Whales

All of us at least once we have read or have read the story of Pinocchio , the wooden puppet of Collodi's story , which is eaten by a whale , as did the unusual , not so much for the puppet who came to life , but what concerns what a whale can ingest . By now everyone knows that these whales feed on krill, very small animals that are captured through the baleen plates , which filter the water literally . With this blast from the past want to talk about whales, or rather of the order Cetacea , the two sub orders, Mysticeti and Odontoceti . In this post I dedicate myself to Mysticeti , what we all know as whales, but we take a step back , as we are talking about is of aquatic animals , but we must not forget that they are mammals.The history of evolution has taught us that life originated about 360 million years ago, in the Devonian , in an aquatic environment , and the earliest forms of fish evolved more slowly colonized terrestrial environments , thanks to their ability to capture the ' oxygen in the atmosphere. The terrestrial vertebrates colonized the land , and we are talking of the great dinosaurs, extinct, to one of the theories in vogue , because of a meteorite. After this catastrophic event survived only small rodents, with great adaptability, which gave birth to the largest group of mammals . One of them slowly " came " back to the aquatic environment . This led them to have more morphological changes in order to live in an aquatic environment , we are talking about Mesonychidae , animals like dogs , who were still adapted to the terrestrial environment . From this family we remember the kind of Mesonyx , which gave rise to an evolutionary line that led to Hippos and cows. About 50 million years ago developed the first organisms in the order of Archoceti , primitive cetaceans , which had significantly lower legs , while the front legs are modified into flippers , more suited to swimming, the compression of the skull. Since these forms of extinct have evolved Odontocetes ( eg dolphins ) and Baleen ( eg whales ) , which differ by the presence of the teeth in the first , and the nose, as in the second there are two breathers .
With Misticei mean those animals are commonly known as whale ch . Aristotle was the first to understand that they were mammals, many remember him now because they are marine mammals ! To date, we find two families , the first ones whales ( Balinopteridae ) , large animals , the greatest that ever lived on earth, so much so that a three year old child could walk into a his aorta , have a relatively reduced , in fact only go up to 150 tons , a dorsal fin not very big. Include the blue whale 

(Balenoptera musculus ) , minke whales 

(Balenoptera acutorostara ) the smallest , the humpback whale ( Megaptera Maegaptera ), the largest , the latter also famous because often it is found in the presence of bumps along the body , which limestone formations are made ​​by the parasites, the Barnacle . The humpback whale limbs are longer than the entire animal kingdom , in fact, their dorsal fins can reach a length of 5 meters. The second family is that of balenidi ( Balaenidae ) , small animals , aged between 12 and 18 meters , with more stubby shape , a maximum weight of 100 tons. Here we find the right whales ( Eubalaena glacialis and Eubalaena australis) , who live in the ' Atlantic Ocean and Pacific Ocean . Corneas have calluses on his head, too, are parasitized by parasites , crustaceans commonly called the " whale lice " . A characteristic of these the splendid animals is their ability to take advantage of the wind on the " swimming sailing " using their large tail as a sail. The Greenland whale ( Balaena mysticetus ) , which has the longest baleen of the whole family. Other members are the gray whale ( Eschricthius robustus ) , the Caperea ( Caperea marginata ) .

Thanks Margherita Hack

This post is all for a great woman, a single person who, with his intellect, his vivacity , his mental acuity has given very, very much to science , but not only , even ordinary people , not those of science ,. I'm talking about Margherita Hack, world-renowned astrophysicist , but also known for its secularism in Italy , his being always vegetarian , his being fond of animals , for civil rights , for his environmentalism ( he used the bike up to nearly ninety years of age)
Born June 12, 1922 , he lived his youth in Florence , then came the dark period of Italy, during the Fascist era , where he attended the gymnasium School and says she jumped maturity thanks to the war , then joined the faculty of letters before but the first lesson was bored and ran into the secretary to change course , he chose physics , matter who loved since high school . She was fortunate to have great teachers , last year went to visit the observatory of Arcetri .Scrive : - " it was thanks to these series of randomness that the stars went for the first time in my life. I've never been one of those girls that you melted of romance under the firmament , but in order to dodge the dusty abyss of bad books in which he wanted to drag prof. Tieri , I preferred to raise the nose in the air and give the opportunity for a science that until then had had no particular importance in my life : astronomy "
That's how he embarked on the road astronomical . Strictly for the record prof. Tresi was his teacher that he wanted her to do a thesis laboratory but not on old books of 1800 yars , but you obviously after a week " declined " the offer .
His scientific career stat is high quality , It was the first Italian woman to direct the Astronomical Observatory of Trieste for 23 years, worked in America, for NASA , ESA .
Of you I have always loved his mental acuity , his stubbornness , his sobriety on his way to speak Florentine , his ever present smile . I only regret not to have known anything, not even when she came to Milan in the presentation of one of his books. His books I read them all , some read multiple times , such as " my life by bike ."
This post I wrote a few months after his death, but remains an icon for me to follow, to be admired. Hello Margaret.
Rewrite some more or less famous quote :
• From the ethical point of view it is heartbreaking to think of what suffering the animals are subjected , real cars from meat, bred to gain weight quickly , to reproduce rapidly in crowded conditions , to meet the throat of the man who thinks the master of all other species , when in fact it is quite possible to live without meat, like myself , vegetarian since birth
• Walk me wrong, cycling vo ' better. It is a less strenuous. Until recently pedaled often , obtaining balance, desire to do and will
• The fault of Eve was that of wanting to learn , experiment , investigate on its own merits the laws that govern the universe , the earth, your body, to reject the teaching top-down , in a word Eva is the curiosity of science against the passive acceptance of the faith ...
• Astronomy taught us that we are not the center of the universe , as we have thought long and as someone wants us to think even today. We're just a tiny planet around a star very common. Ourselves, intelligent beings , we are the result of stellar evolution , we are made of matter of the stars

Equal protection

As well as animals, plants also have their own immune system is also complex as nostro.Non fact that everyone knows the famous "aspirin", whose active ingredient is acetyl salicico, comes from a compound that plants exploit for their defense for thousands of years as salicylic acid or other components such as, for example, ROS, reactive oxygen compounds. were born But when these defensive systems? Pamela Ronald, University of California botany and Brucer Beutler, geneticist Script Research Institute, published a study in Science which state that the innate immune system of plants and animals works the same modo.Ma take a step back, what is the innate immune system? and what differs from that acquired? The innate immune system mediates the first protection against infections, usually consists of epithelial barriers, through specialized cells and substances near naturally equipped with antibiotic power, also potentiates the work immunity acquisita.L 'immunity acquired instead, provides a slower response but more specific, is mediated by antibodies (produced by B lymphocytes) and by T lymphocytes

 The researchers, with a study that lasted 15 years, they found an amazing similarity in the way in which these two kingdoms difendono.I researchers examined the nature of the protein receptors that recognize and attach to antigens encouraging response immunitaria.Nonostante the species-specificity of the proteins have found rich regions of leucine, amino acid important for binding antigenico.Inoltre, once recognized the intruder, in a similar manner both plants and animals, lal trigger immune response with the same proteins, those of the non-complex kinase RD.Ecco another proof of the fact that all living beings are derived from a common ancestor, even if one were needed.

Frederick Griffith and the Transforming Principle

Have you ever wondered who was the first to discover something, that experiment did, and with that logic did? For those who have studied biology have surely heard of Griffith experiment!
Frederick Griffith was a medical officer engaged in the study of the bacterium pneumoniae: Streptococcus  pneumonia.
  In 1928suggested that there was a transforming principle that did change a strain of bacterium to another! He took a strain of pneumococcus bacteria, called S (S = Smoth, smooth) producing bacterial colonies smooth and shiny, but highly infectious and a strain called R (R = rough), whose colonies are wrinkled but harmless. Well, what did he do?
There are two versions of the S strain, IIS and IIIS, and an occasional strain S can change in strain R, and never by IIR to IIIS. The two strains differed in that the S strain IIIS caused the death of infected mice, which occurred in mice infected with strain IIS.
He injected in mice a mixture of live bacteria IIR (non-virulent) and with the heat-killed bacteria of type IIIS. All mice were killed by live bacteria which drew type IIIS, bacteria that could not be created for type-specific mutations by IIR.
Griffith concluded that some bacteria were transformed by IIR components of bacteria IIIS, material that he called Transforming Principle.
Then there were many researchers who resumed his experiments to understand the cellular components that allows the transformation, experiments such as Avery, Hershey and Chase experiments which I'll discuss in the future.

the DNA, the deoxyribonucleic acid ..

 

The earth 4.5 billion years, and presumably life appeared between 3 and 4 billion years ago. How did life I will talk about in another post, as it has created the DNA, that union of fundamental molecules that transmit the information necessary for life. Let's see what it looks like DNA. The structure was discovered in 1953 by J.Watson and F. Crick and with the help of R.Franklin. Unfortunately, all we remember that the discovery was made only by the first two scientists, but in reality much it is due to Franklin, who died before receiving the Nobel personally along with his colleagues.The DNA (deoxyribonucleic acid) is composed of monomers called nucleotides from a pentose, the deoxyribose (red circle), a nitrogenous base (circle rooster) and a phosphate group (green circle). The DNA has a double helix shape, ie there are two filaments that are wound connected to each other thanks to the nitrogen bases, The two strands follow two opposite directions, calls the 5 'and 3', which serve to give the direction to the processes in which the DNA is involved, such as duplication and transcription. Consider a single filament and see how he is both chemically and its structure in space. The nucleotides are linked together via the covalent bond between the phosphate group of a nucleotide and the carbon of the other nucleotide, called phosphodiester bond. The phosphate group (PO42-) is linked to the 5 carbon sugar, while the nitrogenous base is linked to the carbon 1.

 The nitrogenous bases are divided into two groups, purines and pyrimidines: the first are the Adenine (A) and Guanine (G), the latter are the Cytosine (C) and Thymine (T). These four nitrogenous bases do not join to case, but may bind to each other only in accordance with the sequence obliged CG, TA. The linear arrangement of these bases damage to the cell the information that serves, in fact, a gene is composed of thousands of purines and purimidine, and according as they are placed can give information or the other.The DNA looks like in the image:
The base pairs are spaced apart by 3.4 nm, thus leading to the formation of two grooves, one major and one minor. The two grooves are very important for the binding of macromolecules necessary for the function of some processes.But it is disposed in the cell's DNA? Assuming that in nature there are two types of cells, prokaryotic, without the eukaryotic nucleus and with the nucleus, the DNA we find it grouped within the cytoplasm in the first type of cells and always grouped in the second type, but within a structure called the nucleus. I voluntarily omitted because the viruses are "entities" particolari.M to exist in nature other structures of DNA, both in circular form, as in bacteria and mitochondria, the cDNA, but also snDNA A-DNA and B-DNA, which present difference in space of the grooves, as well as the Z-DNA which rotates clockwise so, then in the opposite direction to DNA.ed other types that will speak in the future
The DNA is said to be supercoiled, ie wound on whether stessto thanks to the proteins called histone and non-histone to form chromatin. All together to form the chromosome. In practice, the DNA strand is wound atorno to the protein, like a yoyo to form a kind of pearl necklace which in turn is raggruppatom called nucleosome. But why evolution has led to what? Serves both to protect this group that the genetic material, which is huge. The nucleosome is arranged in a structure which we call chromosome, what we all know that in humans is in the form of X or Y.In Nature there are other structures of DNA, both in circular form, as in bacteria and mitochondria, but also A-DNA and B-DNA, which have difference in space of the grooves, as well as the Z-DNA which rotates clockwise, then in the opposite direction to the DNA.
In the next post will describe the processes of replication, that is, as the DNA is duplicated, the transcription process, that is, as mRNA (messenger RNA) copies information for Ribosomes, the protein factories, but also RNA and all the processes that occur in cell.

The Kama Sutra of dragonflies

Even before I finished reading the book I was already anticipating its review. A book about nature, animals and plants but also of men. A book to read and re-read a book to recommend, and to give.

I'm talking about the book by Marc Giraud, "The Kama Sutra of dragonflies", 303 pages to be read and reread, in which Giraud shows us, shows us and tells us many oh so many peculiarities of nature around us. At the very beginning, a foretaste, as a small appetizer, that will tell us later, promising fact the phrase: "And to think that there are people in the country is bored ...

I would like to bring a few examples, even if only for incuriosirvi, both for what concerns the book that as regards the nature that surrounds us ... did you know that a louse when it is still in the womb has an embryo inside her body? or that when the caterpillars eat the stem of corn plants, the plants are able to recall the wasps are able to parasitize the caterpillars? ... here is an example of communication from plant to animal!

But still ... that male blue tits smell of the nest with lavender and mint and these perfumes are constantly renewed in order to attract the females not only have the function insecticide and fungicide?

Have you ever wondered then how do the curls to mate? well, if you read the book you'll find out!

This book is also able to reflect on the nature whether in the city or the bush ...

Happy reading!

I'm here

... and I'm here , after long time...
... after reflected I decide to create this blog!
From the title already you understand it will be a blog based on science, science in general and in particular about biology and about biology evolution, my bigger passions!




My name is Sergio Di Matteo, I am graduate student in Biology with specialization in bio-evo... it means animal biology  and biology evolution.

When I was a child always loved and respected the nature, I've always admired, I was fascinated by the insect's world, so small but immensely complex and in the evening I loved watching the constellation in the sky.

When I went to the sea I spent hours and hours with mask and snorkel to wacth, wacth and watch the fish and other sea animals.
The mountain walks were daily and I was spend my free time between trees and paths.
After the hight school I did two years of engineering but then I realized that my interests were differents and thanks to my friend Laura I am incribed at the Faculty of Biology at the university of Study of Milan and for this I will never stop thanking her.
Now every lesson is for me source of information to assimilate with a great pleasure...at the second years I discovered scientists like Stephen Jay Gould, Richard Dawkins, Niles Eldrege and the famous Charles Darwin...love at first sight!

that's it!