Qhov Tseem Ceeb Qhov txawv - Myelinated vs Unmyelinated Axons
Lub paj hlwb yog tus saib xyuas kev txais thiab faib cov cim kev hnov qab txhua qhov chaw hauv lub cev. Neurons yog lub tsev thaiv los yog lub hauv paus hlwb ntawm lub paj hlwb. Neurons yog lub luag haujlwm rau kev xa cov ntaub ntawv raug lossis cov lus txib kom kho qhov chaw ntawm lub cev. Lub neuron muaj peb lub ntsiab lus tseem ceeb: lub cev ntawm tes, dendrites, thiab axon. Dendrites tau txais hluav taws xob teeb liab thiab xa mus rau axon. Axon xa cov teeb liab mus rau lub neuron tom ntej. Axons yog insulated nrog ib txheej hluav taws xob insulator hu ua myelin sheath. Myelin sheath yog tsim los ntawm cov khoom siv fatty hu ua myelin. Myelin sheath yog tsim los ntawm tshwj xeeb peripheral paj hlwb hlwb hu ua Schwann hlwb. Myelin yog tsim los ntawm Schwann hlwb, thiab myelin sheath yog tsim nyob ib ncig ntawm lub axon nyob rau hauv ib tug kauv zam. Myelin sheath tsub kom qhov ceev ntawm lub teeb liab kis tau tus mob, tab sis tsis yog txhua txhua axons yog myelinated. Raws li lub xub ntiag thiab tsis muaj myelin sheath nyob ib ncig ntawm lub axon, muaj ob hom neurons. Lawv yog myelinated neurons thiab unmyelinated neurons. Myelinated neurons muaj myelinated axons, thiab unmyelinated neurons muaj unmyelinated axons. Qhov sib txawv tseem ceeb ntawm myelinated axon thiab unmyelinated axon yog tias myelinated axons muaj myelin sheath thaum unmyelinated axons tsis muaj myelin sheath.
Myelinated Axons yog dab tsi?
Ib qho axon yog qhov ntev ntev ntawm cov paj hlwb (neuron). Nws ua hluav taws xob impulses deb ntawm lub cev neuron cell mus rau cov tshuaj synapse. Axons tseem hu ua paj hlwb. Cov hlab ntsha impulses kis tau raws li axons txuas ntxiv yam tsis hloov nws txoj kev. Cells ntawm lub paj hlwb peripheral txhawb kev sib kis ntawm cov hlab ntsha impulses ntawm neurons.
Schwann hlwb yog ib hom tshwj xeeb glial hlwb uas tsim myelin sheaths nyob ib ncig ntawm lub axons. Myelin sheath yog ib txheej hluav taws xob insulating tsim los ntawm myelin protein thiab lipids, suav nrog cov roj cholesterol, glycolipids, thiab phospholipids. Neurons uas nws axons npog nrog myelin sheaths hu ua myelinated neurons. Axons uas tiv thaiv nrog myelin sheaths yog hu ua myelinated axons. Feem ntau, cov axons loj dua yog them nrog myelin sheaths, thiab lawv raug hu ua myelinated fibers lossis medullated fibers. Thicker axons muaj lub tsho tuab ntawm myelin thiab ntev internodes. Thaum axons yog myelinated, lawv saib dawb.
Daim duab 01: Myelinated axon
Myelin sheath yog muab los ntawm Schwann hlwb thiab Schwann hlwb khaws qhov khoob thaum qhwv ib ncig ntawm axon. Cov qhov khoob no yog unmyelinated. Yog li ntawd, myelin sheath yog cuam tshuam los ntawm cov qhov khoob no thiab lawv tau hu ua cov nodes ntawm Ranvier. Thaum axons yog myelinated, kev ua ntawm cov hlab ntsha pulses sai dua nrog cov neurons thiab nws tsis txhob poob ntawm impulse thaum lub sij hawm conduction.
Dab tsi yog Unmyelinated Axons?
Thaum axons tsis tiv thaiv nrog myelin sheaths, lawv hu ua unmyelinated axons. Feem ntau, thinner axons, uas tsawg dua ib micron inch, tsis muaj myelin sheaths nyob ib ncig ntawm lawv. Cov axons lossis paj hlwb no tseem hu ua non myelinated lossis non-medullated fibers. Kev ua ntawm cov hlab ntsha impulse los ntawm unmyelinated axon yog qeeb dua hauv myelinated axons. Kuj tseem muaj txoj hauv kev poob lub impulse thaum lub sijhawm ua haujlwm.
Daim duab 02: Unmyelinated Axon thiab Myelinated Axon
Qhov txawv ntawm Myelinated thiab Unmyelinated Axons yog dab tsi?
Myelinated vs Unmyelinated Axons |
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| Myelinated axons yog cov neuron axons uas tau npog nrog myelin sheaths. | Unmyelinated axons yog cov axons uas tsis npog nrog myelin sheaths. |
| nrawm ntawm Nerve Impulses | |
| Kev ua ntawm cov hlab ntsha impulses sai dua hauv myelinated axons. | Kev ua ntawm cov hlab ntsha impulse qeeb dua hauv cov axons uas tsis muaj myelinated. |
| Poob Impulses | |
| Kev poob ntawm impulses yog zam nyob rau hauv myelinated axons. | Muaj ntau txoj hauv kev poob impulses. |
| Thickness | |
| Myelinated axons yog thicker dua unmyelinated axons. | Unmyelinated axons yog thinner dua myelinated axons. |
Summary – Myelinated vs Unmyelinated Axons
Axon yog ib txoj xov zoo li txuas ntxiv ntawm cov neuron. Nws txuas los ntawm soma ntawm cov neuron. Axons xa hluav taws xob teeb liab tawm ntawm cov neuron. Hauv qee cov neurons, axons tau qhwv nrog cov hlwb tshwj xeeb hu ua Schwann hlwb. Schwann hlwb tsim ib txheej hluav taws xob insulating nyob ib ncig ntawm lub axon, uas yog hu ua myelin sheath thiab nws ua rau kom ceev ntawm lub teeb liab kis tau tus mob. Qee cov axons tsis muaj myelin sheaths. Lawv hu ua unmyelinated axons. Cov axons uas npog nrog myelin sheath yog hu ua myelinated axons. Qhov no yog qhov txawv ntawm myelinated thiab unmyelinated axons.
Download PDF Version of Myelinated vs Unmyelinated Axons
Koj tuaj yeem rub tawm PDF version ntawm kab lus no thiab siv nws rau offline lub hom phiaj raws li daim ntawv ceeb toom. Thov download PDF version ntawm no Qhov txawv Ntawm Myelinated thiab Unmyelinated Axons.
