionarily hloov Golgi apparatus, nws yog tsim nyog los xyuas kom meej tias lub taub hau ntawm cov phev yuav tau mus rau hauv lub qe.
   - centrosome - organelle, uas txhawb nqa lub "cell cev pob txha" thiab muab lub zog ntawm tus Tsov tus tw.
2. Qhov nruab nrab los yog lub caj dab - yog narrowing ntawm lub taub hau thiab tus Tsov tus tw. Nws yog ib lub mitochondria, uas tsim lub zog rau lub zog ntawm tus flagellum.
3. Tsov tus tw los yog flagellum - ib tug nyias rooj noj ib feem ntawm cov phev. Ua ib tug muab reciprocating tsab ntawv tsa suab, tas cov cell mus cuag lub hom phiaj.

muaj nuj nqi

Cov kev thiab spermatozoa chaw tsim yog zoo txog rau nws cov kev khiav dej num. Thiab lub qho tseem ceeb heev ntawm lawv - nws yog allergic mus rau hauv lub qe thiab fertilization. Yuav kom ua tau li no muaj nuj nqi, xwm tau muab muaj, loj thiab tshuaj "attractiveness" ntawm cov phev.

Txiv neej thiab poj niam cov kab mob no yog rau cov tu tub tu kiv ntawm lawv tus kheej zoo, ces lawv yuav tau tshaj lub cev, sib thiab txhob kaw. Yog hais tias ib tug txiv neej yuav siv sij hawm saib xyuas ntawm nws noj qab haus huv, muaj tsis muaj tsis tau phem, nyob rau hauv lub sij hawm ua kom tag nrho cov tshuaj txhaj (tshwj xeeb tshaj yog mumps), nws kab hlwb yuav tsum tau npaj ua nws txoj kev ua ntawm txhua lub sij hawm.

tsab ntawv tsa suab

phev tsim nyob rau hauv cov txiv neej yog vim, inter alia, nrog rau tsim ntawm flagella, uas yuav pab hlwb txav. Thaum lub sij hawm lub zog ntawm gamete yog rotated ib ncig ntawm nws axis ntawm ib tug ceev ntawm 0.1 millimeters ib ob. Nws yog xav paub ntau tshaj peb caug centimeters ib teev. Lawv yuav tsum mus them rau cov kev ncua deb ntawm 20 cm. Qhov chaw ib ob peb teev tom qab kev sib deev com, cov phev mus txog txoj hlab qe menyuam, thiab (yog hais tias muaj yog qe) fertilization tshwm sim.

Hauv cov phev ntawm txiv neej lub cev yog yuav luag tsis mus, lawv yuav tsis active thiab passively tsiv raws spermatic ducts, ua ke nrog seminal kua vim peristaltic taw ntawm cilia thiab ducts.

Lub neej luv ntawm cov phev

Zaum nrog tus physiologists tau sim nrog rau lo lus nug ntawm qhov chaw uas cov phev yog tsim thiab yog vim li cas lawv cov tshiab tsis tseg? Nws muab tawm hais tias tag nrho cov txheej txheem ntawm maturation ntawm gametes yuav siv sij hawm ntau tshaj li ob lub hlis, tiam sis lawv tau ib tug loj tus naj npawb. Raws li ib tug tshwm sim, cov txiv neej muaj muaj tsis txaus cov kev tshuaj ntsuam genetic khoom.

Cov nqi ntawm cov phev yog muab khaws cia tseg tsuas yog rau ib lub hlis, thaum lawv yuav tsum muaj txoj cai tej yam kev mob:
- lub kub saum toj no 32 degrees Celsius;
- lub qhaj ntawv ntawm inflammatory kab mob.

Tab sis sab nraum ntawm txiv neej lub cev, lub hlwb khaws lawv muaj txog li ib hnub twg. Hauv lub tsev me nyuam, lub sij hawm no tej zaum yuav ncua mus rau peb hnub.

Yuav ua li cas yog spermatogenesis?

Spermatogenesis - yog lub tsim ntawm cov phev, uas tshwm sim nyob rau hauv lub tsev kev cai ntawm lub cev endocrine system.

Nws tag nrho cov pib nrog progenitor hlwb, uas tom qab ob peb kev sib cais noj rau hauv daim ntawv ntawm ib tug neeg laus cov phev. Nyob ntawm seb lub hom ntawm cov phev maturation txheej txheem yuav txawv. Piv txwv li, nyob rau hauv chordates thaum lub sij hawm embryonic lub sij hawm muab tshwj xeeb hlwb uas migrate mus rau lub gonads thiab primordia daim ntawv pas dej ua ke ntawm hlwb, uas tom qab ua spermatozoa.

Spermatogenesis nyob rau hauv tib neeg

Cov kev rau txoj kev cov phev ib tug txiv neej tsis txawv li cas ntawm lwm cov vertebrates. Cov txheej txheem pib thaum tiav nkauj tiav nraug (hnub nyoog 12) thiab ncua yuav luag mus rau 80 xyoo.

Raws li ib qhov chaw, phev maturation voj voog kav 64 hnub, nyob rau lwm yam - mus rau 75 hnub. Tab sis ib tug kev hloov ntawm tubular epithelium (uas yog ib tug substrate rau lub tsev me nyuam hlwb) yog tsis tsawg tshaj ib zaug nyob rau hauv 16 hnub.

Tag nrho cov txheej txheem yuav siv sij hawm qhov chaw nyob rau hauv lub convoluted seminiferous tubules ntawm cov noob qis. Nyob rau hauv lub qab daus membrane ntawm tubules txheej txheem spermatogonia thiab spermatocytes ntawm tus thawj thiab thib ob kev txiav txim, uas ces qha mus rau hauv paub tab ntawm tes. Thawj progenitor hlwb mus los ntawm ob peb mus ntawm mitosis division, thiab thaum lawv txaus, hloov mus rau meiosis. Raws li ib tug tshwm sim ntawm no kawg faib ua ob tus ntxhais spermatocytes, thiab ces lwm ob spermatids. Txhua yam ntawm cov hlwb muaj ib nrab ntawm cov xov tooj ntawm chromosomes thiab yuav fertilize ib lub qe.