Saturated fats vs. Unsaturated fats

SATURATED FATS

  • consists of single bonds
  • high melting pt
  • solid @ room temp
  • can be found in Butter, coconut oil, whole milk, meat,peanut butter,margarine,cheese,vegetable oil or fish oil
  • Excessive consumption is not good because of their association with atherosclerosis and heart diseases.
  • Saturated fats increase LDL (bad cholesterol) and decrease the HDL

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UNSATURATED FATS

  • consists of atleast 1 double bond
  • low melting pt
  • liquid at room temp
  • can be found in Avocado, soybean oil, canola oil and olive oil
  • Unsaturated fats are considered good to eat if you are watching your cholesterol.
  • Unsaturated fats increase high-density lipoprotein ( HDL or good cholesterol) and decrease LDL (bad cholesterol)

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Krebs Cycle Song

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TCA aka Krebs Cycle

  • TCA/Krebs cycle occurs in the mitochondria
  • it is the final pathway where oxidative metabolism of cards, amino acids and fatty acids converge
  • provides energy for the production of ATP
  • Glycolysis produces pyruvate which is converted to acetyl CoA by pyruvate dehydrogenase complex

Pathway

  1. Condensation of acetyl CoA and oxaloacetate to form citrate it is catalyzed by citrate synthase.  Substrate availability is a key means of regulation for citrate synthase. Binding of oxaloacetate causes a conformational change in the enzyme that generates a binding site for acetyl CoA.
  2. Rate-limiting step! Citrate is isomerized to isocitrate by aconitase, a Fe-S protein.
  3. Isocitrate dehydrogenase catalyzes the irreversible oxidative decarboxylation of isocitrate, yielding 3 NADH molecules produced by the cycle, and releases CO2. This is one of the rate limiting steps of the cycle. It is allsterically activated by ADP and Ca2+ and is inhibited by ATP and NADH.
  4.  α-ketoglutarate dehydrogenase complex catalyzes the conversion of  α-ketoglutarate to succinyl CoA. There is a release of the 2nd CO2 and produces the 2nd NADH of the cycle.
  5. Succinate thiokinase cleaves the high-energy thioester bond of succinyl CoA. The rxn is coupled to phosphorylation of guanosine diphosphate to guanosine triphosphate. GTP and ATP are energetically interconvertible by the nucleoside diphosphate kinase rxn.
  6. Succinate dehydrogenase is embedded in the inner mitochondrial membrane and it functions as complex II of ETC. succinate is oxidized to fumarate by succinate dehydrogenase, producing the reduced coenzyme FADH2 .
  7. Fumarase catalyses the hydration of fumarate to malate
  8. Maltate dehydrogenase oxidizes malate to oxaloacetate. This leads to the production of the third and final NADH (yields approx. 3 ATP)

 

ATP_Wizard_by_FreakyPeep

Bird flu (research paper take 2)

BIRD FLU

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H5N1 virus is a new strain of bird flu. However it is not airborne. There are new developments which can lead to vaccines to prevent new strains of bird flu so it would not be able to infect humans in any which way. In order for the virus for the virus not to be transmitted between human to human there can be restriction in the replication process of the H5N1 virus.

However it is uncommon for the virus to infect humans. This is due to the difference in the receptors in human’s noses and that of a bird. Researchers did find that mutations of the virus can infect ferrets which can lead to infection in other animals.

Now researchers are trying to understand how the virus mutates in natural conditions in order to prepare for pandemic in humans.

bird_flu_and_giant_asteroid_by_andycouncil

Just 2 questions…

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1)      Which steps of glycolysis is ATP produced?

I.  step  7      II.  Step 3   III.  Step 1    IV. Step 5    V.  step 10  

       A)  I. & V.

       B) III. & II.

       C)I. & IV.

        D) III.  &  V.

 

 

2)      What class of enzymes catalyze the reaction in which two compounds linked with breaking of phosphate bond in ATP of any similar compound providing energy?

A) Isomerase

B) Oxidoreductase

C) Lagase

D) Hydrolyses

MDMA (research paper take 1)

MDMA

MDMA is known as the drug “ecstasy” but recently a purer form of MDMA was produced which was rebranded as “Molly”. MDMA (3,4-methylenedioxymethamphetamine) can be seen being used at raves and nightclubs. However,  MDMA can affect both the brain and the body.

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When MDMA is taken orally it affects the amount of serotonin, dopamine and norepinephrine released. Serotonin disturbs one’s eating habits, rest and can definitely alter a person’s mood it also causes the release of vasopressin and oxytocin. The hormones oxytocin and vasopressin are both responsible for the feelings experienced by MDMA which can be described as a sense of euphoria. Serotonin is important to brain but a rush of it can lead to the lessening of the chemical when it is much needed which causes the person to go into a downward spiral of emotions. This can lead to addiction or experimentation of a mixture of drugs just to achieve that euphoria once again.

MDMA not only affects the brain but can physically affect the body. It can cause increased heart rate and hyperthermia which can lead to stoppage of the heart, liver or kidney. It can also tamper with its on metabolism which can lead to a dangerous amount of MDMA in the body. Addicts who willingly or unwillingly experiment with the mixture of different drugs with MDMA fall prey to higher risk of health problems. MDMA can indirectly be one of the causes of an increase of STD’s and HIV. It can lead users to indulge in unprotected sex which can spread be spread to anyone.

MDMA is dangerous when it the person experimenting for the first time becomes an abuser of the drug. However  it has therapeutic value and can be helpful to someone in need once the doses are monitored.

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Drugabuse.gov. “MDMA (Ecstasy) | National Institute on Drug Abuse.” 2012. http://www.drugabuse.gov/publications/drugfacts/mdma-ecstasy (accessed 11 Apr 2013).

Glycolysis: Fates of Pyruvate

Glycolysis: Fates of Pyruvate

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