Saturday, February 05, 2011

Ang nakakamanghang kwento ng mga enzymes

Nung highschool ay tinuro sa amin kung ano ang enzymes pero hindi ganun ka detalyado ang kwento kaya hindi ko sila gaanong na-appreciate. Ngayong mas biology papers ang mga binabasa ko ay lagi ko silang nakakasalubong sa mga binabasa ko. Medyo mahaba at madaming pasikot-sikot ang kwentong ito; maraming mga aspeto ng kwento na hindi pa natin alam, pero ang kabuuang kwento mula sa pagkabuhay hanggang sa pagkamatay ng mga enzymes ay nalaman na.

Ang kwentong ito ay maririnig natin mula sa mga cells na may nucleus; may mga cells na walang nucleus tulad ng mga bacteria at ng red blood cells natin. Tulad ng iba pang mga proteins, ang buhay ng mga enzymes ay nagsimula sa DNA sa loob ng nucleus. Ayon sa kwento, isang malaking enzyme katulong ang iba pang maliliit na enzymes ang pumupunta sa DNA at mula dito ay binubuo nila ang mga RNA. Ilan sa mga RNA na ito ay mananatili lang sa loob ng nucleus, pero ang iba ay lalabas mula dito sa tulong na rin ng ilang proteins na nakatira sa bakod ng nucleus (nuclear membrane). Ang mga messenger RNA (mRNA) ay magpapatuloy sa cytoplasm at dito sila ay magpapalutang-lutang. Makakasalubong nila ang ilang enzymes at iba pang molecules sa cytoplasm, pero may mga specific proteins na eventually ay makakasalubong nila na gagabay sa kanila papunta sa pagawaan ng proteins. "Hi mRNA, halika dito tayo pumunta," sabi ng malaking protein na ito.



At dito uusbong ang isang protein na later on ay magiging enzyme. Ang bagong-gawang protein na ito ay magpapalutang-lutang na naman sa cytoplasm, naghihintay ng pagbabago sa kanilang katawan (post-translational modification) at itsura (protein folding) para sila ay magkakaroon ng specific na gawain. Hangga't hindi pa nababago ang itsura nito, hindi pa nito maipapamalas ang kanyang potential. So sa ilang saglit ay makakasalubong nito ang isa o marami pang enzymes na magpapabago sa itsura nito; ang mahabang sequence ng amino acids na bumubuo sa protein na ito ay aayusin ng mga particular na enzymes para ang buong protein ay magkakaroon ng specific na hugis na syang kailangan para makapagsimula na itong gampanan ang kanyang gawain.



Ang bawat enzyme ay may kanya-kanyang gawain, pero sa kabuuan, ang gawain nila ay baguhin ang itsura at komposisyon ng mga proteins at iba pang molecules. May mga enzymes na magdidikit ng dalawa o mas marami pang molecules, meron ding mga enzymes na magpapabago sa hugis ng molecules.

Ang kanilang buhay ay panandalian lamang; ang tagal nito ay depende sa kanilang komposisyon ng amino acid at hugis. Dadating ang panahon na makakasalubong nila ang isang uri ng protein na magsasabi sa kanila na mag-retire na (ubiquitination). Minsan naman ay sasabihan din sila ng mga ubiquitins na magbago na sila ng gawain at sila ay ipapadestino sa ibang parte ng cell.

Ang dulo ng kwento ay ang kanilang kamatayan. Pagkatapos ng isang panahon ng pag-gampan ng gawain, pagtulong sa iba pang proteins, at pakikihalubilo sa iba pang enzymes at iba pang molecules, sila ay magreretire na. Sila ay bibiyakin ng ibang proteins at ang kanilang mga amino acids ay gagamitin muli sa susunod na pagbubuo ng mga bagong enzymes.


Link

Sunday, January 30, 2011

Paglilinaw: HINDI po ako kasama dun sa mga nakipag-girian sa mga police

Student protesters in Holland clash with policemen
By Dheza Marie Aguilar
ABS-CBN Europe News Bureau
01/29/2011

THE NETHERLANDS - In what was said to be the biggest student demonstration in the Netherlands since 1988, an estimated 15,000 students gathered in The Hague on Friday afternoon to protest against the planned budget cut for higher education.

Earlier in the day, hundreds of professors from different universities in the Netherlands also walked around the parliament dressed in their togas to support the budget cut protest.

But what started as a peaceful demonstration in Malieveld Park ended in a scuffle against the demolition police when about 500 students marched in front of the Ministry of Education where they were met with trucks and policemen on horseback. Volunteers also formed a barricade outside the building to prevent the protesters from storming in.

The situation worsened when protesters began hurling beer cans, bicycles, eggs and fireworks at the policemen. The police retaliated by chasing the rioters and hitting some with batons.

Twenty-five protesters were arrested, some of which, the police claimed, were part of radical groups. Before the Friday rally, the police announced that anti-fascist and radical groups are planning to distort the demonstration prompting them to increase security deployment.

A fine of 3000 euros and more

The biggest issue confronting the academic sector in the planned budget cut is the 3000-euro fine that a student must pay if he or she studied a year longer than the allowed time in finishing his or her degree.

Aside from the students, universities are also mandated to pay the same amount for every student who will study longer than necessary.

Argued the protesters, many students fully developed themselves in activities outside the mandatory curriculum like in management of student’s association, internship abroad or organization of student’s congress. They said that these are also important for companies when assessing them for future jobs.

Meanwhile according to universities, the budget will result in a loss of 7,000 jobs in their sector and a lower quality of education.

“Working class youth already don't have the money to go to a university and that won't change with the upcoming laws. That's why I want a free education of good quality for everyone. Also we are only being given information just by reading books, instead of showing the 'real life' practical experiences. I think that's because our society is too much based on the profit maximization,” said Thomas van Beersum of Hermann Wesselink College in Amstelveen.

He added that a lot of young people will not be motivated to get higher education because of the high expenses that it entails.

Aside from the fines, the government is also planning to scrap student grant and those who are planning to take their second masteral degree have to pay for it themselves. This means an expense of 15,000 euros every year for students planning on having their second masteral degree.

In addition to these major changes, the free use of public transport for students will be discontinued.

It is estimated that 20% of the total budget cut that the parliament is planning will fall on the academe.

“A free education should be an investment that will be given back later when people have a steady job and a good income,” van Beersum added.

In the current system every student who gets a bachelor’s degree receives a financial grant from the government. Outside those six years, if a student wants to pursue a masteral degree, he or she can get a study loan from the government. This is payable after he or she gets a job and income that will enable him or her to pay the government. But some students take 11 years to finish school.

If implemented as planned, overstaying students will immediately be fined this coming September.

Support for the academe

To show support and solidarity with the Dutch academe, some Filipino students joined the Friday rally.

Hiyasmin Saturay, daughter of a refugee who wants to enter a Dutch university next year, said the government should focus instead on helping students get a better quality of education. In recent years, the Dutch ranking in the list of the world’s top quality education continues to slide.

“Nandito ako ngayon para makiisa sa mga estudyante para tutulan ang pinaplano ng gobyerno na pinapagbayad ang estudyante ng lumalagpas sa study nila. Ang lumalabas, sila 'yung nagbabayad sa mga kakulangan ng gobyerno sa quality ng education, sa mali sa economy. Maghihirap ang mga estudyante. Ano na ang mangyayari sa kinabukasan nila?” said Saturay.

Meanwhile Kim Gargar, a Filipino scholar studying in Groningen, joined the protest to heed the call of the academe to oppose the budget cut.

“Pumunta ako dito para makiisa sa Dutch academic community. Isyu naman talaga nila ito although sa atin talaga mas malaki ang problema ng academe kaya kailangan ng international solidarity na din sa mga kapwa natin academecian dito sa Netherlands,” said Gargar.

No abrupt change

The rally showed most protesters waving “Op-Rutte” banners to criticize the policies of the new government led by Prime Minister Mark Rutte.

In his speech during the evening of the demonstration, Rutte said there will be no abrupt changes in the new education policies that they are pushing. He said the budget cut is necessary in order to bring the government’s finances in order.

The prime minister also appealed to the universities to use their reserve funds to alleviate the effect of the budget cut.

Link

Sunday, December 05, 2010

Natutunaw

Nagising ako mga alas-kwatro ng madaling araw dahil sa lakas ng tunog ng tagaktak ng tubig sa sahig. Dumadagundong ang pagbagsak ng isang tulo ng tubig kada ilang segundo. Bumangon ako at hinanap ang basahan para saluhin ang mga tulong nanggigising. Pagkatapos ay bumalik sa higaan at ipinagpatuloy ang paghihilik. Umakyat na naman pala lampas sa zero celsius ang temperatura.

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