Monday, March 31, 2008

Brain .thoda bheja lagana................












Human brain consist of 10 billion neurons ,billion means one thousand million,and million is equivalent to 1o lakhs.




These neurons are again having 10,ooo connections or synapses. (one single neuron),therefore brain is so complex. Its having wiring that works like a computer but it has ability to learn ,sense of self being,Dendrite recieve inputs while axon give output.



In this sidewali;;;; Image you can see synapse ,It is a connection between two neurons,the distance between the synapse is 20 nm.Its very large na!!!
In this Image a neuron is preparing itself for communication i mean to say they have neurotransmitters for that purpose.
Brain learn by adding or deleting the connections between the neurons they also learn on the basis of experience.
One more thing when you give excuse for a break remember brain requires very ..very little amount o energy to work.
four peanuts will be sufficient to provide energy for this computer ....................

Wednesday, March 26, 2008

Some times you do not like reading your subject ,you want to close your books if your mood is not up to the mark.................. try to study some outside things related to your text in the free time or can we term it -Applied sciences.,(will be applied to your mind and to your scores.)

Today I was reading about nicotine replacing agent ,means that it is not harmaful to the body and taken as subsituent for smoking in a magzine.

Nicotine found in plants mimics the receptor found in the body .The brain becomes addict to the nictine because it releases dopamine .Dopamine is responsible for Mast-ram kind of behaviour in us.It makes us feel happy or dopamine causes feel good factor for us,so we become addicted to nicotine which releases dopamine.

Pfizer the largest drug selling company in the world launched champix (smoking sensation drug ) today in India.(we smoke a lot)

Miller Urey Experiment...........





THe experimental instruments....
Miller and stanley .... were students from university of chicago. They conducted a experiment resembling the earth's primordial(latin primordial means -starting.) atmosphere,the gases were introduced and organic compounds were produced with the help of electricity(resembling lightning)









Miller Urey experiment>>>>>>>

Earth was formed five billion years ago.The primitive atmosphere was reducing in nature consisting of gases such as methane,ammonia ,nitrogen,hydrogen and water.(You require reducing atmosphere for organic chemistry to take place means for the synthesis of organic molecules,you require What????

Yes...... reducing atmosphere. ,oxidizing atmosphere is neutral) The organic molecules were synthesized ..Out of 20 amino caids present 13 were synthesized in the experiment.









Tuesday, March 25, 2008

Good website for lifescience jobs.




Good website for lifescience jobs.;

www.pharmajobs.com,

you will be saved from unnecessary troble of filtering the jobs related to lifesciences on other job sites .

Monday, March 24, 2008

Inner mitochondrial membrane...............







Today I will write aboutr Inner mitochondrial membrane.
Mitochondria are powerhouse of a cell,they convert potential energy of the food into the Atp form. They are double membraned (pmt question),
Outer membrane is smooth but this membrane have complex formed by protiens.
Lets move to inner membrane............
YOu watch TV ..............if you have seen castrol advertize ,It comes like ...
crb plus ka vada engine ki umr jyada. Now this crb ........we will use to remember the enzyme present in mitochondrial membrane(inner)
C- for citric acid cycle.
R- enzymes for respiratory chain...
b-Beta oxidation of fatty acids.
remeber this for solving questions............. it means that you have crb enzymes present in the inner mitochondrail membrane..

Saturday, March 22, 2008





Dna is superb molecule it contains codes for the proteins but how do dna control expressing of different genes in different cells is still a Mystery.........

Thursday, March 20, 2008




























Look at image in details ,important topic for exams.


. Chromosome 21 is the smallest chromosome with 50 million
bases.Trisomy of ch-21 causes down syndrome or down's syndrome.

2nd image-- remember characters.





Today I will write about down syndrome. Trisomy of chromosome 21
Syndrome -means ,Signs+symptoms seen in a person ,showing the presence of a particular disease for eg if a person is in love he will show love signs and symptoms. so you can say frien
d........ you are having love syndrome... and difference between symptoms and sign ..symptom is for patient ,means patient can recognize it while sign is discovered by doctor.



Down Syndrome—

It is a genetic disorder taking place during early life. Plz tell how many chromosomes will a person with down syndrome have??45/47 gues


ans -47,normal no of chromosome is 46 but due to trisomy it will become 47.



This extra chromosome causes problem with the way brain and body develops.



Look at the head here ...The head is smaller than normal and abnormally shaped. can you spot on .........some difference in eyes?

yes.............>>> the eyes are rounded at the inner corners (see your eyes in the mirror) just joking...


Other symptoms are in the image above.........





Good website.

A link to a website to get free tutorials on physics,chemistry and biology'''''''''''''''''''''

www.rapidlearningcenter.com






I will be telling you ,some tips for remembring imp functns of cellular organelles. look at the pictures carefully.







Lysosomes- Waste disposal ----Imagine a servant for the cell to throw away its waste.










Mitochondria-Power House --- They are responsible for energy production. See the above Image ,outer membrane and cristae.



Rough Endoplasmic reticulum- It is Protein Construction zone. It is called rough because it is having ribosomes and ribosomes are protien factory .


Golgi apparatus/ Golgi bodies if pmt wants to confuse you –they can also say dictyosome.

I will tell you the trick, break the word, Golgi was the scientist and apparatus means-set of instruments to perform a specific task.Here the golgi complex have sacs to perform packing of lipids and proteins.

Tuesday, March 18, 2008



Sometimes biology is so exciting look at the simple cell ,It can put large factories to shame ,so many chemicals are synthesized out in it in such a controlled manner , in very small space think of it >>>>>>>>>.


The interior of the cell is like a fully packed , movie hall or a crowded road in your city.You Know!!! to study all the protiens in the cell , we have a separate field called Proteomics and to study metabolites inside the cell a new field called Metabolomics is emerging (It will be helpful in designing newer drugs)


A simple tip for your exam always remeber the words in biology and try to break them .(useful for theory and objective)


Example-Eukaryote ,chalo we will break it ( Eu - true,karyon-nucleus) your textbook also writes it but if we give attention to get the meaning of the words by breaking them ..........we will not have to break our head........... we can get good marks. Now nucleus is having membrane so co- relate it with eukaryotic cell,it will have membrane bound organelles inside it and this is main question for your puc exam. One more thing it is near about 10 times larger than chotu prokaryotic cell.





























The first image is of fern having spores
. 2nd one is of fungal spore
3rd is of pollen grain.

What is the difference between a pollengrain and spore?


Thoda socho!!!


*


*


*


If you read about fungi you must have heard that they have pollen no Yaar!!


they have spores.,,,,The spores are found in smaller organisms.They are part of life cycle of algae,fungi,protozoans and plants...Remeber spores are usually Haploid and are produced by meiosis..

On the other hand...........

Pollen grains are vehicles on which male gametes are sitting or you can say they are like strong bikes having male gametes on them.Sporopollenin a substance found in exine (outer wall of pollen grains) is very strong.


So the main difference is-
Polllens are created by flowers and higher plants while spores are created by lower entities remember algae,fungi etc.





























Monday, March 17, 2008

Today I am writing about lipitor----It belongs to statin class of drugs which help in lowering down the cholesterol level in the body.


LIPITOR…………….the largest selling drug in the world.

….

GENERIC NAME- ATORVASTATIN, marketed under the trade name lipitor is the member of the statin (cholesterol lowering drugs) class of drugs .It is an inhibitor of enzyme HMG-CoA reductase, responsible for production of cholesterol in the liver thus it reduces the cholesterol produced in the body and in turn it reduces the total amount of LDL cholesterol (low density lipoproteins –LDL, they transport cholesterol from tissue to the blood, therefore harmful for the body)

The drug is a competitive inhibitor of the enzyme. It is a synthetic lipid lowering agent ,HMG-CoA reductase converts 3-hydroxy -3-methylglutaryl-coenzyme A to mevalonate ,a precursor of sterols ,including cholesterol .Cholesterol in the liver are incorporated into LDL and are released into plasma for delivery to peripheral tissues.Higher cholesterol levels promote cardiovascular diseases.

Mevalonatepathway…… It is an important cellular metabolic pathway present in all higher eukaryotes and many bacteria. It is important for the production of dimethylallyl pyrophosphate (DMAPP) and isopentenyl pyrophosphate (IPP) that serve as the basis for the biosynthesis of molecules used in processes as diverse as protein prenylation, cell membrane maintenance, hormones, protein anchoring and N-glycosylation.

Several key enzymes can be activated through DNA transcriptional regulation on activation of SREBP (Sterol Regulatory Element-Binding Protein-1 and -2). This intracellular sensor detects low cholesterol levels and stimulates endogenous production by the HMG-CoA reductase pathway, as well as increasing lipoprotein uptake by up-regulating the LDL receptor. Regulation of this pathway is also achieved by controlling the rate of translation of the mRNA, degradation of reductase and phosphorylation.

STATINS-

The statins (or HMG-CoA reductase inhibitors) form a class of hypolipidemicagents, used as pharmaceutical agents to lower cholesterol levels in people with or at risk for cardiovascular disease. They lower cholesterol by inhibiting the enzyme HMG-CoA reductase, which is the rate-limiting enzyme of the mevalonate pathway of cholesterol synthesis. Inhibition of this enzyme in the liver stimulates LDL receptors, resulting in an increased clearance of low-density lipoprotein (LDL) from the bloodstream and a decrease in blood cholesterol levels. The first results can be seen after one week of use and the effect is maximal after four to six weeks.

ROUTE OF ADMINISTRATION – ORAL

DOSAGE FORM/STRENGTH-10, 20, 40, 80- mg, tablets

SIDE EFFECTS-

Rare cases of muscle problems and liver problems have been associated with the use of atorvastatin and other similar medicines.. These may be early symptoms of muscle or liver problems.. Alcohol and atorvastatin can both be damaging to the liver. Alcohol should be used only in moderation.

ECONOMICS-

Pfizer is the company holding the patent rights for the drug, earning huge profits from it, the drug is expected to hit $13 billion mark this year.

Ranbaxy lost the legal case to produce the generic version of the drug. The Pfizer holds the U.S, patent for the drug till 2010.

Latest update-

According to the recent studies it is visible that this class of the drugs is not as much effective as they are projected by the large Pharma companies. The statins reduce heart attack risks but they are having side effects…. which can’t be ignored. (Business week, The Economic times)



Have any question in mind that excites you,not able to get the answer to it in any of the textbooks or by your lecturers (with respect) ?

Contact us at arpitmaheshwari06@gmail.com,we will reply within 15 days....questions must be related to biochemistry ,.human biology,genetics,medicine no botany please.....

Very good online notes material.


Here are two websites from where you can get lots of free notes material.

1 opencourseware@mit.edu. 2 http://ocwconsortium.org/



Guess ???? What are they!

They are phytoplanktons now you will ask what are phytoplanktons,they are small microscopic plants obviuosly seen with the help of microscope (above image) found in oceans.

USE>>>>They have silica In their cell walls ,we use it in the chemistry labs as filtering agents.


Some important facts you will like to know...

The distance between two neurons is 20nm and they are joined together by adhesive protiens .This protiens do not allow the movement .
The only egg laying mammal is platypus.

Saturday, March 15, 2008





This question is very important ...it is in forefront of the heart related diseases worldwide..

Why do heart muscles do not repair ,contrast to other muscles of the body which can repair after an injury or accident?

This happens because the heart muscles have specialized cells called as cardiomyocytes-----we will break the word,cardio-heart,myo-muscles,cytes -cells.
This cells do not regenerate after an injury ,if scientist are able to find some method by using stem cells or any other process to solve this complex mechanism it will be amazing discovery to solve the heart related problems.

Friday, March 14, 2008

Biology is interesting,the way it is taught in our school is so boring if indian students follow some points return below..... the subject can be very interesting-

Ask doubts to your teachers.
Search the articles on the internet.
Read science magzines ,the way any research associate explains his work is totally different from your school teacher.
Internet images options is also present ,having the options for large ,medium and smaller size images.

I will write more in this one month vacation time ,,,,,,keep reading