1)__________ are macromolecules that are made up of repeated molecules of glucose.

2)At physiological pH, amino acids are zwitterions. Which of the following is a zwitterion?

A. A
B. B
C. C
D. D

3)

Collagen, a major component of skin and bone, is a fibrous protein with repeating units of Pro-Gly-X or Hyp-Gly-X. Collagen has strength because the structure is:

A.         Web like

B.         Three interlaced helices forming a rope

C.         An a-helix

D.         A b-sheet

E.         A b-barrel

4)

Proteins must fold into their final structures to be functional. Which of the following statements are not true?

A.         Protein tertiary structure is determined by the primary sequence.

B.         Hydrophobic amino acids are buried in the interior.

C.         Structural motifs such as aa or bb act as seeds around which the rest of the protein folds.

D.         Helper proteins called chaperones may assist protein folding.

E.         Folding begins with disulfide bond formation.

5)

Triacylglycerols are a cellular metabolic fuel. Which of the following are true of triacylglycerols?

A.            They are polar, hydrophobic molecules.

B.            Most triacylglycerols have three fatty acid groups that are identical.

C.            They should be completely eliminated from the human diet.

D.            Triacylglycerols from animals are solids at room temperature while those from plants are liquid.

some easy questions

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Lipids and membranes

This video focuses on the topic lipids and membranes . Its quite long 52 minutes all together . It starts off slowly by defining what are lipids

Lipids are non polar hydrophobic compounds that are soluble in organic solvents .most membrane lipids are amphiphatic having a polar and non polar end . it shows the various functions and types of lipids and fatty acids
Lipids are distinguished by their high solubility in non polar
solvents and low solubility in H2O
● Diverse group of compounds including Fats, Oils, Waxes, some
vitamins and hormones and most non-protein components of
membranes.
Lipids are amphipathic molecules that can be:
(A) Major components of biological membranes
● membranes define the basic unit of life (cell) and subcellular
compartments (eucaryotes)
● includes cholesterol
(B) Major form of stored energy in biological systems
● lipids are largely reduced compounds; complete oxidation of lipids
generates lots of energy
(C) Hormones
● signal transduction between cells

types of lipids :

Fatty acids: principal building
blocks of complex lipids

Waxes: esters of fatty acids
(heat sensitive)

Triacylglycerols: membrane
precursors, energy storage

Glycerophospholipids:
membrane components

Sphingolipids: brain lipids,
membrane components

Steroids: cholesterol, bile
salts, steroid hormones
Fatty acids : Composed of a carboxylic acid “head group” and a long hydrocarbon
“tail”
– tail generally contains an even number of carbon atoms
● Hydrocarbon tail can be saturated or unsaturated
– unsaturated hydrocarbon tails contain one or more double bonds

This video was very long and tedious and her accent was somewhat hard to understand . I din not enjoy watching this video . Although it covered the topic of lipids and membranes thoroughly i was not enthused to learn. compared to the other videos on youtube such as Mr.JM videos , i rather watch those as his voice is much more soothing and he doesn’t have an accent . He teaches much better and makes learning enjoyable and easy

ENZYMES

You will learn about the seven features common to all enzymes, and the four general classes of reactions that are governed by enzymes. The function of metabolism is explained and the role of light and the kinetic energy of moving molecules, as two principle sources of activation energy for reactions, is discussed.

woke up this morning sugar was on my mind!!! glycoysis video .

This video is a song version entitled woke up this morning sugar was on my mind . well that’s how it starts off . This video was so much fun and very entertaining . it made learning glycolysis fun . my friend and i stumbled upon it while searching up videos on you tube . And it quickly got my attention.
The song states that glycolysis starts off with glucose ,C6H12O6. and the process breaks it down with various enzymes “Ten separate reactions,
Ten separate enzymes,
In a cytoplasmic assembly line” He then goes on to explain the 10 steps of glycolysis and the various products formed or given off .Although 2 ATP molecules are used in steps 1-3, 2 ATP molecules are generated in step 7 and 2 more in step 10. This gives a total of 4 ATP molecules produced. If you subtract the 2 ATP molecules used in steps 1-3 from the 4 generated at the end of step 10, you end up with a net total of 2 ATP molecules produced.

these are the lyrics :
LYRICS

Woke up this morning, sugar was on my mind (her name is glucose)
Woke up this morning, sugar was on my mind
It’s time for my sugar’s breakdown,
It’s glycolysis time.

My sugar is so sweet,
She means so much to me,
But I’m prepared to give her up,
For a little ATP

Her chemical formula
C6H12O6
Glycolysis will break her down,
With enzymatic tricks

Ten separate reactions,
Ten separate enzymes,
In a cytoplasmic assembly line,
Cells do it all the time!

CHORUS

Glycolysis
Has 3 basic parts.
The 1st part’s activation,
So that’s where we’ll start

Enzymes take two phosphates from ATP,
And jam them onto glucose,
With through some rearrangements
Is now really a fructose

Fructose 1-6 diphosphate
Brimming with energy
About to fall apart
In the next step you will see,

CHORUS

Glycolysis’s name
Comes from its second part
When fructose 1-6 diphosphate
By enzymes is ripped apart.

Cause glycolysis means splitting sugar,
And this is really cool,
This cleavage results in two
three-carbon molecules

And when the next enzyme does its work
We’ll see that my sugar’s fate
Was to be made into two
Glyceraldehydes 3 phosphates
CHORUS
Glyceraldehyde 3 phosphate
Is known as G3P
And in step 3 of glycolysis
We harvest its energy

The harvest begins
With NAD+’s reduction
To NADH, which has
Electron carrying function.

Then enzymatic action,
Harvests more energy,
Which comes as the payoff
2 ATPs from each G3P

CHORUS

1 NADH, 2 ATPs
From every G3P
So the gross yield per glucose is 2 NADH
and 4 ATPs

But remember the 2ATPs
Invested in step 1
So the net yield is 2 ATPs
You can use to jump or run

So our overall net is
2 NADH and 2 ATPs
My sugar it was worth it,
Forgive me baby please.

CHORUS

When all was done, I looked at my sugar,
She didn’t look that great,
Two ATPs, two NADHs,
two three-carbon pyruvates

NADH is used in the last part
Of cellular respiration
It’s fuel to make ATP in
Oxidative phosphorylation

So when you look at your sugar.
Have some pity in your eyes
Glycolysis, getting energy,
Is based on your sugar’s demise!

research review 2

i chose to to do a review on this paper because it appealed to and intrigued me . last year summer i was working in the waterloo UTT research station .For the summer we did research on aniti cancer , antiherbal properties of various fruits and leaves etc . For the upcoming summer i will doing  research on two different varieties of soursop leaves and fruit samples and testing their bio active compounds , antioxidant concentration and possible antic-herbal properties . Bio sciences , agriculture and food technology intrigues me that is why i decided to review this paper hope u enjoyed it 🙂

second research paper review on soursop aka graviola and its anti-tumor properties

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SOURSOP (ANNONA MURICATA)  ANTICANCER AND  HERBAL PROPERTIES !

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Graviola: A novel promising natural-derived drug that inhibits tumorigenicity and metastasis of pancreatic cancer cells in vitro and in vivo through altering cell metabolism by :

María P. Torresa, b, Satyanarayana Rachagania, Vinee Purohitb, Poomy Pandeyc, Suhasini Joshia, Erik D. Moorea, Sonny L. Johanssonb, d, Pankaj K. Singha, b, Apar K. Gantie, Surinder K. Batraa, b, d, ,

a Department of Biochemistry and Molecular Biology, Omaha, NE 68198-5870, USA

b Eppley Institute for Research in Cancer and Allied Diseases, Omaha, NE 68198-5870, USA

c Department of Environmental, Agricultural & Occupational Health, Omaha, NE 68198-5870, USA

d Department of Pathology and Microbiology, Omaha, NE 68198-5870, USA

e Department of Internal Medicine VA Nebraska-Western Iowa Health Care System and University of Nebraska Medical Center, Omaha, NE 68198-5870, USA

 

The following is a review on a paper I read up on titled  : Graviola: A novel promising natural-derived drug that inhibits tumorigenicity and metastasis of pancreatic cancer cells in vitro and in vivo through altering cell metabolism. Various parts of the Graviola tree — including the bark, leaves, roots, fruit and fruit-seeds — have been used for centuries by medicine men and native Indians in South America to treat heart disease, asthma, liver problems and arthritis.

 In this paper  they show that  the Pancreatic tumors are resilient to  chemotherapies utilised in cancer normally for treatment . the aim of the study illustrated  research done to determine  the possibility  of a innovative plant-made product or substance that can be utilised  as a healing agent for pancreatic cancer .  in the study the direct   effects of an  Annona Muricata  (soursop ) also known as graviola , was assessed and tested  for the following :cytotoxicity, cell metabolism, cancer-associated protein/gene expression, tumorigenicity, and metastatic properties of the cancerous  cells.

Studies from 1998 to 2000 by McLaughlin and Chih HW, Chui HF have shown that acetogenins are inhibitors of complex I of oxidative phosphorylation chain thereby block the formation of ATP energy needed by the cancer cell to operate your pump P-glycoprotein mediated, allowing you to stay active. The acetogenins also inhibit the ubiquinone-ubiquinone oxidase, NADH-dependent enzyme that is peculiar to the plasma membrane of the cancer cell.

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On completion of the research data obtained form the experiments that the soursop (annona murciata )   promoted and subsequently caused necrosis of the pancreatic cancer cells by the process of cellular metabolism inhibition .

Their research Overall, the compounds that are naturally present in a Graviola extract inhibited multiple signaling pathways that regulate metabolism, cell cycle, survival, and metastatic properties in PC cells. Collectively, alterations in these parameters led to a decrease in tumorigenicity and metastasis of orthotopically implanted pancreatic tumors, indicating promising characteristics of the natural product against this lethal disease.

Their research illustrated that basically all the antioxidants and bioactive compounds that are present in the soursop fruit extract resulted in inhibition several signalling pathways that were responsible for regulating pathways for cell cycle metabolism , its continued existence  and also its ability to metastasize in the cancerous cells . Also changes in these specific parameters resulted in a significant decrease in the tumours  mestasizing or growing . Thus demonstrating  favourable characteristics of the annona muricata aka soursop against cancers .Image

Knowledge about  an increased consumption of fruits and vegetables is associated with a reduced risk of most cancers, including PC is popular and known worldwide   . The major bioactive components that have been extracted from different parts of the plant are known as Annonaceous acetogenins.

For the research conducted for the study a series of tests and experiments were conducted such as : testing the graviola extract first . the cytoxicity and antibodies were tested as well  . western blot analysis and real time PCR were used to test the samples . glucose uptake and ATP quantification and cell cycle ananlysis were done on the data . then In vivo tumorigenicity studies conducted on samples displayed positive results for soursops anticancer properties .

The research paper goes on to state that according to the obtained results  from in vitro experiments, upon statistical analysis the ‘ Graviola extract has promising properties to be incorporated in PC therapeutics.’  However, these anti-tumorigenic properties entail advance validation through in vivo experiments.Image

The present study is the first to demonstrate that Graviola extract reduces the viability of PC cells and tumors by inducing necrosis and cell cycle arrest, and by inhibiting PC cell motility (i.e. cytoskeleton rearrangement), migration, and metabolism. Overall, in vitro experiments revealed that the compounds present in the natural extract inhibited several pathways involved in PC cell proliferation and metabolism, simultaneously. Such inhibitions ultimately led to a decrease in tumor growth and metastasis in orthotopically transplanted pancreatic tumor-bearing mice

 

 

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They stated that their study was in fact the first of its like to show that soursop (graviola) extracts in fact decreases the pancreatic cancerous cells sustainability by the process of inducing cell cycle arrest and necrosis by the cancerous tumor cell motility inhibition .  they data show that  these inhibitions in the end steered to  tumor growth  decreasing and metastasis in orthotopically transplanted pancreatic tumor-bearing mice.

While necrotic agents have not been considered beneficial in cancer therapies due to induction of local inflammation, the process itself can lead to the activation of the innate immune system capable of initiating anti-tumor immunity  ( R.K. Amaravadi, C.B. Thompson)

The main bioactive compounds recognised in Annona  Muricata(soursop) have been classified as Annonaceous acetogenins, which  causes the inhibition of  mitochondrial complex I that consequently results in ATP production being decreased . Despite the fact that the extract capsules utilised in this research had many other compounds within it .The  Annonaceous acetogenins were clearly evident of being present  and illustrated a significant depletion of the ATP production in the pancreatic cancer cells upon being treated with the graviola extract

 

 

 

    Reference

 

  • The roles of therapy-induced autophagy and necrosis in cancer treatment by R.K. Amaravadi, C.B. Thompson.

LACTOSE INTOLERANCE PAPER REVIEW 1.

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LACTOSE INTOLERENCE

The following is a review on a paper I read up on titled  : “Systemic lactose intolerance: a new perspective on an old problem” by   S B Matthews, J P Waud, A G Roberts, A K Campbell.

 The body’s intolerance to various types of  foods can result in an range of  different gut and systemic symptoms.

The ability to determine that these has been as a result of lactose has been  overlooked and not recognised due to various food and drink  manufacturers  secretly adding lactose and refraining from labelling that it contains it . Thus causing a confusion with respect to diagnosis on dietary removal of the respective dairy foods .Image

Lactose Intolerance, commonly known as milk intolerance or dairy product intolerance, is an inability to digest lactose in small intestines. Lactose, a type of discharide sugar consisting of galactose bound to glucose, is commonly found in milk and other dairy products. The absorption necessitates the hydrolysis of lactose to it’s components by the enzyme lactase. This is the enzyme not present or the absorption does not occur correctly in those with lactose intolerance .

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 The cause Lactose intolerance is very common among people. The cause is the deficiency of lactase and it is because of both genetic and environmental induced factors. I myself suffer with this problem L  that is why this research paper was rather useful and informative to me . Not only did it apply to me on a personal level , but I aided me in understanding  the topic much better .

They also pointed out the significance  in being able to  differentiate between hypolactasia, a low level of lactase, and clinical lactose intolerance. (I had no idea about this )  It goes on to describe the mechanisms causing lactose intolerance , which is the unique enzyme called lactase . (this I knew already ). However  I did not know there were in fact   three causes of loss of lactase (hypolactasia) which are :

  • Congenital complete loss of lactase (very rare).
  • Inherited loss, after weaning (common).
  • Secondary intestinal damage, for example, infections such rotavirus and Giardia, or hormonal imbalance.

When lactose reaches bacteria in the hypoxic large intestine, hydrogen and other metabolites are generated.

 The condition Lactose intolerance was initially detailed and  described by Hippocrates. Despite  his recognition of this  long ago  it is only within  the last 50 years that  this condition been documented , acknowledged and diagnosed medically

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The paper also indicated that patients who suffer with lactose intolerance must also be advised of something they refer to as risk food .As a result of manufacturers inadequate labelling and negligence in mentioning the lactose in their products . Some examples of such food products are processed meats, bread, cake mixes, soft drinks, and lagers. This was very shocking to me  :o. I really and truly did not know this and I am pleased to have stumbled upon this research paper.  Therefore in the future I would be weary of what I eat , I now understand my frequent gas issues , flatulence and upset stomach .

On completion of reading this paper I was able to deduce that  lactose can cause a range of debilitating systemic symptoms, as well as  the renowned gut symptoms.

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Postgrad Med J 2005;81:167-173 doi:10.1136/pgmj.2004.025551

Systemic lactose intolerance: a new perspective on an old problem

S B Matthews1, J P Waud1, A G Roberts2, A K Campbell3

+ Author Affiliations

1Department of Medical Biochemistry and Immunology, Llandough Hospital, Cardiff and Vale NHS Trust, Penarth, Vale of Glamorgan, UK

2Department of Medical Biochemistry and Immunology, Cardiff and Vale NHS Trust, Cardiff, UK

3Department of Medical Biochemistry and Immunology, Wales College of Medicine, Cardiff University, Cardiff, UK

Correspondence to:
 Professor A K Campbell
 Department of Medical Biochemistry and Immunology, Wales College of Medicine, Cardiff University, Heath Park, Cardiff CF14 4XN, UK; campbellak@cf.ac.uk

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