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Biol 2061 Cell and Developmental Biology-CELLS

The topic for today is simple and you guessed right, CELLS…. you know those tiny organisms that that make up all living creatures well scientifically speaking. The organism that I am choosing is a mouse probably the most famous creature in the world of science for various experiments to test new inventions by scientists.

So now I would like to officially introduce myself I am a Red Blood Cell also known as Erythrocytes and I live in the circulatory system of a mouse I was originated from the marrow tissue. I am responsible for the transportation of

  • nourishment
  • electrolytes
  • hormones
  • vitamins
  • antibodies
  • heat
  • oxygen
  • carbon dioxide
  • waste matter

I work very hard to get my duties done but eventually on the 120th day from my birth I die and I am quickly replaced. I am very narrow a sort of disk-like shape and this is necessary in order to fit through narrow blood vessels to reach every part of the mouse’s body or any other organim in which I inhabit.

Well this is just a little preview on my life but I will be back soon to tell you a few more interesting facts.

 
 

the end or not

Hey guys well I’m here again for the last time I think I’m not sure but I would just like to say it was a blast creating this blog and blogging and all the stuff in the middle I truly enjoyed biol 1362 it was the most demanding course but that was a good thing because in the end I learnt a lot and I would like to thank my teacher Mr Matthew for sticking with his students all the way. I do hope I am here next semester and I have Mr Matthew again it will be fun and a great way of learning and experiencing new learning techniques.

All the best to my fellow classmates I hope you all study hard, pray and do great in finals and I wish the same for myself. Good luck this was fun and see you all soon bye!

Always remember:

Success is to be measured not so much by the position that one has reached in life as by the obstacles which he has overcome and always be yourself, express yourself, have faith in yourself, do not go out and look for a successful personality and duplicate it.

 
 

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Published Paper 2

Clinical use of amino acids as dietary supplement: pros and cons

Hi everyone I’m back again with my second published paper so I hope you guys like it and here is the link if you want to do further readings  http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3118002/

Schrödinger said that life could be based on the Laws of Physics. Lots of attempts were put forward to define life. However, most received criticism, but, there is general agreement on three characteristics for all living systems self-reproduction, mutation and metabolism. Amino acids (AA) are very vital to life and they have been around for a very long time and are extremely important for sustaining life especially in terms of metabolic reactions.

Skeletal muscles are a reservoir for AA and when you have a problem with the reservoir you have a yield depletion of AA. Therefore adequate nutrition is important for a well balanced body which should not be something new to you. However, with age AA concentration decreases simply because the body does not function well anymore and supplements are required to fill in the gaps.

Essential amino acids (EAA) are those that must be supplied by your diet. EAA availability manages the balance between synthesis and degradation of human muscle, therefore, EAA availability is the restraining factor for preserving synthesis of new proteins. The ratio between degradation and synthesis is fundamental for maintaining efficient protein-based activities and functions and changing the magnitude of AA supply alters this balance. AA concentration in human cells is regulated by the expression of AA transporters, which are controlled and regulated with increasing EAA availability. Availability of all the EAAs in adequate stoichiometric ratios is not the only limiting factor for protein synthesis, but EAAs are also signaling molecules and gene expression modulators.

In humans, various studies have shown that EAAs are efficient in promoting protein synthesis independent of age and in reducing muscular catabolism even in prolonged bed rest in the elderly. Calculation of nitrogen balance provides the gold standard for the valuation of matching nitrogen demand and supply. It is widely accepted to calculate nitrogen balance by using urea synthesis and analyzing the relationship between oral protein intake and urea excretion in the urine. EAA should be performed until genetic expression of glutamine synthetic pathway would be restored and adequate glutamine synthesis from EAA and intermediates of TCA would be achieved. EAAs are indispensable for the maintenance of life under normal and pathological conditions and genetic expression modifications induced by increasing supply of EAA suggest beneficial effects of chronically modifying the ratio with non-essential AAs.

Methionine and L-form are most toxic when it comes to amino acids other than that the true measure would be to observe when the various types of amino acids are administered to see what adverse effects if any takes place.

In conclusion it is safe to say that the majority of research done on amino acids gave most positives and fewer negatives. So guys it is coming closer to the end of the semester day by day I do hope you all read and learn as much as you can finals are just around the corner.

References:

Forbes EB, Voris L, Bratzler JW, Wainio W. The utilization of energy-producing nutrients and protein as affected by the plane of protein intake. J Nutr. 1938;15:285

Halac E., Jr Studies of protein reserves. The relation between protein intake and resistance to protein deprivation. Am J Clin Nutr. 1962;11:574–576

 

 
 

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Electron Transport Chain

The electron transport chain takes place in the inner mitochondrion membrane. It follows the citric acid cycle, where NADH and FADH2 are reduced. These coenzymes then enter the electron transport chain.

The first step is the transfer of high-energy electrons from NADH+H+ to FMN, the first carrier in the chain. From each glucose molecule, two NADH+2H+ are generated from glycolysis, two from the formation of acetyl-CoA, and six from the citric acid cycle. In this transfer, a hydride ion H passes to FMN, which then picks up an additional H+ from the surrounding aqueous medium. As a result, NADH+H+ are oxidized to NAD+, and FMN is reduced to FMNH2.

In the second step in the electron transport chain, FMNH2 passes electrons to several iron-sulfur centers and then to coenzyme Q, which picks up an additional H+ from the surrounding aqueous medium. As a result, FMNH2 is oxidized to FMN.

The next sequence in the transport chain involves cytochromes, iron-sulfur clusters, and copper atoms located between coenzyme Q and molecular oxygen. Electrons are passed successively from coenzyme Q to cytochrome b, to Fe-S, to cytochrome c1, to cytochrome c, to Cu, to cytochrome a, and finally to cytochrome a3. Each carrier in the chain is reduced as it picks up electrons and is oxidized as it gives up electrons. The last cytochrome, cytochrome a3, passes its electrons to one-half of a molecule of oxygen, which becomes negatively charged and then picks up 2H+ from the surrounding medium to form H2O. This is the only point in aerobic cellular respiration where O2 is consumed.
Note that FADH2, derived from the citric acid cycle, is another source of electrons. However, FADH2 adds its electrons to the electron transport chain at a lower energy level than does NADH+H+. Due to this, the electron transport chain produces about one-third less energy for ATP generation when FADH2 donates electrons as compared with NADH+H+.

The various electron transfers in the electron transport chain generate 32 to 34 ATP molecules from each molecule of glucose that is oxidized 28 or 30 from the 10 molecules of NADH+H+ and 2 from each of the 2 molecules of FADH2 (4 total). Thus, during aerobic respiration, 36 or 38 ATPs can be generated from one molecule of glucose. Note that two of those ATPs come from substrate-level phosphorylation in glycolysis and two come from substrate-level phosphorylation in the citric acid cycle.

Well there you have it etc make sure and learn it!

 

 
 

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The Kerbs Cycle

Hey people I’m back again missed me? Lolz well today I’m going to talk a bit about the citric acid cycle aka the TCA cycle aka the Kerbs cycle. Okay so all of you must have done a little research on glycolysis so this won’t be that difficult to learn.

In aerobic conditions the end product of glycolysis is pyruvic acid. The next step is the formation of acetyl coenzyme A (acetyl CoA) and this is the initiator of the citric acid cycle. In carbohydrate metabolism, acetyl CoA links glycolysis and the citric acid cycle. The citric acid cycle contains the final oxidation reactions, linked to the electron transport chain, which produces the majority of ATP in the body. Formation of acetyl CoA comes from carbohydrates, as well as metabolism of fatty acids and amino acids. The reactions of the citric acid cycle and the electron transport chain both occur in the mitochondria.

Now here is a little help for those of you who are confused:

Step 1: The acetic acid subunit of acetyl CoA is combined with oxaloacetate to form a molecule of citrate. The acetyl coenzyme A acts only as a transporter of acetic acid from one enzyme to another. After Step 1, the coenzyme is released by hydrolysis so that it may combine with another acetic acid molecule to begin the Krebs cycle again.

Step 2: The citric acid molecule undergoes an isomerization. A hydroxyl group and a hydrogen molecule are removed from the citrate structure in the form of water. The two carbons form a double bond until the water molecule is added back. Only now, the hydroxyl group and hydrogen molecule are reversed with respect to the original structure of the citrate molecule. Thus, isocitrate is formed.

Step 3: In this step, the isocitrate molecule is oxidized by a NAD molecule. The NAD molecule is reduced by the hydrogen atom and the hydroxyl group. The NAD binds with a hydrogen atom and carries off the other hydrogen atom leaving a carbonyl group. This structure is very unstable, so a molecule of CO2 is released creating alpha-ketoglutarate.

Step 4: In this step, coenzyme A, returns to oxidize the alpha-ketoglutarate molecule. A molecule of NAD is reduced again to form NADH and leaves with another hydrogen. This instability causes a carbonyl group to be released as carbon dioxide and a thioester bond is formed in its place between the former alpha-ketoglutarate and coenzyme A to create a molecule of succinyl-coenzyme A complex.

Step 5: A water molecule sheds its hydrogen atoms to coenzyme A. Then, a free-floating phosphate group displaces coenzyme A and forms a bond with the succinyl complex. The phosphate is then transferred to a molecule of GDP to produce an energy molecule of GTP. It leaves behind a molecule of succinate.

Step 6: In this step, succinate is oxidized by a molecule of FAD (Flavin adenine dinucleotide). The FAD removes two hydrogen atoms from the succinate and forces a double bond to form between the two carbon atoms, thus creating fumarate.

Step 7: An enzyme adds water to the fumarate molecule to form malate. The malate is created by adding one hydrogen atom to a carbon atom and then adding a hydroxyl group to a carbon next to a terminal carbonyl group.

Step 8: In this final step, the malate molecule is oxidized by a NAD molecule. The carbon that carried the hydroxyl group is now converted into a carbonyl group. The end product is oxaloacetate which then combines with acetyl-coenzyme A and begin the Krebs cycle all over again.

Well I know that was alot as usual but don’t worry the semester is almost over keep the faith and study, study, study.

 

 
 

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Published Paper 1

The role and requirements of digestible dietary carbohydrates in infants and toddlers

Hey guys I know it has been awhile but I’m back and I have a little fact about infants so cute here it goes.Digestible dietary carbohydrate is one of the main sources of energy, growth and development in infancy and childhood. Most of it comes from lactose, starch and sugar. It is important to note that intake must also be regulated due to its negative effects later on in life which includes diabetes, tooth decay, obesity etc.

Infant formula should mainly consist of lactose, maltose, sucrose, glucose, maltodextrins, glucose syrup or dried glucose syrup, precooked and gelatinised starch. Infant formula is important for infant weaning and this is where you have an introduction of an adult diet and withdrawal of mother’s milk.

Studies have been made based on age, gender and total carbohydrate intake and were done in order to establish the importance of digestible dietary carbohydrates for infants and toddlers. It was concluded that a child’s age and gender will determine the recommended digestible dietary carbohydrates intake for proper growth and development.

A little extra note to keep in mind is that lactose concentration differs in women and the final concentration is reached within a few days of childbirth and where the breast milk fails to fill in nutrients for the baby infant formula does that and vice versa.

As a child increases in age new ways of acquiring the carbohydrates and other vital nutrients are introduced but is also monitored so your child will be well balanced. Without carbohydrates in the child’s diet brain development is restricted and lack of energy is achieved and these are not good characteristics for a young child.

In conclusion it is important for an infant to receive adequate amounts of digestible dietary carbohydrates for proper growth and development and of course it must be digestible they are babies after all. So guys that’s all for now be back soon. If you think it was too short here is the link read some more it’s pretty interesting http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3390559/ happy reading!!!!!!!!!!

 

 

References:

Paul AA, Southgate DA. McCance and Widdowson’s ‘The composition of foods’: dietary fibre in egg, meat and fish dishes. J Hum Nutr. 1979;33:335–336.

Stephen AM, Sieber GM, Gerster YA, Morgan DR. Intake of carbohydrate and its components–international comparisons, trends over time, and effects of changing to low-fat diets. Am J Clin Nutr. 1995;62:851S–867S.

 
 

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Image

wordle on glycolysis

 
 

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