TsimSecondary kev kawm ntawv thiab cov tsev kawm ntawv

Yuav ua li cas yog tus kav? Tus qauv thiab cov ntsiab lus ntawm cov kav

Yuav ua li cas yog tus kav? Nyob rau hauv cov nqe lus ntawm biology, nws yog ib feem ntawm cov nroj tsuag, nyob rau hauv uas cov nplooj thiab paj, uas yog ib tug continuation ntawm lub vascular system, yos rov qab mus rau cov hauv paus hniav. Lub ntsiab muaj nuj nqi ntawm cov kav yog qhov tus me nyuam dej thiab zaub mov tseem ceeb ntawm cov av rau cov nplooj thiab lwm qhov chaw ntawm cov nroj tsuag. Ntsuab stems yog tseem lub luag hauj lwm rau cov zaub mov thiab koom nyob rau hauv photosynthesis.

Qia: nws cov qauv thiab cov ntsiab lus

Cov ntaub so ntswg ntawm lub kawg ntawm lub qia hlwb muaj peev xwm ntawm paub faib thiab ua nws elongation, hu ua lub apical meristem. kav khaubncaws sab nraud povtseg xws li cov epidermis - nws yog coated nrog ib tug txheej txheej ntawm tshwj xeeb hlwb zaub ciab, uas muab kev tiv thaiv los ntawm cov ib puag ncig. Thawj cov ntaub so ntswg khi epidermis thiab puab phloem lub luag hauj lwm rau cov ceevxwm uas cov khoom ntawm photosynthesis los ntawm cov nroj tsuag. xylem cov ntaub so ntswg partitioned dej thiab minerals los ntawm cov keeb kwm mus rau lub heev sab saum toj, yog li muab cov yam ntxwv them nyiaj yug rau cov nroj tsuag. Fabrics yog cambium txheej faib ntaub so ntswg tso cai lawv txoj kev loj hlob lub cev loj hlob nyob rau hauv dav. Tus nqi kav yog feem ntau los muab tseem ceeb heev tshuaj tag nrho nroj tsuag. Yog hais tias nws puas tsuaj los yog cov seem txeej ntaub qhwv, thaum lub sij hawm, deprived ntawm cov zaub mov ntaub so ntswg, maj mam pib qhuav li. Tag nrho cov tsis muaj tshwm sim nrog lub cem deb ntawm lub hauv paus system. tus kav feem kuj muaj xws li ib tug tub ntxhais uas yog lawm ua tus sau nrog ntxhov nroj tsuag qub zog ntoo xylem fibers thiab siv tau rau kev qhia kom paub ntawm cov nroj tsuag. Nws yuav ua tau khoom los yog hollow. Nws tus ntoo khaub lig seem yuav ua tau puag ncig, voos los yog lub hnub qub-puab.

Sab nrauv nta

Yuav ua li cas yog lub qia thiab seb nws zoo li cas? Lub sab saum toj ntawm lub kav yog nws cov ntsiab point ntawm kev loj hlob. Receptors nyob therein yuav tsum tau nthuav tawm nyob rau hauv daim ntawv ntawm nplooj buds thiab vegetative deev buds. Nyob rau hauv kev ntau yam nroj tsuag apical lawm auxin cheeb qhov uas cov kev loj hlob ntawm sab buds, li no kom paub tebchaws cov nroj tsuag, tsis mus rau lub sab. Yog hais tias lub apical kev ua paj yog muab tshem tawm thaum lub sij hawm pruning, lub loj hlob ntawm cov nplooj axils sab buds yuav tsim ntau nquag, thiab cov kav yuav bushy zoo. Raws li txoj cai, npog lub sab saum toj ntawm lub hloov los xij - paj dos, uas pab tiv thaiv. Cov tawv yog sab kev tiv thaiv cov ntaub so ntswg ntawm ntxhov nroj tsuag, thiab npaj nrog lub hnub nyoog.

vascular system

Lub vascular system yog sawv cev los ntawm ib tug network ntawm cov kav dej los ntawm kev uas cov dej thiab cov as-ham thauj thoob plaws hauv cov nroj tsuag los ntawm combining cov hauv paus hniav, qia thiab nplooj. Tsis tag rau cov muaj peev xwm khav xws li mosses thiab algae yog powered by diffuse. Leeg tshav nroj tsuag muaj xws li flowering thiab coniferous nroj tsuag thiab ferns. Lub system muaj ob lub ntsiab ntaub so ntswg: lub phloem thiab xylem. Xylem yog ib tug network ntawm cov kav dej uas thauj cov dej thiab minerals thoob plaws hauv lub nroj tsuag. Nyob rau hauv tas li ntawd, nws kuj muaj ib theem nrab muaj nuj nqi - ntxwv them nyiaj yug, nws yuav muab piv nrog rau cov txha nqaj qaum, uas yuav pab kom upright. Cov kev ntxhib los mos ntawm lub kav feem ntau nyob rau tus nqi ntawm cov ntaub so ntswg, piv txwv li, nws yog heev npaum li cas muaj nyob rau hauv lub tsob ntoo trunks, nyob rau hauv cov xim ntawm nws me npaum li cas.

Common ntawm ntau yam stems

  1. Ntoo. Ntawm no yog hais txog mas loj hlob ntoo nrog ib tug kuj loj cov tub ntxhais, thiab fab (roses, txiv quav ntswv nyoos, blackberries, raspberries).
  2. Hloov. Piv txwv li, tulips, lilies thiab nyo hau yog nyeem tas underground kav nrog fleshy nplooj. Nyob rau hauv gladiolus luv luv, nyeem tas underground qia nrog luv luv kuj nplooj. Lub compressed tub ntxhais, loj hlob saum toj no thiab hauv qab no cov keeb kwm ntawm cov nplooj thiab paj muaj ib tug pos nphuab, dandelion, African violet.
  3. Kab rov tav. Piv txwv li, lub sim saum nruab ntug tua ntawm pos nphuab, Toffee.
  4. Curly stems (hops, honeysuckle, ntsuab taum).
  5. Hom ntawm stems kuj muaj xws li tuber, xws li cov qos yaj ywm.
  6. Tuberous kav, luv luv thiab flattened, yog muaj nyob rau begonias, dahlias. Nyob rau hauv sib piv rau lub tubers, uas yog ua li khiav ri receptors, tuberous stems muaj tsuas yog tus nplooj buds nyob rau saum toj.

kav muaj nuj nqi

1. Nws txhawb cov nplooj, paj thiab txiv hmab txiv ntoo, tham lawv nrog rau keeb kwm. Tsob ntoo thiab nroj ntsiab kav los yog lub cev yog yus muaj los ntawm ib tug muaj zog columnar qauv.

2. Nws yog ib tug neeg xyuas pib ntawm dej, as-ham thiab photosynthesis khoom. Nws thauj system yog teem li ntawd, hais tias nws yuav tau ntsug thiab sab zog hauv cov nroj tsuag lub cev.

3. Muaj peev xwm mus khaws dej thiab cov khoom ntawm photosynthesis yog ib tug tseem ceeb heev muaj nuj nqi ntawm lub ntsug tus kav ntawm cov nroj tsuag xws li xibtes thiab cacti.

4. Cov ntsuab kav plays ib tug me luag hauj lwm nyob rau hauv khoom noj khoom haus ntau lawm vim rau tus txheej txheem ntawm photosynthesis, tab sis nyob rau hauv ib co hom (e.g., cacti) yog lub ntsiab pas nrig photosynthetic hloov khoom nruab nrog.

5. Nws yog ib tug txhais tau tias ntawm asexual tu tub tu kiv rau hauv ntau hom ntawm cov nroj tsuag, nrog rau cuttings.

tus kav ib feem

Tag nrho cov stems ntawm angiosperms, xws li cov neeg uas hnyav ncawv hloov, muaj ntshav, internodes, buds thiab nplooj. Ntawm - qhov no yog qhov point ntawm uas loj hlob rau hauv cov nplooj los yog buds. Zajlus hu ua interstice therebetween. Pib tawg paj - yog embryonic kav uas muaj lub peev xwm rau txoj kev loj hlob thiab kev loj hlob. Nws yuav loj hlob mus rau hauv ib lub paj los yog nplooj. Cov buds raug xa mus rau raws li nplooj buds, buds thiab buds tov. Muaj ntau ntawm lawv nyob twj ywm thaum so rau ib tug tej lub sij hawm, ces loj hlob mus rau hauv nyias muaj nyias ib qhov chaw los yog kev lawm mus rau hauv kav cov ntaub so ntswg thiab yog inconspicuous. Tsob ntoo thiab shrubs, sib nrug los ntawm lub ntsiab kav, feem ntau kuj muaj sab ceg, uas yog txuas mus rau lub me ceg. Nyob rau hauv tas li ntawd cov nplooj thiab buds, thiab lwm yam tej zaum yuav tam sim no nyob rau hauv daim ntawv ntawm cov plaub hau zoo li outgrowths yog epidermal hlwb, thiab stipules spikes.

kav ntev

Teb rau ib lo lus nug txog dab tsi yog tus kav, nws yog ib qho tseem ceeb los kuj xav txog nws loj. Rau tag nrho cov nroj tsuag, feem ntau nws yog lub aboveground ib feem, uas yuav muab yam ntxwv kev pab txhawb nqa thiab ua hauj lwm pab raws li ib tug Neeg Nruab Nrab thiab daim ntawv qhia ntawm lub hauv paus system thiab nplooj. Lub stems sib txawv loj ntawm ib tug me me rostochku hmab mus txog 15 'meter' inch tsob ntoo!

nqi

Yuav ua li cas yog tus kav? Peb yuav hais tias qhov no yog lub hauv paus axis, uas yog txuas tag nrho cov lwm yam lus. Feem ntau cov nroj tsuag uas muaj nyob rau saum toj no qhov chaw, tab sis nyob rau hauv ib co hom yuav tsum tau muab zais underground kav. Nws cov qauv thiab cov ntsiab lus yog inextricably txuas. Vim lub cim qauv ntawm dej thiab as-ham uas yog tauj rau cov nplooj thiab cov keeb kwm. Qhov tseem ceeb ntawm cov kav tsis tau overemphasized, thaiv cov hlab no tseem ceeb heev leeg ua rau tuag ntawm cov nroj tsuag. Muaj ntau ntau possibilities uas muaj daim ntawv thov, xws li ntoo (cav taws, lumber). Nws kuj yog ib tug nplua nuj qhov chaw ntawm sis plawv hniav rau papermaking, nyob rau hauv tej yam hom stems tej zaum yuav ib qhov chaw ntawm kev noj haus. Nws fibers nyob rau hauv cov nqaij nyoos daim ntawv no yeej yog ib feem ntawm cov tshuaj, latex, tannins, xim thiab ntau npaum li cas. Ib txhia hom stems yog siv rau cov asexual los yog vegetative tu tub tu kiv ntawm cov nroj tsuag.

Ib tug lossis loj tus naj npawb ntawm daim ntaub ntawv

Muaj ntau txhiab tus cov tsiaj ntawm cov nroj tsuag uas nws stems yog tseem ceeb heev rau ua liaj ua teb, xws li qos yaj ywm. Ntsug tus kav ntawm qab zib pas nrig yog lub ntsiab qhov chaw ntawm qab zib. Maple qab zib yog ua los ntawm maple yeej. Zaub siv cov ntsug tus kav ntawm asparagus, xyoob tua, Kohlrabi thiab dej chestnut. Ntsim cinnamon - yog tawv. Cov pos hniav Arabic yog ib cov zaub mov additive muab los ntawm acacia yeej. Chicle - qhov no yog qhov tseem ceeb muaj ntawm kev zom khoom ntawm cov pos hniav, rho tawm los ntawm lub chicle tsob ntoo. Los ntawm xyoob mus ua daim ntawv, rooj tog zaum, tej nkoj nquam, seev suab paj nruas, nuv ntses rods, kav xa dej thiab txawm ua vaj tse. Cork yog tau los ntawm cov tawv ntoo ntawm cov cork ntoo qhib. Rattan yog siv rau cov rooj tog thiab baskets ua los ntawm lub stems ntawm cov teb chaws sov xibtes ntoo. Lub earliest piv txwv ntawm cov kev siv ntawm no tseem ceeb heev ib feem ntawm cov nroj tsuag yog cov papyrus, nrov nyob rau hauv ancient Egypt. Amber - yog petrified kua ntoo los ntawm tsob ntoo trunks, siv rau kho kom zoo nkauj thiab tej zaum yuav muaj qhov seem ntawm ancient cov tsiaj. Cob los ntawm coniferous ntoo siv rau zus tau tej cov Turpentine thiab rosin.

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