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How does Messi keep the ball close to himself

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The science of how Messi keeps the ball close to himself photo credit: ZaleDesigns Messi is a magician with the ball at his feet. He's in my opinion the best player in the sense that he can control the ball so well, runs so fast with the ball & changes the direction at full speed like it's a walk in the park. For starters he started playing very early (at 3) which is crucial if you want to be a good player. In that aspect, he's God gifted as he had dribble skills which is genetic in my opinion. Height He is short which means a low center of gravity so it's difficult to push him off the ball. That's why we see that anyone rarely can topple him down, instead players much larger than him lose possession to him. So his short height suits his style of play & is a blessing in disguise. Change of pace Messi changes his pace really well. He starts slow and runs directly at the defender which means the defender has to stop & focus on him. When he reac...
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what is sexual reproduction?

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Biology - Sexual Reproduction


Introduction

  • The sexual mode of reproduction comprises the process of combining DNA from two different individuals.

  • There are two germ-cells (responsible for producing a new organism); one is large and contains the food-stores whereas the other one is smaller and likely to be motile.

  • The motile germ-cell, normally, is known as the ‘male gamete’ and the germ-cell containing the stored food is known as the ‘female gamete.’

Sexual Reproduction in Flowering Plants

  • As shown in the image given below, flowers have different parts, such as sepals, petals, stamens, and carpels. Among these, stamens and carpels are the reproductive parts and contain the germ-cells.


Stamen is the male reproductive part, which produces pollen grains (yellowish substance).

  • Carpel, which is present in the center of a flower, is the female reproductive part.

  • Carpel is made of three parts.

  • The bottom part, which is swollen, is the ovary; the middle part, which is elongated, is known as the style; and the terminal part, which may be sticky, is known as the stigma.


The ovary contains ovules and each ovule has an egg cell.

  • The male germ-cell that produced by the pollen grain fuses with the female gamete present in the ovule.

  • The fusion of the germ-cells or fertilization produces zygote, which is capable of growing into a new plant.

  • The flower, which contains either stamens or carpels, is known as unisexual, such as papaya, watermelon, etc.

  • The flower, which contains both stamens and carpels, is known as bisexual, such as Hibiscus, mustard, etc.

Reproduction in Human Beings

  • Human beings have typical sexual reproduction process where mature male and female mate to produce a new baby.

Male Reproductive System

  • The male reproductive system produces the germ-cells; further, other part of the reproductive system delivers the produced germ-cells to the site of fertilization.

  • The formation of sperms or germ-cells takes place in the testes.

  • The formation of sperm typically requires a lower temperature than the normal body temperature.

  • The testes secrete hormone, namely testosterone that brings changes in the appearance of boys at the time of their puberty.

  • The formed sperms are then delivered through the vas deferens, which unites with a tube coming from the urinary bladder.

  • The urethra, likewise, acts as a common passage for both the sperms and urine.

  • The sperms are fluids that consist of mainly genetic material; it has a long tail that helps to move towards the female germ-cell.

Female Reproductive System

  • The female germ-cells or eggs are produced in the ovaries.

  • The egg is transported from the ovary to the womb through a thin oviduct known as fallopian tube.

  • The two oviducts unite and form an elastic bag-like structure known as the uterus, which opens into the vagina through the cervix.

  • During the sexual intercourse, most likely, the egg and the sperm (zygote) get fertilized and implanted in the lining of the uterus.

  • The thickened lining (of the uterus) and richly supplied blood nourish the growing embryo (in the uterus).

  • The embryo receives nutrition from the mother’s blood with the help of a special tissue known as placenta.

  • Likewise, the development of a child inside the mother’s body, takes about nine months.

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The Fundamental Units Of. Life

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carbon and it's compound

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Chemistry - Carbon and its Compounds Introduction Carbon plays very important roles for all living beings. The amount of carbon in the earth’s crust is merely 0.02%, which is available in the form of minerals such as carbonates, hydrogen-carbonates, coal, and petroleum. The presence of carbon in the atmosphere of the earth is 0.03%, in the form of carbon dioxide. Compounds of Carbon Almost all carbon compounds (except a few) are poor conductors of the electricity. The diamond and graphite both are formed by carbon atoms; however, the difference lies between them in the manner in which the carbon atoms are bonded to one another. In diamond, each atom of the carbon, is bonded to four other carbon atoms and form a rigid three-dimensional structure (see the image given below). In graphite, each atom of the carbon, is bonded to three other carbon atoms in the same plane, which gives a hexagonal array (see the image given below) − There is also difference in some physical structu...
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What happened to the dinosaurs?

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WHAT REALLY HAPPENED TO THE DINOSAURS One day 66 million years ago, an asteroid the size of a mountain struck near the Yucatán Peninsula with an explosive force equivalent to 100 trillion tons of TNT. In that cataclysmic instant, the 165-million-year reign of the dinosaurs came to an end. The asteroid theory of the dinosaurs’ demise was first suggested in 1980. More than a decade later, the identification of the Chicxulub Crater in the Gulf of Mexico established where and when. Using an impact calculator developed by geophysicists from Purdue University and Imperial College London, researchers obtained a pretty good idea of what occurred at the moment of impact and immediately after—what is known as the K-Pg (Cretaceous-Paleogene) extinction event. The asteroid struck the Earth at 40,000 miles (64,000 kilometres) per hour, creating a crater more than 115 miles across and instantly vaporizing thousands of cubic miles of rock. Any creature close enough to witness the strike was immediate...
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