Membran Sel
Membran sel sering juga disebut membran plasma. Membran sel merupakan bagian paling luar yang membatasi isi sel dengan sekitarnya (kecuali pada sel tumbuhan, bagian luarnya masih terdapat dinding sel atau cell wall).
Membran sel berupa lapisan luar biasa tipisnya. Tebalnya kira-kira 8 nm. Dibutuhkan 8000 membran sel untuk menyamai tebal kertas yang biasa kita pakai untuk menulis.
Lipid dan protein merupakan bahan penyusun utama dari membran, meskipun karbohidrat juga merupakan unsur penting. Gabungan lipid dan protein dinamakan lipoprotein. Saat ini model yang dapat diterima untuk penyusunan molekul-molekultersebut dalam membran ialah model mosaik fluida.
Pada 1895, Charles Overton mempostuatkan bahwa membran terbuat dari lipid, berdasarkan pengamatannya bahwa zat yang larut dalam lipid memasuki sel jauh lebih cepat dari pada zat yang tidak larut dalam lipid. 20 tahun kemudian, membran yang diisolasi dari sel darah merah dianalisis secara kimiawi ternyata tersusun atas lipid dan protein, yang sekaligus membenarkan postulat dari Overton.
Fosfolipid merupakan lipid yang jumlahnya paling melimpah dalam sebagian besar membran. Kemampuan fosfolipid untuk membentuk membran disebabkan oleh struktur molekularnya. Fosfolipid merupakan suatu molekul amfipatik, yang berarti bahwa molekul ini memiliki daerah hidrofilik (menykai air) maupun daerah hidrofobik (takut dengan air).
Berdasar struktur tersebut maka membran sel bersifat semi permeable atau selektif permeable yang berfungsi mengatur masuk dan keluarnya zat dari sel.
Gbr. Membran Sel
Paket Biologi Terlengkap. Klik!
good blog.awesome
Comment by robert — July 14, 2008 @ 10:02 pm
wah, saya belajar boi jadi lebih asik…..makasih
Comment by indonesianheri — August 5, 2008 @ 3:21 pm
wah,,,,,
gmbr nya keyen tuh….
he,,,,he,,,,he
Comment by wiwid — October 14, 2008 @ 11:45 am
sangat bagus………….
belajarpun jadi lebih asyik..
Comment by Azis — October 30, 2008 @ 2:54 pm
I can enjoy studyinng, thanks a lot
Comment by edi wahyudi — December 25, 2008 @ 7:10 pm
very interest and very good
Comment by guntur — May 16, 2009 @ 8:51 am
bagus bgt puas bgt ma gambar and penjelasannya tuch, salam sukses tah….
Comment by dhyna — June 15, 2009 @ 5:41 pm
good bgt
Comment by dhyna — June 15, 2009 @ 5:46 pm
bagus
sangat membantu untuk keg blajar saya
Comment by aldi — July 22, 2009 @ 6:39 pm
mANTaP …….TeNaN
BeLaJaR PUn SemAkIN seMaNGat^_^.
Comment by WAkEy — September 5, 2009 @ 4:17 pm
Wah,, isinya menarik, di lengkapi dengan gamber animasi juga, jadi lebih mudah untuk memahami
Comment by zulfikar — March 3, 2011 @ 6:21 am
The Relentless Pursuit of Perfection.
Comment by coach bag outlet — September 7, 2011 @ 6:29 pm
I hope you will keep updating your content constantly as you have one dedicated reader here.Hey this is a great post. I’m going to email this to my buddies. I stumbled on this while googling for some lyrics, I’ll be sure to come back. thanks for sharing.
Comment by Buy Zentai Suit — September 21, 2011 @ 5:38 pm
wah jadi seru belajar tentang biologi..pngen memperdalam lagi ilmu-ilmu biologi…
Comment by m.salamun — April 21, 2012 @ 6:56 pm
bagus,,,,,,and kerennnnnnnnnnn,,,,,,
Comment by putri — April 26, 2012 @ 9:02 am
I am generally to blogging and i really recognize your content.
That the article has actually peaks my interest.
I am going to bookmark your web site and maintain checking for brand new information.
Comment by payday loans — November 8, 2012 @ 9:39 pm
A first-rate obvious cut answer and a great concept. Then again how do I post any work on this website is an
additional question. The Foureyed Poet.
Comment by reverse phone lookup free — November 30, 2012 @ 2:00 am
I do not know if it’s just me or if everyone else
encountering issues with your site. It appears because if some of that the written text within your
content have been running off the screen. Can somebody else please comment and let me recognize if this is happening to them as well?
This might be a question with my browser because I’ve had this happen before.
Cheers
Comment by criminal background check — December 1, 2012 @ 5:51 am
I such as what you guys have been up too. Such smart work and reporting!
Carry on the superb works guys I?ve incorporated you guys to my blogroll.
I think it will improve that the value of my web site
Comment by cell phone lookup — December 3, 2012 @ 6:59 am
Were required to offer you that almost no remark in order to thanks a ton yet again
of these spectacular techniques you might have provided in this posting.
It’s so particularly generous with folks such because you to generate unreservedly what the majority of us might have marketed for an book to earn some money in their own business,
primarily since it is possible to have tried it in the event you wanted.
The tactics also acted to be fine route to identify that everyone’s similar desire just
because my own, personal to find out completely more regarding this condition.
I’m sure there are thousands of more pleasant
opportunities up front for quite a lot of who go through your website post.
Comment by background check — December 16, 2012 @ 3:50 am
Nice post. I understand something tougher on different blogs
everyday. Most commonly it can be stimulating you just read content
off their writers and use a little something there. I’d select to apply certain together with that the content on
my blog regardless of whether or not you don’t mind.
Natually I’ll give out a link for your internet blog. Lots
of thanks sharing.
Comment by how to get your ex back — December 29, 2012 @ 4:35 pm
I will immediately grasp your rss as I can not find your e-mail subscription link or e-newsletter
service. Do you’ve any? Kindly allow me know so that I may subscribe.
Thanks.
Comment by how to lose weight during menopause — January 4, 2013 @ 6:01 pm
I’m sure your publish and internet site is incredibly constructed
Comment by free cell phone lookup ontario canada — January 5, 2013 @ 11:15 pm
There are some attention-grabbing closing dates in this article in spite of this I
don identify if I see all of them heart to heart.
There may be some validity however I will take hold opinion until I look
into it further. First-rate article , thanks
and we wish more! Added to FeedBurner because well
Comment by live people search — January 6, 2013 @ 1:31 am
Great post. I was checking continuously this blog and
I am impressed! Very useful info specially the last part :
) I care for such information much. I was seeking this particular info for a very
long time. Thank you and best of luck.
Comment by best loans — January 12, 2013 @ 7:42 pm