Qhov sib txawv tseem ceeb ntawm myofibrils thiab sarcomeres yog tias myofibrils yog cov chaw cog lus ntawm cov leeg thaum sarcomeres yog cov rov ua dua me me ntawm myofibril.
Cov leeg pob txha muaj myofibrils. Lawv tsim los ntawm myocytes. Qhov rov ua dua ntawm cov leeg pob txha yog myofibril. Ib yam li ntawd, qhov rov ua dua ntawm myofibril yog sarcomere. Sarcomere ua haujlwm thaum lub sijhawm cog lus thiab so ntawm cov leeg. Lawv nquag ua haujlwm thaum txav mus los thiab tsis tshua muaj zog ntawm cov xwm txheej sedentary.
Myofibrils yog dab tsi?
Myofibrils yog cov qauv ntawm cov leeg nqaij. Lawv yog cov qauv zoo li tus pas nrig. Myocytes ua rau myofibrils. Myogenesis yog txheej txheem ntawm kev tsim cov leeg nqaij thiab myofibrils. Nws tshwm sim thaum lub sij hawm embryonic txoj kev loj hlob. Cov protein sib txawv, suav nrog actin, myosin thiab titin, tsim myofibrils. Txawm li cas los xij, actin thiab myosin ua lub luag haujlwm tseem ceeb hauv myofibrils. Myofibrils kuj muaj cov khoom siv ntxiv uas khi cov protein ntau ua ke.
Daim duab 01: Myofibrils
Muaj ob hom myofilaments hauv myofibrils. Lawv yog cov nyias thiab tuab myofilaments. Cov filaments nyias yog actin filaments thaum tuab filaments yog myosin filaments. Lawv npaj rau hauv cov chav nyob rov ua dua hu ua sarcomere, uas ua haujlwm thaum lub sij hawm lub cev nqaij daim tawv thiab cov leeg mob. Yog li, lub luag haujlwm tseem ceeb ntawm myofibrils yog los pab txhawb kev cog lus ntawm cov leeg nrog kev pab ntawm calcium, troponin thiab tropomyosin. Nws tshwm sim los ntawm kev sib kis ntawm cov hlab ntsha impulse. ATP yog qhov tseem ceeb rau txoj haujlwm no. Yog li, cov leeg nqaij contraction yog ib qho kev siv zog.
Sarcomeres yog dab tsi?
Sarcomeres yog qhov rov ua dua ntawm myofibrils. Lawv structurally muab cov tsos striated rau cov pob txha pob txha thiab cov leeg plawv. Sarcomeres muaj ob qhov tseem ceeb ntawm cov protein filaments uas swb dhau ib leeg thaum so thiab contraction. Lawv yog cov actin filaments thiab myosin filaments. Nyob rau hauv lub sarcomere, cov actin filaments tsim nyias bands, thiab myosin filaments tsim tuab bands. Lawv tsuas muaj nyob rau hauv cov leeg mob plawv thiab pob txha pob txha thiab tsis nyob hauv cov leeg nqaij.
Daim duab 02: Sarcomere
Txhua tus sarcomere hauv myofibril yog sib cais ntawm ib leeg ntawm Z kab. Z kab yog qhov chaw nres nkoj rau actin filaments. Tom ntej no mus rau Z kab, I band yog tam sim no. Ntawm no, I band tsuas muaj nyias nyias. Nws tsis muaj superimposed tuab filaments. Lub A band nyob ib sab ntawm I band. Lub A band tsuas muaj tuab filaments thiab nyias filaments. Ua raws li A band, H zone yog thaj chaw uas tsuas yog cov tuab tuab. Cov kab M nyob rau hauv H cheeb tsam tsim kev sib txuas ntawm cov cytoskeleton. Yog li, lub luag haujlwm tseem ceeb ntawm sarcomere yog pab txhawb cov leeg nqaij thiab so hauv cov leeg pob txha thiab lub plawv.
Dab tsi yog qhov zoo sib xws ntawm Myofibrils thiab Sarcomeres?
- Ob leeg muaj cov proteins, xws li actin thiab myosin.
- Lawv tseem ceeb hauv cov leeg nqaij.
- Ob leeg xav tau Calcium thiab ATP rau cov txheej txheem ntawm kev cog lus.
- Ntxiv mus, lawv tseem ceeb hauv kev txav thiab txav chaw.
Qhov txawv ntawm Myofibrils thiab Sarcomeres yog dab tsi?
Myofibrils yog cov qauv ntawm cov leeg nqaij, qhov sarcomeres yog cov qauv ntawm cov myofibrils. Yog li, qhov no yog qhov sib txawv tseem ceeb ntawm myofibrils thiab sarcomeres. Tsis tas li ntawd, txawm hais tias lawv ua tau zoo ib yam, muaj qhov sib txawv ntawm myofibrils thiab sarcomeres nyob rau hauv lawv cov tsos nyob rau hauv lub electron microscope.
Ntxiv mus, myofibrils yog dav dav rau tag nrho peb hom ntawm cov leeg nqaij, thaum sarcomeres tsuas yog pom hauv cov leeg plawv thiab pob txha. Tsis tas li ntawd, lub xub ntiag ntawm sarcomeres muab cov tsos mob ntawm cov leeg no.
Cov duab hauv qab no nthuav tawm cov ntaub ntawv ntxiv txog qhov sib txawv ntawm myofibrils thiab sarcomeres.
Summary – Myofibrils vs Sarcomeres
Myofibrils yog cov qauv thiab kev ua haujlwm ntawm cov leeg nqaij fiber ntau uas tsim cov leeg. Hauv cov pob txha pob txha thiab cov leeg nqaij, cov sarcomeres tsim cov kab sib tw, uas kuj yog qhov rov ua dua ntawm myofibril. Ua ke, lawv ua cov txheej txheem ntawm cov leeg nqaij contraction thiab so nrog kev pab los ntawm calcium, ATP thiab lwm yam binding proteins. Lawv cov kev ua yog neurogenic. Yog li, qhov no qhia txog qhov sib txawv ntawm myofibrils thiab sarcomeres.
