How many calories in an Apple Pie?


Of course, there are many different apple pies, and many different serving portions  too!!!

So…let’s do the calculations with a “standar” apple pie…certainly not the best but it is standard, so standard that it is the same all around the world!

Of course, I am talking about the MacDonald Apple pie!

Nutrition facts of the Macdonald baked Apple pie (taken from the label):

Proteins 2g

Fat 13 g

Carbohydrates 32 g

Sodium 170 mg

How many calories are obtained when you eat 1 serving size of this pie?

Glycoconjugates and Membrane Carbohydrates


Cells recognize one another because of the saccharides attached to cell surfaces. 

They  are present usually as oligosaccharides associated through covalent links to lipids and/or proteins forming Glycoconjugates. The lipid or protein part is integrated into the cell membrane structure, with the saccharide part towards the external membrane surface.

Membrane carbohydrates  (2-10% of the membranes) are on the extracellular surface bounded to lipids or proteins of the membrane, forming glycoconjugates that serve as docking sites in cell recognition, adhesion and receptor action. These sugars include mainly glucose, galactose, mannose, fucose, N-acetyl galactosamine and  N-acetyl glucosamine.

The different kinds of Glycoconjugates include:

Proteoglycans: In the Proteoglycans, the Glucosaminoglycan moety forms the greater fraction of the molecule (tipically a proteoglycan consists of 95 % of carbohydrates) and is the main site of biological activity, providing multiple binding sites. They are found mainly in the extracellular matrix. They are major components of connective tissue.

Glycoproteins: Membrane bound glycoproteins participate in a wide range of cellular phenomena, including cell recognition, cell surface antigenicity, etc. In the glycoproteins, the majority of the molecule consist of proteins; they have one or more oligosaccharides attached to a protein, and they usually are branched and do not have serial repeats, so they are rich in information, forming highly specific sites for recognition and high affinity binding by other proteins

Glycolipids: are membrane lipids in which the hydrophilic head groups are oligosaccharides.

 As in glycoproteins, glycolipids  act as specific sites for recognition by carbohydrate binding proteins.  The four types of human RBC have different oligosaccharides (antigens) in their cell membranes. Blood groups depends on the gangliosides (a kind of sphingolipid) in the surface of the RBC .

About Tea and Toasts


A 70 year-old English lady that lives alone is admitted to the hospital for evaluation of a leg wound that is not healing properly. The patient also complains of pain in muscle and bones. On the examination, you find some hemorrhagic lesions in the skin, including ecchymosis in buttocks and both legs and petechiaes in other areas of the skin. The nails show splinter hemorrhages. When asked about her dietetic habits, the patient refers that she is too old to eat so much, so she has a very frugal lunch and dinners based mainly in tea and toasts.

Laboratory examinations show normal blood coagulation tests and Hemoglobin of 9.8 g/dL


The treatment for the condition described above should consist mainly in the administration of the following vitamin:


a)     Ascorbic Acid

b)     Biotin

c)      Folic Acid

d)     Pantothenic acid

e)     Niacin

f)       Vitamin B1

g)     Vitamin B2

h)    Vitamin B6

i)       Vitamin B12

j)       Vitamin D

k)     Vitamin E

l)       Vitamin K

Biochemistry of Platelets: Overview

Platelets or thrombocytes are blood cells which participate in the coagulation of blood.


Source of platelets.


Platelets are formed from their precursors in the hematopoietic tissue. 


Platelets, like other blood cells, are formed from Hemocytoblast that under certain conditions, and mainly under the effects of thrombopoietin, may be converted in a megacarioblast. Megacaryoblast is transformed into Promegacariocyte, and this cell in Megakaryocyte.


During Megakaryocyte maturation process,   DNA replication continues, and the nucleus suffers many divisions, but the cell continue undivided. While this process is going on, a large amount of cytoplasm accumulates.


Platelets are formed by the development of demarcation membranes in the cytoplasm, with subsequent release of the formed fragments to the venous sinusoids of the marrow bone.


A Megakaryocyte can release thousands of platelets, leaving the parenchyma cell with virtually only the nucleus and residual cytoplasma.



General structure:


Platelets are very small (1 to 4 microns in diameter) and circulate between 4 and 10 days, as flattened disks without nucleus. Platelet membrane is very rich in phospholipids and contains various glycoproteins that perform a fundamental role in the reception and transduction of intracellular signals. The cytoplasm of platelets contains a microphylament system and an actin/myosin contractile structure, called thrombosthenin, which, when activated, modify the conformation of the membrane. The cytoplasm also contains microtubules, which together with the microfilaments form an internal cytoskeleton responsible for the platelets conformation, but at the same time flexible enough to allow the conformational changes that occur during the platelet activation.


Platelet cytoplasm contains also residual endoplasmic reticulum(forming the so-called dense tubular system), mitochondria, glycogen and three different types of granules: Alpha granules, dense granules and lysosomal granules, containing biologically active substances that are released during the coagulation process The energy for platelet processes (aggregation, secretion and others) derive from the aerobic metabolism  in the mitochondria and anaerobic glycolysis (recall that the cytoplasm contains glycogen granules)


Platelet receptors and granules are particularly interesting from the physiological and medical point of view, so they will be discussed in more detail in future posts.


Recommended articles:


Flaumenhaft, R. et al:

The actin cytoskeleton differentially regulates platelet (alpha)granule and dense granule secretions.


The Online Metabolic and Molecular Bases of Inhereted Diseases.

The inhereted disorders of platelets




Question (B-15): Flavoproteins in Krebs Cycle


In this representation of Krebs Cycle, each reaction, is marked with a number.

Select the two reactions that require the participation of Flavoproteins.


a)     1 and 3


b)     2 and 4


c)      3 and 5


d)     4 and 6


e)     5 and 7


f)       6 and 8

Bioenergetics Question B-14



This compound dissipates the electrochemical gradient between the intermembrane space and the mitochondrial matrix, consequently the electron transportation takes place but not the synthesis of ATP


a)     Antimycin B

b)     Carbon Monoxide

c)      Oligomycin

d)     Rotenone

e)     UCP



After Vincent genetic test:

Vincent: What about the interview?

Dr. Lamar: That was it.


Basically GATTACA  is a movie about a future where your DNA becomes your Curriculum Vitae.

What does “GATTACA” means?

In the movie, it is the name of the facility where the action occurs, and apparently, it was the better way that was found by the creators of the movie for arranging the four “bases”  in the DNA (Adenine, Guanine, Cytosine and Thymine) in such a way that it sounds like a name.

The title sequences highlight these letters that represent the nitrogen bases in the DNA:



GATTACA main message is:

“There is no gen for the human spirit”



For additional information about this movie, please visit the Moviecular Biology page.