Sharpen Your General Knowledge

[Shamim Ansary]

What Sea Creatures Plant Their Own Gardens?

The spider crab not only plants its own seaweed garden, but it plants the garden right on its own body! This crab snatches pieces of seaweed, cuts them into smaller pieces, and attaches the cuttings to the hairs on its legs and shell.

The seaweed cuttings take root on the crab, and eventually grow to completely cover it. By the time the spider crab is finished with its garden, it looks just like a mass of seaweed, and is perfectly hidden from its enemies.

Another kind of crab, the coral-gall crab, collects small sea creatures called corals and places them all around its body. As a coral grows, it surrounds itself with a shell, and when it dies, the shell remains.

So the coral-gall crab soon finds itself surrounded by a coral shell, with small holes in the shell where the corals once lived. These holes permit water and food particles to reach the imprisoned crab.

So while the coral shell protects the crab from its enemies, the crab can never escape from its shell. It spends the rest of its life locked inside the coral, and may even give birth to young crabs inside the shell!

[Shamim Ansary]

What Plant Is Really Two Plants In One?

You may have seen the small, moss-like plants called lichens covering rocks or the branches of old trees. Though you’d never guess it from looking at these plants, lichens are really two plants in one: a fungus and an alga.

The fungus and alga in a lichen live so closely together that you’d need a microscope to tell them apart. The relationship of this fungus and alga in a lichen is called symbiotic, which means that both the fungus and alga help each other survive.

The lichen’s fungi send branchlike pieces into rocks or pieces of wood from which they absorb moisture and minerals. The algae make food by photosynthesis, the process that all green plants use to make food from sunlight, minerals, and water.

So, the fungus “waters” the alga, and the alga “feeds” the fungus.

[Shamim Ansary]

How Much Oxygen Do Plants Consume at Night and How Is Sleeping With a Live Plant Dangerous?

There is just a grain of truth in the idea, as green plants do absorb some oxygen for use in respiration, the mirror image of photosynthesis.

Photosynthesis can occur only when there is light, so at night plants are absorbers of oxygen, on balance.

However, true danger would result only from an extremely large body of plants in a very tightly closed sleeping chamber with a very limited supply of oxygen.

Another person in a room would be a far heavier oxygen consumer than one plant.

These principles of gas exchange in photosynthesis and respiration were explored in the late eighteenth century by Jan Ingenhousz, a Dutch botanist.

Once Joseph Priestley had discovered oxygen and plants’ role in producing it from carbon dioxide, there was a great vogue for putting flowers in sickrooms to “purify” the air.

Ingenhousz was skeptical about the benefits.

His experiments showed that only the green parts of plants add oxygen, and then only if placed in strong light; flowers and other non-green parts, as well as green leaves left in darkness, used up oxygen just as animals did, he found.

In aerobic respiration, plants use free oxygen, usually from the air, for chemical reactions that release energy from organic substances; sugar and oxygen react to produce carbon dioxide, water and chemical energy.

In photosynthesis, carbon dioxide and water react in the presence of light energy to produce sugar and oxygen.

During the day, both processes occur, but photosynthesis proceeds more rapidly than respiration, and the carbon dioxide produced is immediately used in photosynthesis.

Excess oxygen from the photosynthesis escapes into the air.

At night, however, photosynthesis ceases and respiration continues, so that green plants are absorbing oxygen and producing carbon dioxide.

[Shamim Ansary]

How Do Coal and Oil Produce Energy?

Millions of years ago, when much of the earth was a swampy forest, billions of plants and animals died and fell into the shallow water.

The oxygen, hydrogen, nitrogen, and carbon in these living things were acted upon by bacteria and pressure over thousands of years, freeing gases from the decayed matter and leaving behind only the carbon.

Coal and oil are made up mainly of carbon. The difference is that coal was under more pressure as it formed, and the carbon atoms arranged themselves in solid form.

When coal or oil burns, it combines with oxygen in the air, producing carbon monoxide and other gases. This chemical change produces a great deal of heat energy.

So when we burn coal or oil to heat or light our homes, or to heat water at electricity plants, we’re really burning the remains of plants and animals that lived ages ago!

[Shamim Ansary]

Where Do Astronauts Get Oxygen for Extended Space Missions On the International Space Station?

However, when the space station built, plans were announced to have it carry equipment to recover oxygen indirectly from the carbon dioxide crew members exhale. astronauts

NASA’s Johnson Space Center tested means to recycle air and water used by volunteers sealed in an airtight chamber with a limited amount to breathe and to drink.

Mechanical and chemical means were being used to recycle all the air and water, including urine.

Past tests involved using wheat plants to recycle breathing air, and by 1997, sixty and ninety day tests using plants and/or physiochemical recycling were planned.

In a life-support system for the space station designed at NASA’s Marshall Space Flight Center in Huntsville, Alabama, carbon dioxide is reclaimed from the exhaled air by a concentrator.

The 95-percent-pure carbon dioxide is burned with hydrogen in a carbon dioxide reduction device, yielding water and some waste products, either carbon or methane.

This water is used as drinking water on the space station.

Some water from the hygiene system, dirtier water, is put in an oxygen generator, an electrolyzer that breaks it down into its two components, hydrogen and oxygen, by electrolysis.

The oxygen is to be fed back into the cabin, closing the cycle.

The hydrogen is used in the propulsion system to keep the space station at the proper attitude and to reboost it into the proper orbit as the orbit decays.

Oxygen requirements are about 1.8 pounds per day per person. On past space flights, carbon dioxide was recaptured but not reused.

Initially, the Soviet Union used a multi-step chemical recovery system to obtain oxygen for its extended space flights.

But they switched to an electrolyzer-type process, with the supply vehicle, Progress, bringing up water that is then electrolyzed.

U.S. missions have also supplied breathable air.

[Shamim Ansary]

How Can the Sun Burn Without Oxygen?

Nothing can burn on earth without the presence of oxygen.

As what we call “fire” or “burning” is a chemical reaction in which atoms of oxygen combine with atoms of carbon from the fuel, the substance being burned, to produce carbon dioxide, light, and heat.

Since fire needs oxygen, and there is almost no oxygen in space, then how can the sun burn constantly? Well, the sun isn’t “burning” in the same sense that a fire burns on earth. The sun produces energy the same way that a hydrogen bomb produces energy.

In this process, hydrogen is changed into helium, but some hydrogen is instead converted into energy. So the sun continues to “burn” and produce light and heat without oxygen.

[Shamim Ansary]

What Is a Tectonic Plate and How Many Tectonic Plates Are There On Earth?

The Earth is not a solid shell, but rather slabs of rock that scientists call Tectonic Plates.

These plates, seven large plates and several smaller ones, have been moving for millions of years.

They hold the ocean floors and the continents. Their movements cause new seafloor to form and earthquakes and volcanoes to occur.

Mountain ranges are formed when two plates collide, causing rock to fold and rise.

Scientists aren’t quite sure what causes the tectonic plates to move, but they believe the intense heat of the Earth’s core is a factor.

[Shamim Ansary]

Are All Stars Burning Out and Are New Ones Forming?

Stars are being born as well as dying, but the rate varies greatly from galaxy to galaxy.

Stars form from huge clouds of dust and gas. If a cloud begins to contract because of its own gravity, its interior heats up as gravitational energy is converted to heat energy, reaching millions of degrees, and nuclear reactions begin that change one element into another, releasing energy.

The pressure tends to expand the cloud back out, but eventually equilibrium is reached. That is essentially what a star is, a mass of gas at equilibrium between inward pressure from gravity and outward pressure from nuclear reactions.

A star has a finite lifetime because it is burning fuel. For 90 percent of its life, it burns hydrogen into helium. When the hydrogen is used up, the pressure decreases, but gravity never disappears, so the star contracts until the temperature climbs again, this time reaching hundreds of millions of degrees, while reactions convert helium to carbon and oxygen.

The star can then remain stable for a briefer time. Eventually the star dies, when the reactions no longer produce energy, but only consume it.

[Shamim Ansary]

What Does a Third Degree Burn Mean and What Is the Difference Between a First Degree Burn and a Second Degree Burn?

The seriousness of a burn is assessed in degrees depending on the number of layers of skin involved.

A sunburn, or a red mark on a finger touched to an iron, is a first-degree burn.

A second-degree burn blisters.

Third-degree burns mean that all skin is destroyed right down to the layer of tissue under the skin.

Burns on faces, hands, and feet can be more serious than a wound on the thigh, for example, because of the importance of these body parts.

Burns to the genital area are also more dangerous because they are vulnerable to infection.

Second and third degree burns always require immediate medical attention, the first thirty seconds are crucial, to remove the cause of the burn, cool the skin, and protect against infection.

The chance of having a stroke is 1 in 6.

The chance of dying from heart disease is 1 in 3.

The chance of getting arthritis is 1 in 7.

The chance of getting the flu in the course of a year is 1 in 10.

The chance of contracting the human version of mad cow disease is 1 in 40,000,000.

The chance of dying from any kind of fall is 1 in 20,666.

[Shamim Ansary]

Where Did the Expression “the Third Degree” Come From and What Does It Mean?

The third degree is a very difficult and sometimes brutal questioning, especially by police.

In fact, without its sinister connotation, the expression comes from the Masonic Lodge and its three degrees of membership, each requiring an increasingly difficult examination.

The first is Entered Apprentice, the second is Fellowcraft, and the third degree, the one most difficult to pass, is Master Mason.

[Shamim Ansary]

Why Do Toes and Fingers Wrinkle In the Bathtub and After a Swim?

Actually, toes and fingers don’t wrinkle in the bathtub at all.

They are puckering from swelling. The thick outside layer of skin called the stratum corneum takes on excess water when soaked, sort of like dried beans when soaked in water.

The underlying skin and connective tissue don’t absorb water and don’t swell along with it.

This anchoring of the skin-tissue layers makes the swelled area appear puckered.

It’s not just the fingers and toes that do this, though they are easier to see because the stratum corneum in those areas is thickest.

When you see your fingers and toes wrinkling, take it as a sign that your entire body is on guard to prevent water, soap, dirt, and germs from invading through your skin.

[Shamim Ansary]

How Was Soap Invented and When?

The world would be a far less fragrant place without soap, and what would we buy Grandma for her birthday?

Come Clean. It’s anybody’s guess how people washed in the distant past. Maybe they didn’t bother and just picked off the crusty bits. Soap is an unlikely combination of fat and any alkaline substance, so it’s amazing that anyone invented it at all.

The ancient Mesopotamians somehow worked out that mixing animal fat with wood ash makes a substance that can clean clothes and people. They made soap in clay cylinders as far back as 2800 BC.

The ancient Egyptians were using soap made from fats and alkaline salts by about 1500 BC. Maybe they found out about it from their neighbors, the Mesopotamians.

The ancient Romans were very fond of bathing and built public baths all over their empire, but they didn’t use soap. There’s some evidence to suggest that Roman women used a soap-like substance on their hair starting from around AD 50.

People were making soap in Europe by the 600s, but they weren’t using it nearly enough. The Middle Ages saw personal hygiene at its lowest point. Soap was a luxury item until the middle of the 19th century, so be very glad you weren’t around in those days.

Getting into scrapes: Instead of using soap the ancient Romans cleaned themselves by oiling their bodies, then scraping off the oil using a special scraper called a ‘strigil’. Really posh Romans would have a slave do the scraping for them.

If you’re fed up of smelling of roses, make your own soap and you can smell however you like!

EQUIPMENT NEEDED

a neutral glycerin soap bar (available from health or craft shops), a knife, a wooden spoon, a microwaveable bowl, a microwave, various food colourings, essential oils. moulds (you can improvise with washed-out food or drink containers – or buy proper soap moulds from a craft shop)

BASIC SOAP

Cut the soap into small chunks or grate into thin shavings. Be careful not to cut yourself!

Put the soap into a microwaveable bowl and heat in a microwave until it has melted (about 50 seconds) or you can melt it in a saucepan on a cooker.

If you’d like to add colour, add it now drop by drop, stirring with a wooden spoon, until your soap is the colour you want. You can also add a scent at this point. mixing a few drops of the essential oil of your choice.

Pour the liquid soap into your mould. The soap will take about 45 minutes to harden, depending on the size of it.

STRIPY SOAP

To create stripes of colour in your soap, follow basic steps, but then rather than pouring all the colour into one mould, divide it into four moulds. You will end up with a shallow layer of colour at the bottom of each. Now you need to repeat this process using a different colour each time until you have built up four stripy soaps.

Try to add each new layer of coloured soap while the previous layer is still a bit soft. When all your layers are in place, leave it to harden fully.

SWIRLY SOAP

To create swirls of colour in your soap, follow basic steps 1-4 but don’t add any colouring to the soap until it is poured into the mould.

When the soap is in its mould, add a few drops of one colour at one end, and a different colour at the other end (add other colours too, if you want). When you’ve added your drops of colour, take a toothpick or spoon and use it to stir the colours into the soap and create swirls. Leave to harden.

CHUNKY SOAP

To create chunks of colour in your soap, you need first of all to cut up a colored soap (home-made or bought) into little chunks and put these chunks into the bottom of your mould.

Then make a different colored soap, following basic steps 1-4, pouring the liquid soap into the mould over the chunks. Leave to harden. (You can insert other things into the soap bar, such as a plastic spider to scare your mom!)

[Shamim Ansary]

What Part of the Body Has the Thickest Skin?

The part of the body that has the thickest skin is pretty much as you’d suspect.

The soles of the feet and palms of the hands have the thickest layer of skin. After that, the back and nape of the neck are the thickest.

The thinnest layer of skin is around the eyes, particularly the eyelids.

[Shamim Ansary]

Why Do We Wrinkle as We Age and How Can We Prevent It?

Skin changes that cause wrinkles do accompany aging, as the deeper layer of skin, the dermis, gets thinner.

But it happens more quickly in sun-exposed areas and in people who smoke. The breakdown of two kinds of molecules, collagen and elastin, is at fault.

Collagen type 1 is the molecule that makes up the bulk of the skin. Loss of this type of collagen, the same type found in bones, affects the elderly, and smoking can make it worse.

At least five studies have found that smoking is associated with “smoker’s face,” one that is prematurely aged by fine wrinkles that can accentuate the coarser wrinkles that occur along the lines of expression.

As for elastin, the stretchy molecules that help support the skin, ultraviolet rays cause direct damage, breaking the molecules down.

To help avoid wrinkles as you age, avoid smoking, stay out of the sun, routinely use hats and sunscreens, and use a good moisturizer, which holds water in the dermis and plumps it up.

[Shamim Ansary]

Is the Weather Warmest When the Earth Is Closet to the Sun?

Surprisingly, the earth’s distance from the sun has nothing to do with weather!

The earth’s path around the sun is not a perfect circle, but an ellipse, or egg shape. The earth is actually nearest the sun around January 2, when it’s “only” 91,402,000 miles away. This point is called the perihelion. At the earth’s aphelion, or farthest point from the sun, it’s 94,510,000 miles away. And this point falls around July 5.

Why is our weather coldest when the earth is closest to the sun? Because weather is determined mostly by the tilt of the earth’s axis at various times of the year.

When it’s winter here, the earth is tilted in such a way that much of the sun’s radiation reaches us at an angle, and bounces off our atmosphere. In summer, the sun’s rays reach us more directly, and therefore the weather is warmer. Also, in winter the days are shorter, and much of the sun’s heat is reflected off the earth by snow.

The earth doesn’t travel around the sun at a constant speed, either; the speed varies at different points in the earth’s orbit!