DARK MATTER

Dark matter is the universe’s biggest mystery. Astronomers can tell that there is something invisible in the spaces between stars, since it’s creating enough of a gravitational pull to bend starlight as it travels toward Earth. However, no one knows what dark matter looks like or what it is made from.

IT’S A MYSTERY
Five percent of the visible universe of stars and planets is normal matter. However, this matter would not have enough gravitational pull to hold the galaxies together, so astronomers know that there must be another kind of matter, even if it’s invisible. Dark matter isn’t made of atoms and does not reflect light or any other kind of radiation, but it appears to make up a quarter of the matter in the universe.



MAPPING IT OUT
This computer simulation shows how dark matter is spread throughout the universe. The yellow areas show the highest concentrations of dark matter. These regions have enough gravity to pull together visible matter, creating galaxies.

What’s the matter?
This image of a distant galaxy cluster shows a ring of dark matter around its center. The ring would not normally be visible, but we can tell where it is from the way that the gravity of dark matter bends the light of distant galaxies.

The Bullet Cluster
The Bullet Cluster was formed when two galaxy clusters collided, one tearing through the middle of the other like a bullet. The cluster’s normal matter (which appears pink here) has been slowed down in the collision by a drag force. However, the dark matter has continued to move outward without slowing, creating a light-bending aura.

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LIFE ON THE EARTH

by – penserstudypoint.com

Life on the earth, as we all know that depends on the liquid tamperature that dominates the earth’s surface.

Most life on the world needs average temperatures between the freezing and boiling points of water.

The earth’s orbit is that the right distance from the sun to produce these conditions. If the world were a lot of nearer to the sun, it’d be too hot-like Venus—for vapour to condense and type rain.

If it were a lot of farther away, the layer would be thus cold-like Mars—that its water would exist solely as ice. The world conjointly spins, if it didn’t, the aspect facing the sun would be too hot and therefore the different aspect too cold for water-based life to exist.

The size of the world is additionally excellent always. It’s enough mass to stay its iron and nickel core liquefied and to stay the atmosphere—made of light-weight aerosolized molecules needed always (such as N2, 02, CO2, and H,0)-from flying off into house.

Although life on earth has been enormously resilient and reconciling, it’s profit tough guy from a positive temperature vary. Throughout the 3.7 billion years since life arose, the common surface temperature of the world has remained among the slender vary of 10-20 °C (50–68 °F), even with a 30-40% increase within the sun’s energy output.

One reason for this can be the evolution of organisms that modify levels of the temperature-regulating gas carbonic acid gas within the atmosphere as a vicinity of the carbon cycle.

For almost 600 million years, gas has created up concerning twenty first of the degree of earth’s atmosphere. If this gas content born to concerning V-J Day, it’d be deadly for many varieties of life. If it exaggerated to concerning twenty fifth, gas within the atmosphere would in all probability ignite into a large fireball.

This gas content of the atmosphere is essentially the results of producer and client organisms interacting within the carbon cycle. Also, as a result of the event of photosynthesizing microorganism that are adding gas to the atmosphere for quite two billion years, ozone gas within the layer protects us and plenty of different varieties of life from an over dose of UV.

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The Bending of Light in a Gravitational Field

Let us consider a ray of light that shines through a window in an elevator at rest, as shown in figure. The ray of light follows a straight line path and hits the opposite wall of the elevator at the point P.

Let us now repeat the experiment, but let the elevator accelerate upward very rapidly, as shown in figure. The ray of light enters the window as before, but before it can cross the room to the opposite wall the elevator is displaced upward because of the acceleration. Instead of the ray of light hitting the wall at the point P, it hits at some lower point Q because of the upward acceleration of the elevator.

To an observer in the elevator, the ray of light follows the parabolic path, as shown in figure. Thus, in the accelerated coordinate system of the elevator, light does not travel in a straight line, but instead follows a curved path. But by the principle of equivalence the accelerated elevator can be replaced by a gravitational field. Therefore light should be bent from a straight line path in the presence of a gravitational field.

The gravitational field of the earth is relatively small and the bending cannot be measured on earth. However, the gravitational field of the sun is much larger and Einstein predicted in 1916 that rays of light that pass close to the sun should be bent by the gravitational field of the sun.



Another way of considering this bending of light is to say that light has energy and energy can be equated to mass, thus the light-mass should be attracted to the sun. Finally, we can think of this bending of light in terms of the curvature of spacetime caused by the mass of the sun. Light follows the shortest path, called a geodesic, and is thus bent by the curvature of spacetime.

Regardless of which conceptual picture we pick, Einstein predicted that a ray of light should be deflected by the sun by the angle of 1.75 seconds of arc. In order to observe this deflection it was necessary to measure the angular deviation between two stars when they are far removed from the sun, and then measure the deflection again when they are close to the sun. Of course when they are close to the sun, there is too much light from the sun to be able to see the stars.

Hence, to test out Einstein’s prediction it was necessary to measure the separation during a total eclipse of the sun. Sir Arthur Eddington led an expedition to the west coast of Africa for the solar eclipse of May 29, 1919, and measured the deflection. On November 6, 1919, the confirmation of Einstein’s prediction of the bending of light was announced to the world.

More modern techniques used today measure radio waves from the two quasars, 3c273 and 3c279 in the constellation of Virgo.

A quasar is a quasi-stellar object, a star that emits very large quantities of radio waves. Because the sun is very dim in the emission of radio waves, radio astronomers do not have to wait for an eclipse to measure the angular separation but can measure it at any time.

On October 8, 1972, when the quasars were close to the sun, radio astronomers measured the angular separation between 3c273 and 3c279 in radio waves and found that the change in the angular separation caused by the bending of the radio waves around the sun was 1.73 seconds of arc, in agreement with the general theory of relativity.

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short series – 8 SKIN

SKIN

The skin has two primary layers: the epidermis (outer) and the dermis (inner). The epidermis has two important sublayers the stratum germi nativum and the stratum corneum. The epidermis is made up of cells called keratinocytes; these cells make up the epithelial tissue.

It is in the epidermis layer where blisters and calluses can form. Blisters occur when friction such as what might develop between the skin and the inside of a shoe-causes layers to separate within the epidermis or between the epidermis and the dermis.

As these layers separate, tissue fluid may build up, leading to a blister. While blisters often result because of fric tion, calluses result from pressure. When exposed to increased amount of pressure, mitosis will occur at a rapid rate, causing the epidermis to thicken.

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TIME TRAVEL & WORMHOLES – myth or truth

penserstudypoint.wordpress.com

At present, we are changing according to the time. Time not change according to us. But what if we change the time. Time travel An imaginary thought.

We don’t know if It will be future or past. It is like changing time’s direction to past or increasing time’s speed to future, but if it will be possible in the future, It may be travel to past.

According to relativity, Nothing can travel faster than light (3 × 10⁸m/sec.). At light speed, mass will be infinite (according to relativistic mass formula) . And the length of object will be zero (according to length contraction formula). But if we travel with the light speed, what can we see? Is there any color? Is there any boundary of anything? Only white light appears on moving with light speed. Everything is white.

At present, black holes are the best source to see the past. Where, light cannot even pass through. The body’s shape , space-time will be changed at light speed . 

Even if we travel with such a high-speed it will take 2000 years in reaching and coming back to Earth from a thousand light years away star(or any Terrestrial body in space). When you travel such a large distance, an atom, the smallest unit of matter also traveled to that distance, and it is amazing to imagine.

Wormholes

According to scientists, a wormhole is a cylindrical path between two heavy bodies in space. It is not from any science fiction movie. It is scientist’s thoughts. 

Wormhole forms by two giant bodies have very high gravity value like black holes. If a path is a thousand light years long, wormholes can make it a few million miles long. So, it may be a possibility to travel faster than light.

In 1835, Albert Einstein and Nathan Rosen called them Einstein-Rosen Bridge. Bridge that connects two, bodies that are light years far away from each others.

Worm holes are like tunnels in space connecting to distant bodies because space and time are flexible (according to Einstein). Through the wormholes we can cover very long distance in a very short period.

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According to another theory we can travel with light speed. The theory proposed that, if we are stable and space can move. In this theory, a large heavy body contract the space with fast and alternately a negative mass, behind the large body, can expand that contracted space.

Negative mass is only a hypothetical Idea. It behaves just opposite of positive mass that we have.

Positive mass can contract the space while a negative mass can expand it. Due to this, we remain stable on a position and space can move.

If all this phenomena possible, we can cover large distance with speed of light by stay at a place without any change.

To be continue…

Hope u like it

THANK YOU

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Glucose, Fat, and Protein Metabolism

Glucose, Fat, and Protein Metabolism

In the muscles and other tissues, cortisol increases the breakdown of pro tein into amino acids.

Those amino acids are used to produce additional glucose (via a metabolic pathway called gluconeogenesis) in the liver.

Cortisol also conserves glucose for the brain and spinal cord by blocking the actions of insulin (which will be discussed later in this chapter) inhibiting glucose absorption into other tissues.

Cortisol also stimulates the release of fatty acids and glycerol from adipose tissue.

Glycerol is used in gluconeogenesis, while fatty acids are made available for energy to other tissues to preserve glucose for the brain.

Cortisol reduces protein reserves everywhere except in the liver.

As proteins continue to be broken down in muscles and in other tissues, blood levels of amino acids rise.

The additional amino acids are used for gluco neogenesis, glycogen formation, and protein synthesis in the liver.

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Growth Hormone levels

Growth hormone, also called somatotropin, is a large polypeptide hormone produced by somatotroph cells in the anterior pituitary that plays a signifi cant role in growth and metabolism. It primarily affects bone, muscle, and tissue growth.

Without sufficient growth hormone, an individual would suffer from short stature. Too much growth hormone would result in gigan tism. For normal growth to occur, the body requires energy, which growth hormone provides through protein synthesis and the breakdown of fats.

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COLOURS OF FEATHER

Feathers, are important parts of a bird’s flying equipment’. A bird’s tail feathers are used for lifting, steering, and breaking, and these are perfectly symmetrical, to allow a balanced and smooth flight.

Along the sides of a bird’s feathers are barbs, which if separated, look like a fringe, or even like the threads that stick out from the edge of a piece of unstitched cloth. Since these barbs end in hooks, they hook on to one another efficiently, making a strong, but light flying wing.

There here are two sources of feather colour- pigments, and the physical structure of the feather. Many feathers are coloured by a combination of these features. Pigments are chemical compounds that absorb certain wavelengths of light while reflecting others. The colours you see are those reflected back. Feathers coloured by pigments, range from crow black to canary yellow, and cardinal red.



Many colours, such as blue, are a result of feather structure. When light hits these feathers, it hits microscopic structures on the feather that act as prisms to reflect a colour.
No blue pigment is known in birds. Shimmering iridescent colours such as those found in peacocks, are caused by special structures, air bubbles, or films on feather surfaces.

These modifications interfere with the bending and scattering of light to strengthen some wavelengths, and cancel out others.

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The Hypothalamus and Pituitary Gland

The hypothalamus and pituitary gland together serve as the command center of the endocrine system, and the core of the relationship between the endocrine and nervous systems. Together, they regulate virtually every physiological activity in the body.

As mentioned earlier, the nervous and endocrine systems also regulate each other: neurohormones from the hypothalamus direct the release of endocrine hormones, and hormones from the endocrine system regulate nervous system activity.

Pancreas

Pancreas

The pancreas is an irregular-shaped gland that is located just below the stomach and adjacent to the duodenum of the small intestine. It averages between 4.7 and 5.8 inches (12 and 15 centimeters) in length, and a little over 0.8 inches (2 centimeters) in thickness. For descriptive purposes, it is divided into three major sections, although there is little difference in the physiology of the sections. The head is located closest to the duodenum and is connected to the digestive tract by two ducts. The hepatopancreatic duct is a common duct formed by the linking of the bile duct and pancreatic ducts. A second duct, called the duct of Santorini, directly connects the pancreas to the duodenum. Moving away from the duodenum and the head of the pancreas are the regions called the body and tail.

The pancreas actually represents two separate organs, both of which contribute to digestion, which are integrated into a single structure. A por tion of the pancreas is an exocrine gland, meaning that it secretes com pounds into a cavity.

The second major area of the pancreas is the endocrine tissue, which secretes chemicals into the bloodstream. In general, the exocrine functions of the pancreas can be described as those directly involved with the processing of nutrients in the duodenum, while the endo crine is best described as those functions that involve hormones and the regulation of glucose homeostasis in the body. Both types of tissue exist throughout the pancreas.