Other Free Encyclopedias » Science Encyclopedia » Science & Philosophy: Ambiguity - Ambiguity to Anticolonialism in Middle East - Ottoman Empire And The Mandate System


anabolic cell catabolism reactions

Anabolism, or biosynthesis, is the process by which living organisms synthesize complex molecules of life from simpler ones. Anabolism, together with catabolism, are the two series of chemical processes in cells that are, together, called metabolism. Anabolic reactions are divergent processes. That is, relatively few types of raw materials are used to synthesize a wide variety of end products. This results in an increase in cellular size or complexity—or both.

Anabolic processes produce peptides, proteins, polysaccharides, lipids, and nucleic acids. These molecules comprise all the materials of living cells, such as membranes and chromosomes, as well as the specialized products of specific types of cells, such as enzymes, antibodies, hormones, and neurotransmitters.

Catabolism, the opposite of anabolism, produces smaller molecules used by the cell to synthesize larger molecules, as will be described below. Thus, in contrast to the divergent reactions of anabolism, catabolism is a convergent process, in which many different types of molecules are broken down into relatively few types of end products.

The energy required for anabolism is supplied by the energy-rich molecule adenosine triphosphate (ATP). This energy exists in the form of the high-energy chemical bond between the second and third molecule of phosphate on ATP. ATP's energy is released when this bond is broken, turning ATP into adenosine diphosphate (ADP). During anabolic reactions, the high-energy phosphate bond of ATP is transferred to a substrate (a molecule worked on by an enzyme) in order to energize it in preparation for the molecule's subsequent use as a raw material for the synthesis of a larger molecule. In addition to ATP, some anabolic processes also require high-energy hydrogen atoms that are supplied by the molecule NADPH.

Although anabolism and catabolism occur simultaneously in the cell, the rates of their chemical reactions are controlled independently of each other. For example, there are two enzymatic pathways for glucose metabolism. The anabolic pathway synthesizes glucose, while catabolism breaks down glucose. The two pathways share 9 of the 11 enzymatic steps of glucose metabolism, which can occur in either sequence (i.e., in the direction of anabolism or catabolism). However, two steps of glucose anabolism use an entirely different set of enzyme-catalyzed reactions.

There are two important reasons that the cell must have separate complementary anabolic and catabolic pathways. First, catabolism is a so-called "downhill" process during which energy is released, while anabolism requires the input of energy, and is therefore an energetically "uphill" process. At certain points in the anabolic pathway, the cell must put more energy into a reaction than is released during catabolism. Such anabolic steps require a different series of reaction than are used at this point during catabolism.

Second, the different pathways permit the cell to control the anabolic and catabolic pathways of specific molecules independently of each other. This is important because there are times when the cell must slow or halt a particular catabolic or anabolic pathway in order to reduce breakdown or synthesis of a particular molecule. If both anabolism and catabolism used the same pathway, the cell would not be able control the rate of either process independent of the other: slowing the rate of catabolism would slow the rate of anabolism.

Opposite anabolic and catabolic pathways can occur in different parts of the same cell. For example, in the liver the breakdown of fatty acids to the molecule acetyl-CoA takes place inside mitochondria. Mitochondria are the tiny, membrane-bound organelles that function as the cell's major site of ATP production. The buildup of fatty acids from acetyl-CoA occurs in the cytosol of the cell, that is, in the aqueous area of the cell that contains various solutes.

Although anabolic and catabolic pathways are controlled independently, both metabolic routes share an important common sequence of reactions that is known collectively as the citric acid cycle, or Krebs cycle. The Krebs cycle is part of a larger series of enzymatic reactions collectively called oxidative phosphorylation. This pathway is an important means of breaking down glucose to produce energy, which is stored in the form of ATP. But the molecules produced by the Krebs cycle can also be used as precursor molecules, or raw materials, for anabolic reactions that make proteins, fats, and carbohydrates.

Despite the independence of anabolism and catabolism, the various steps of these processes are in some ways so intimately linked that they form what might be considered an "enzymatic ecological system." In this system, a change in one part of a metabolic series of reactions can have a ripple effect throughout the linked anabolic and catabolic pathways.

This ripple effect is the cell's way of counterbalancing an increase or decrease in anabolism of a molecule with an opposite increase or decrease in catabolism. This lets the cell adjust the rate of anabolic and catabolic reactions to meet its immediate needs, and prevent imbalance of either anabolic or catabolic products.

For example, when the cell needs to produce specific proteins, it produces only enough of each of the various amino acids needed to synthesize those proteins. Moreover, certain amino acids are used by the cell to make glucose, which appears in the blood, or glycogen, a carbohydrate stored in the liver. So the products of amino acid catabolism do not accumulate, but rather feed the anabolic pathways of carbohydrate synthesis. Thus, while many organisms store energy-rich nutrients such as carbohydrates and fat, most do not store other biomolecules, such as proteins, or nucleic acids, the building blocks of deoxyribonucleic acid (DNA).

The cell regulates the rate of anabolic reactions by means of allosteric enzymes. The activity of these enzymes increases or decreases in response to the presence or absence of the end product of the series of reactions. For example, if an anabolic series of reactions produces a particular amino acid, that amino acid inhibits the action of the allosteric enzyme, reducing the synthesis of that amino acid.

User Comments

Your email address will be altered so spam harvesting bots can't read it easily.
Hide my email completely instead?

Cancel or

Vote down Vote up

about 9 years ago

simplified version..thanks! =)

Vote down Vote up

over 8 years ago

Wow!!! I have a really big biology test coming up and this really helped me understand everything so much better.

Vote down Vote up

over 9 years ago

so helpful!!!!!!!!!!!!!!!

i dont normally write comments but i just had to this time..thanks;)

Vote down Vote up

almost 9 years ago

thanx=) helped me a whole lot on my lap report!

Vote down Vote up

almost 9 years ago

A great help with my bio homework! I thank you so much!

Vote down Vote up

almost 6 years ago


Vote down Vote up

about 4 years ago

very useful... and very nice

Vote down Vote up

over 5 years ago

thanks this was such a life saver i hate science with the passion but had a unit on it for health and social care

Vote down Vote up

over 5 years ago

thanks this was such a life saver i hate science with the passion but had a unit on it for health and social care

Vote down Vote up

over 8 years ago

Thanks a lot! Helped me understand better! I'm taking Micro this semester and it's hard stuff! Wish I had more help in understanding!!

Vote down Vote up

over 8 years ago

OMG...thank you soo much...its been very helpful in my biolgy assignment...LIFE SAVER =]


Vote down Vote up

over 8 years ago

Thank you for providing such resourceful topics, may God bless.

Vote down Vote up

over 4 years ago

I started my very first class of Biology today, and I must say that just by reading this article, I have learned a lot! Thank you for making my new Biology class "so interesting" already...Keep up the good work and God bless you and your knowledge.


Vote down Vote up

over 5 years ago

i got all the i

Vote down Vote up

almost 6 years ago

OMG shawty

Vote down Vote up

over 8 years ago

very useful...tnx

Vote down Vote up

over 8 years ago

kudos to u.ur material hhas been so helpful in my biochem assignment.thanx and keep it up.

Vote down Vote up

over 1 year ago

mcm backpack,http://www.mcm-bags.in.net/

mcm bags,http://www.mcmhandbags.com.co/

michael kors sale,http://www.michaelkors.so/

michael kors,http://www.michael--kors.us.com/

michael kors handbags,http://www.michaelkorsbags.us.org/

michael kors bags,http://www.michaelkorshandbags.org.uk/

michael kors outlet online,http://www.michael-kors-handbags.us.com/

coach usa,http://www.coach-handbags.com.co/

coach outlet store online,http://www.coachoutlet-online.com.co/

coach clearance,http://www.coachoutletstore.net.co/

coach outlet store,http://www.coachoutletstore-online.com.co/

coco chanel,http://www.coco-chanelbags.com.co/


gucci handbags,http://www.designerhandbagsoutlet.com.co/

sunglasses for women,http://www.eyeglassesonline.us.org/

cheap eyeglasses,http://www.eyeglassframes.us.org/

calvin klein clothes,http://www.fashion-clothing.us.org/

salvatore ferragamo,http://www.ferragamo.com.co/

ferragamo shoes,http://www.ferragamoshoes.net/

air huarache,http://www.air-huarache.co.uk/

air jordan retro,http://www.airjordans.us/

retro jordans,http://www.airjordanshoes2015.com/

nike air max,http://www.airmax-2015.org/

nike air max 2014,http://www.airmax-90.org/


cheap basketball shoes,http://www.basketballshoes.com.co/

beats by dre sale,http://www.beatsbydrdre.co.com/

beats by dr dre,http://www.beatsbydre.com.co/

monster beats outlet,http://www.beats-by-dre.com.co/

beats audio,http://www.beats-headphone.in.net/

bottega veneta,http://www.bottega.us/



burberry sale,http://www.burberryoutlet.me.uk/

burberry outlet online,http://www.burberryoutlet.club/

burberry handbags,http://www.burberrys-outletonline.in.net/

cheap calvin kleins,http://www.calvinklein.co.com/

celine bags,http://www.celinebags.org/

chanel handbags,http://www.chanelhandbags.net.in/

baseball bats,http://www.cheap-baseballbats.net/

louboutin shoes,http://www.christianlouboutinshoes.ar.com/

nba jerseys,http://www.cheap-jerseys.us.org/

air jordan,http://www.cheap-jordans.net/


nike outlet store,http://www.cheap-nike-shoes.net/

oakley outlet,http://www.cheapoakley.us.org/


insanity workout,http://www.insanityworkout.net.co/

iphone 5s cases,http://www.iphone-cases.com.co/

jimmy choo,http://www.jimmychoo.net.co/

air jordan retro,http://www.jordanretro.org/

jordan retro,http://www.jordan-shoes.com.co/

juicy couture outlet,http://www.juicycouture.com.co/

mont blanc pens,http://www.montblanc--pens.in.net/

new balance store,http://www.newbalance-outlet.org/

air max 2014,http://www.nike-air-max.us/

nike shoes,http://www.nikefactory.org/

free running,http://www.nikefree5.net/

nike running shoes,http://www.nikefree-run.net/

nike free run,http://www.nikefree-run.org.uk/

air jordan shoes,http://www.jordanrelease-dates.net/

soccer shoes,http://www.nikemercurial.in.net/

nike roshe run,http://www.nikerosherun.us/

nike outlet,http://www.nikestore.us/

north face backpacks,http://www.northface.us.org/

north clearance,http://www.northfaceoutlet.com.co/

cheap oakley sunglasses,http://www.oakleyoutlet.us.org/

oakley sunglasses,http://www.oakleysunglasses.gr.com/

oakley outlet,http://www.oakleysunglassescheap.in.net/

oakley vault,http://www.oakley-sunglasses.top/

rolex watches for sale,http://www.omegawatches.us.com/

pandora rings,http://www.pandora-charms.org.uk/

pandora jewelry,http://www.pandorajewelry.top/

ralph lauren outlet online,http://www.polo-outlets.com.co/

prada shoes,http://www.pradahandbags.net.co/

burberry handbags,http://burberry.outletnow.org/

louboutin shoes,http://christianlouboutin.outlet-shoes.net/

tory burch shoes,http://toryburch.salesandals.net/


abercrombie kids,http://www.abercrombiefitch.us.com/

abercrombie fitch,http://www.abercrombie-kids.us.com/

juicy couture handbags,http://www.juicycoutureoutlet.net.co/

kate spade handbags,http://www.kate-spade.net.co/

kate spade,http://www.katespade-outlet.net.co/

kate spade,http://www.kate-spade.in.net/

long champ,http://www.longchamp.us.org/

longchamp handbags,http://www.longchamp.com.co/

red bottom shoes,http://www.louboutin.jp.net/

louis vuitton,http://www.louis-vuittoncanada.ca/

louis vuitton outlet online,http://www.louisvuitton.jp.net/

louis vuitton uk,http://www.louis--vuitton.org.uk/

louis vuitton purses,http://www.louisvuitton.so/

louis vuitton outlet stores,http://www.louisvuittonas.com/

louis vuitton outlet online,http://www.louisvuitton-outlet.com.co/

louis vuitton outlet stores,http://www.louisvuitton-outlets.us/

marc by marc jacobs,http://www.marcjacobsonsale.com/


gucci shoes,http://www.gucci-uk.me.uk/

gucci shoes,http://www.guccihandbags.net.co/

gucci outlet,http://www.gucci-outletsale.in.net/

gucci shoes,http://www.gucci-outlet.biz/

gucci outlet,http://www.guccishoes.in.net/

gucci shoes,http://www.guccishoes.us.org/

hermes bags,http://www.hermesbags.club/

hermes bags,http://www.hermesbirkin.biz/

hermes birkin,http://www.hermesoutlet.top/

hollister clothing,http://www.hollister.us.org/


prada handbags,http://www.pradahandbags.com.co/

prada outlet,http://www.pradashoes.com.co/

polo ralph lauren,http://www.ralph-lauren.org.uk/

polo ralph lauren outlet,http://www.ralphlaurenoutlet.us.com/

ralph lauren uk,http://www.ralph-lauren-outlet.org.uk/

polo ralph lauren outlet,http://www.ralphlaurenoutletonline.com.co/

ralph lauren outlet,http://www.ralphlaurenoutletonline.in.net/

polo outlet online,http://www.ralphlaurenpolos.in.net/

ray ban outlet,http://www.ray-ban-outlet.us.com/

ray ban sunglasses,http://www.raybans.us.org/

ray bans,http://www.rayban-sunglasses.org.uk/

ray-ban sunglasses,http://www.rayban-sunglasses.us.org/

ray ban outlet,http://www.ray-ban-sunglasses-outlet.in.net/

ray ban outlet,http://www.raybanwayfarer.in.net/

replica louis vuitton,http://www.replicahandbags.com.co/

rolex watches for sale,http://www.replica-watches.us.com/

jordan 11,http://www.retro-jordans.com/

replica watches,http://www.rolex-watches.me.uk/

nike roshe,http://www.rosherun.org.uk/

nike roshe,http://www.rosheruns.us/

ferragamo outlet,http://www.salvatoreferragamo.in.net/

indoor soccer shoes,http://www.soccer-shoes.org/

baseball bats,http://www.softballbats.in.net/

supra footwear,http://www.suprashoes.in.net/

swarovski crystal,http://www.swarovskicrystal.com.co/

swarovski crystals,http://www.swarovskijewelry.com.co/

swarovski uk,http://www.swarovski-uk.org.uk/

north face outlet,http://www.the-northface.com.co/

north face jackets,http://www.the-northface.us.org/

the north face,http://www.thenorth-face.org.uk/

north face outlet,http://www.thenorthface.us.org/

north face outlet,http://www.thenorthfacejackets.in.net/

thomas sabo uk,http://www.thomas-sabo.me.uk/

tiffany and co,http://www.tiffanyandco.net.co/

tiffany jewelry,http://www.tiffanyjewelry.us.org/

timberland outlet,http://www.timberlandboots-outlet.in.net/

timberland shoes,http://www.timberlandshoes.com.co/

tommy hilfiger bags,http://www.tommyhilfiger.net.co/

tommy hilfiger bags,http://www.tommy-hilfigeroutlet.com/

toms shoes outlet,http://www.toms-shoes-outlet.net/

toms shoes outlet,http://www.toms-outletsale.in.net/

tom's shoes,http://www.toms-shoes.com.co/

tory burch shoes,http://www.tory-burch-outlet.in.net/

tory burch shoes,http://www.tory-burchoutlet.us.com/

true religion jeans,http://www.true-religion.com.co/

true religion,http://www.truereligionjeans.net.co/

true religion jeans outlet,http://www.truereligion-outlet.com.co/


ugg australia,http://www.uggboots.net.co/


ugg boots clearance,http://www.uggsonsale.com.co/

uggs on sale,http://www.uggsoutlet.com.co/

michael kors outlet online,http://www.michaelkorsoutlet.ar.com/

michael kors purses,http://www.michael-kors-outlet.us.org/

michael kors clearance,http://www.michaelkorsoutlet-online.ar.com/

michael kors outlet online sale,http://www.michael-kors-outlet-online.us.org/

michael kors outlet store,http://www.michaelkorsoutletonline-sale.us.com/

michael kors outlet,http://www.michaelkors-uk.org.uk/

oakley vault,http://www.cheap-oakleysunglasses.in.net/

ray ban sunglasses outlet,http://www.cheaprayban.com.co/

cheap shoes,http://www.cheapshoes.com.co/

uggs on sale,http://www.cheap-uggboots.in.net/

flat iron,http://www.chiflatiron.net.co/

christian louboutin,http://www.christian--louboutin.in.net/


louboutin shoes,http://www.christianlouboutinshoes.jp.net/

coach outlet store,http://www.coachfactory-outlet.co.com/

coach factory online,http://www.coachfactory-outlet-online.in.net/

coach outlet store,http://www.uptocoachoutlet.com/

vans outlet,http://www.vans-shoes.net/

wedding dress,http://www.weddingdressesuk.org.uk/

lululemon outlet,http://www.yogapants.com.co/

cheap ugg boots,http://www.ugg-boots.us.org/

ralph lauren outlet online,http://www.poloralphlaurenoutlet.net.co/

burberry handbags,http://www.burberryoutletonline.ar.com/

toms outlet,http://www.toms-outlet.net.co/

michael kors outlet online,http://www.michaelkors.in.net/

christian louboutin shoes,http://www.christianlouboutinoutlet.net.co/

tory burch handbags,http://www.toryburchsale.com.co/

prada handbags,http://www.pradaoutlet.com.co/

longchamp handbags,http://www.longchamp-handbags.in.net/


chanel outlet,http://www.chanel-bags.com.co/

true religion,http://www.truereligion-outlet.us.org/

abercrombie kids,http://www.abercrombie-and-fitch.us.com/

hollister kids,http://www.hollisterclothing.in.net/

new balance shoes,http://www.newbalance-shoes.org/

converse outlet,http://www.converses-shoes.net/


nfl jerseys,http://www.nfl-jersey.in.net/

cheap jerseys,http://www.cheapjerseys.us.org/

rolex watches for sale,http://www.rolex-watches.us.com/

replica watches,http://www.rolexwatchesforsale.us.com/


giuseppe zanotti,http://www.giuseppezanotti.com.co/



mizuno running shoes,http://www.mizunorunning.net/

wholesale handbags,http://www.handbagsoutlet.com.co/

tommy hilfiger outlet stores,http://www.hilfigeroutlet.in.net/

ed hardy clothing,http://www.edhardy.in.net/

levis outlet store,http://www.levisjeans.com.co/

bcbg max,http://www.bcbgdresses.net/

bebe clothing,http://www.bebeclothing.net/

harrods london,http://www.harrods-london.co.uk/

gucci shoes,http://www.guccishoes.com.co/

polo ralph lauren outlet,http://www.ralphlaurenoutletonline.us.org/


yoga pants,http://www.yoga-pants.ca/

nike outlet,http://www.nike-shoes-canada.ca/

pandora jewelry,http://www.pandora-charms-canada.ca/

rolex watches canada,http://www.rolex-watches-canada.ca/

michael kors outlet online,http://www.michael-kors-canada-outlet.ca/


tiffany and co,http://www.tiffanyandco-canada.ca/

hollister canada,http://www.hollistercanada.ca/



prom dresses,http://www.wedding--dresses.ca/

swarovski canada,http://www.swarovskicanada.ca/

tommy hilfiger outlet,http://www.tommy-hilfiger-canada.ca/

new balance shoes,http://www.new-balance.ca/

burberry canada,http://www.burberrycanada.ca/

north face canada,http://www.the-north-face.ca/

polo ralph lauren,http://www.ralph-lauren.ca/

ray ban,http://www.ray--ban.ca/

christian louboutin,http://www.christian-louboutin-shoes.ca/

nike air max,http://www.nike-air-max.ca/

bcbg max,http://www.bcbg-max-azria.ca/


Vote down Vote up

over 5 years ago

Thanx dude man if you were a women i would stay with for as long as i live

Vote down Vote up

about 1 month ago

Hi, I would like to cite your information for a biology paper that I have due soon. I would like to use your name and the date you wrote this information. I hope to receive this information from you at your earliest convenience. Thank you for the wonderful information. Awesome Job!

Vote down Vote up

2 months ago


Vote down Vote up

8 months ago

Awesome blog. I enjoyed reading your articles. This is truly a great read for me

Vote down Vote up

over 1 year ago

simple and straight forward, this has really made a great positive effect in my understanding of this topic,, thanx

Vote down Vote up

over 1 year ago


Vote down Vote up

almost 2 years ago

thank you

Vote down Vote up

almost 2 years ago

This is really great! very helpful.

Vote down Vote up

about 2 years ago

explicit, well explained

Vote down Vote up

about 2 years ago

I am confused of how catabolic and anabolisms are unified and helpful to learn biochemistry. Now, I am clear of it how these are helpful to learn biochemistry and their similarity and difference

Vote down Vote up

about 3 years ago

Well written text, thank you....

Vote down Vote up

almost 5 years ago

Great article. I love this websites text-speech feature. It really helps me absorb because I learn better when listening. I wish more informative websites had this feature.