science Q

Your body has many different kinds of cells. Though they might look different under a microscope, most cells have chemical and structural features in common. In humans, there are about 200 different types of cells, and within these cells there are about 20 different types of structures or organelles.

Dark chocolate is loaded with nutrients that can positively affect your health.
Made from the seed of the cocoa tree, it is one of the best sources of antioxidants on the planet.
Studies show that dark chocolate (not the sugary crap) can improve your health and lower the risk of heart disease.
1. Very Nutritious

If you buy quality dark chocolate with a high cocoa content, then it is actually quite nutritious.
It contains a decent amount of soluble fiber and is loaded with minerals.

A 100-gram bar of dark chocolate with 70–85% cocoa contains:
11 grams of fiber
67% of the RDI for iron
58% of the RDI for magnesium
89% of the RDI for copper
98% of the RDI for manganese
It also has plenty of potassium, phosphorus, zinc and selenium

2. Powerful Source of Antioxidants
ORAC stands for “oxygen radical absorbance capacity.” It is a measure of the antioxidant activity of foods.
Basically, researchers set a bunch of free radicals (bad) against a sample of a food and see how well the antioxidants in the food can "disarm" the radicals.
The biological relevance of ORAC values is questioned, because it's measured in a test tube and may not have the same effect in the body.
However, it is worth mentioning that raw, unprocessed cocoa beans are among the highest-scoring foods that have been tested.

3. May Improve Blood Flow and Lower Blood Pressure
The flavanols in dark chocolate can stimulate the endothelium, the lining of arteries, to produce nitric oxide

One of the functions of NO is to send signals to the arteries to relax, which lowers the resistance to blood flow and therefore reduces blood pressure.

Many controlled studies show that cocoa and dark chocolate can improve blood flow and lower blood pressure, though the effects are usually mild.

4. Raises HDL and Protects LDL From Oxidation
Consuming dark chocolate can improve several important risk factors for heart disease.
In a controlled study, cocoa powder was found to significantly decrease oxidized LDL cholesterol in men. It also increased HDL and lowered total LDL for those with high cholesterol.
Oxidized LDL means that the LDL ("bad" cholesterol) has reacted with free radicals.

This makes the LDL particle itself reactive and capable of damaging other tissues, such as the lining of the arteries in your heart.

5. May Protect Your Skin From the Sun
The bioactive compounds in dark chocolate may also be great for your skin.
The flavonols can protect against sun damage, improve blood flow to the skin and increase skin density and hydration.
The minimal erythemal dose (MED) is the minimum amount of UVB rays required to cause redness in the skin 24 hours after exposure.
In one study of 30 people, the MED more than doubled after consuming dark chocolate high in flavanols for 12 weeks

6. Could Improve Brain Function.
The good news isn't over yet. Dark chocolate may also improve the function of your brain.
One study of healthy volunteers showed that eating high-flavanol cocoa for five days improved blood flow to the brain.
Cocoa may also significantly improve cognitive function in elderly people with mental impairment. It may improve verbal fluency and several risk factors for disease, as well.
Additionally, cocoa contains stimulant substances like caffeine and theobromine, which may be a key reason why it can improve brain function in the short term.

Apples are among the most popular types of fruit in the world.
They are the fruit of the apple tree (Malus domestica), originally from Central Asia, and are grown all over the world.

Apples are high in fiber, vitamin C and various antioxidants. They are also very filling, considering their low calorie content. Studies show that eating apples can have multiple benefits for health (1,2,3,4)
They taste delicious on their own and are usually eaten raw, but they are also used in various recipes, juices and drinks.

There are many different types, with a variety of colors and sizes.

FACTS: for apple as per 100 grams

                                              Amount
Calories                                          52
Water                                           86 %
Protein                                         0.3 g
Carbs                                         13.8 g

Lysosomes: They contain membrane-bound sacs with powerful digestive enzymes
(enzymes are made by RER) to digest the worn-out cell organelles. When the cell
gets damaged, lysosomes may burst and the enzymes digest their own cell, hence
called as “Suicidal bags of a cell”. It is a waste disposal system of the cell.

A lysosome is a membrane-bound organelle found in nearly all animal cells. They are spherical vesicles that contain hydrolyticenzymes that can break down many kinds of biomolecules

Lysosomes are surrounded by a membrane composed of phospholipids that separate the inside of the lysosomes from the membrane's external environment. Phospholipids are the same cellular molecules that make up the cell membrane surrounding the entire cell. Lysosomes range in size from 0.1 to 1.2 micrometers.

After meal, you are always advisable to have a gap for atleast 15–20 minutes even before drinking water. The logic is, when you start eating your food, digestive juice starts to secrete for digestion and if you drink water in between, this will dilute the digestive juices and you may face problem in digestion.
Specialists usually suggest to have any fluid at least 30–45 minutes before and after your meal.

Really depends on what kind of acid. Beverages like coke or fruit juices both contain acids. For coke, it's carbonic acid, and for citrus fruits, it's citric acid (and about a million others (exaggeration)).
If a person were to down HCl or sulfuric acid or any other strong acid though...that's a whole different story. Proteins are almost instantly denatured, breaking down cellular structures and causing necrosis. Rapid dehydration occurs, causing cells to lose water rapidly. And when cells are damaged this much, apoptosis occurs; cells that lose water detach from one another as well. This leads to ulcers forming in one's alimentary canal (throat, esophagus, etc). It is excruciating.

A new study suggests that eating chocolate can help you stay thin. Researchers at the University of California-San Diego found that people who frequently eat chocolate have lower body-mass indexes than people who don’t. Other evidence indicates that chocolate can also ward off strokes, heart attacks, and diabetes. So here are 11 reasons to indulge in some s’mores this summer.

1. Chocolate decreases stroke risk
A Swedish study found that eating more than 45 grams of chocolate per week—about two bars worth—led to a 20 percent decrease in stroke risk among women. Chocolate contains flavonoids, whose antioxidant properties help fight strokes.

2. Chocolate reduces the likelihood of a heart attack
Other studies show that eating chocolate prevents blood clots, which in turn reduces the risk of heart attacks. Blood platelets clump together more slowly in chocolate eaters.

3. Chocolate protects against blood inflammation
Eat one Hershey’s dark chocolate bar per week, and your risk of heart disease will decrease.About 6.7 grams of dark chocolate per day keeps the blood inflammation-inducing proteins away. Just like your mother always told you.

4. Chocolate helps with maths
British psychologists found that flavanols (a class of flavonoids, which are found in chocolate) helped people with their mental math. Study subjects had an easier time counting backwards from a randomly-generated number between 800 and 999 after drinking a cup of hot chocolate than they did without the cocoa. “The findings suggest students who binge on chocolate when revising for exams may gain a real benefit from doing so.”

5. Chocolate may prevent cancer
Cocoa contains a compound called pentameric procyanidin, or pentamer, which disrupts cancer cells’ ability to spread. When researchers from the Lombardi Comprehensive Cancer Center at Georgetown University treated cancer cells with pentamer back in 2005, the proteins necessary for cancer growth were suppressed and the cells stopped dividing.

6. Chocolate reduces the risk of diabetes
The Italians know a thing or two about good eating.And a small study from the University of L'Aquila, in Italy, found that eating chocolate increase insulin sensitivity, which reduces the rise of diabetes.

7. Chocolate is good for your skin
“Some people say that I eat too many chocolate bars …” Remember that aceninfomericial from the 90s? No? Well, it doesn’t matter. Not only does it not cause breakouts, it’s actually good for your skin! (Well, dark chocolate at least.) Flavonoids found in dark chocolate protect women’s skin from the sun’s UV rays, according to German scientists. But that doesn’t mean you can skip the sunscreen.

8. Chocolate can control coughs
The most delicious way to kick your cough, apparently, is chocolate. One of the sweet’s chemical components, theobromine, seems to reduce the activity of the vagus nerve, the part of the brain that triggers coughing fits. Scientists are even working on a cough-quelling drug that uses theobromine in place of codeine—a narcotic common in cough medicine.

9. Chocolate improves blood flow
In 2008 Harvard scientists forced test subjects to undergo “two weeks of enhanced chocolate intake.” A fortnight of chocolate face-stuffing, they found, sped up blood flow through their subject’s middle cerebral arteries. In other words, more chocolate means more blood to your brain.

10. Chocolate strengthens your brain
Researchers at the Johns Hopkins University found that dark chocolate shields cells in your brain, and accordingly protects it from damage caused by stroke. Epicatechin, a compound found in chocolate, significantly reduced the brain damage in mice who suffered strokes, they found. Scientists at California's Salk Institute also found that epicatechin improved mice’s memories.

11. Chocolate makes you live longer
Jeanne Louise Calment lived to the age of 122—the oldest anyone has ever lived. She ate two and a half pounds of dark chocolate per week. Harvard researchers found that eating chocolate actually adds two years to your life expectancy.

But don’t just start binging on chocolate! Most of the chocolate you buy in the grocery store is heavily processed, which means that it has lost many of its healthy chemicals. And some of the research supporting chocolate’s healthy characteristics was paid for by chocolate manufacturers.

There is no reason to consider sour curd bad, it is just the matter of taste, sour curd and far more active bacteria than the sweet.

While the invention of the telescope made the Cosmos accessible to human observation, the microsope opened up smaller worlds, showing what living forms were composed of. The cell was first discovered and named by Robert Hooke in 1665. He remarked that it looked strangely similar to cellula or small rooms which monks inhabited, thus deriving the name.

Eukaryotic cells are cells that contain a nucleus and organelles, and are enclosed by a plasma membrane. Organisms that have eukaryotic cells include protozoa, fungi, plants and animals. These organisms are grouped into the biological domain Eukaryota. Eukaryotic cells are larger and more complex than prokaryotic cells, which are found in Archaea and Bacteria, the other two domains of life

Eukaryotic cells contain a variety of structures called organelles, which perform various functions within the cell. Examples of organelles are ribosomes, which make proteins, the endoplasmic recticulam, which sorts and packages the proteins, and mitochondria, which produce the energy molecule adenosine triphosphate (ATP).

Prokaryotic cells are cells that do not have a true nucleus or most other cell organelles. Organisms that have prokaryotic cells are unicellular and called prokaryotes. Bacteria and archaea are prokaryotes. Prokaryotic cells can be contrasted with eukaryotic cells, which are more complex. Eukaryotic cells have a nucleus surrounded by a nuclear membrane and also have other organelles that perform specific functions in the cell.

Prokaryotic cells do not have a true nucleus that contains their genetic material as eukaryotic cells do. Instead, prokaryotic cells have a nucleoid region, which is an irregularly-shaped region that contains the cell’s DNA and is not surrounded by a nuclear envelope. Some other parts of prokaryotic cells are similar to those in eukaryotic cells, such as a cell wall surrounding the cell (which is also found in plant cells, although it has a different composition).

Sweating is an important process to cool down the body when we get too hot. It produced by sweat glands on the surface of the skin.

The reaction in which more reactive element displaces less reactive element known as displacement reaction.

For example:-

CuSO4 +Fe ----------> FeSO4 +Cu

In above reaction the Fe (Iron) is more reactive than Cu (Copper) according to modern periodic table.Hence it displaces Cu from the solution of Copper Sulphate and form Ferrous Sulphate and Copper metal.

In more easy way AB+C ------>A+BC In this C is more reactive than A so C will displace A and combines with B

First of all what are vaccines? Vaccines are substances used to produce immunity to diseases in the living body. Immunity is the ability of the body to resist a diseases by natural or artificial means.

Smallpox vaccine, the first successful vaccine to be developed, was introduced by Edward Jenner in 1796. He followed up his observation that milkmaids who had previously caught cow pox did not later catch smallpox by showing that inoculated cowpox protected against inoculated smallpox. The word "vaccine" is derived from Variolae vaccinae (i.e. smallpox of the cow), the term devised by Jenner to denote cowpox and used in the long title of his An enquiry into the causes and effects of Variolae vaccinae, known by the name of cow pox.Vaccination, the term which soon replaced cowpox inoculation and vaccine inoculation, was first used in print by Jenner's friend, Richard Dunning in 1800.[3] Initially, the terms vaccine/vaccination referred only to smallpox, but in 1881 Louis Pasteur proposed that to honor Jenner the terms be widened to cover the new protective inoculations being introduced.

First of all what are antibiotics? Antibiotics (anti=against,bios=life) are chemical substances produced by microorganisms such as fungi and bacteria which kills or stops the growth of disease causing microorganisms .

The first antibiotics was discovered by ALEXANDER FLEMING in 1798 by a fungus PENICILLIUM which was PENICILLIN

His research and study during his military career inspired him to discover naturally antiseptic enzyme in 1921, which he named lysozyme. This substance existed in tissues and secretions like mucus, tears and egg-white but it did not have much effect on the strongly harmful bacteria. Six years later; as a result of some intelligent serendipity, he stumbled on discovering penicillin. It was in 1928 when he observed while experimenting on influenza virus that a common fungus, Penicillium had destroyed bacteria in a staphylococcus culture plate. Upon subsequent investigation, he found out that mould juice had developed a bacteria-free zone which inhibited the growth of staphylococci. This newly discovered active substance was effective even when diluted up to 800 times. He named it penicillin.

He was knighted in 1944 and was given the Nobel Prize in Physiology or Medicine in 1945 for his extraordinary achievements which revolutionized the medical science.

There was no science before 1572, the year that Tycho Brahe saw a new star in the night sky above him. To be sure, the Greeks had made efforts to present their knowledge of nature in a systematic fashion, but they lacked the tools — more specifically they lacked the ways of thinking — that have allowed investigators over the past 300 years to question the traditions that have preceded them, to probe the inner workings of nature, and in so doing to build increasingly informative accounts of the world that surrounds us. These ways of thinking were invented over the course of the 17th century: a period whose momentous significance for all that would come after amply justify naming it ‘the scientific revolution".

The history of science is the study of the development of science and scientific knowledge, including both the natural and social sciences. Science is a body of empirical, theoretical, and practical knowledge about the natural phenomena, produced by scientists who emphasize the observation, explanation, and prediction of real world phenomena. Historiography of science, in contrast, studies the methods employed by historians of science.

Viruses are the smallest of all the microorganisms. They are not cell and do not contains cell organelles. They cannot grow and multiply on their own . For this they need a living host (being). They do not show any characteristic of living creature . They do not: feed, respire, excrete, grow and multiply. The only thing which they have in living is they have genetic material which is surrounded by a protein coat

In humans, viruses can cause a verity of diseases .main are of 4 types

1. MEASLES
2. CHICKENPOX
3. POLIO
4. HEPATITIS B
General preventive measures to fight these viruses are:

Salt in the ocean comes from rocks on land.
The rain that falls on the land contains some dissolved carbon dioxide from the surrounding air. This causes the rainwater to be slightly acidic due to carbonic acid (which forms from carbon dioxide and water).

As the rain erodes the rock, acids in the rainwater break down the rock. This process creates ions, or electrically charged atomic particles. These ions are carried away in runoff to streams and rivers and, ultimately, to the ocean. Many of the dissolved ions are used by organisms in the ocean and are removed from the water. Others are not used up and are left for long periods of time where their concentrations increase over time.

Two of the most prevalant ions in seawater are chloride and sodium. Together, they make up over 90 percent of all dissolved ions in the ocean. Sodium and Chloride are 'salty.'

The concentration of salt in seawater (salinity) is about 35 parts per thousand, on average. Stated in another way, about 3.5 percent of the weight of seawater comes from the dissolved salts.

By some estimates, if the salt in the ocean could be removed and spread evenly over the Earth’s land surface it would form a layer more than 500 feet thick, about the height of a 40-story office building

While a sip of beer probably wouldn't kill it plants can tolerate some alcohol because they sometime produce it themselves . In conditions where there isn't enough oxygen,such as waterlogged soil, plants obtain the energy by fermentation stored sugars which produces alcohol as by-product . But if you're intent on a big night out with your potted pal,make sure he sticks to mineral water , as alcohol is significant quantities will destroy his cellular membranes and vital proteins.

An acid called capsaicin ,found in the skin on the inside of chilli pods,cause the burning sensation . Many people think that chilli seeds are also hot , but they contain no capsaicin. However the chemical is found in the flash that holds the seeds in place and when they are taken out this flesh normally comes out with them , these reducing the chillies spiciness. Despite capsianis punch , it makes up only 0.1 percent of chilli.

Microorganisms (micro=small and organisms =living) Tiny organisms which are not visible with unaided eyes. Microoganisms are every where surround you there will be millons of microorganisms present which you cant see. Some of them can harm you and some of them can help you. There are 5 main groups of microorganisms. These are:
1. Bactria
2. Fungi
3. Algae
4. Protozoa
5. Viruses

Microorganisms are been used from years to years back in perpartion of food items such as : curd, bread and cheese.For example :
In making of curd (bactria)

You have seen your mother making curd for you at home.What she actually do? She adds up a little amount of curd to warm milk at night and keeps the vessle containing milk and curd in a warm place. And in the morning when you see it, the liquid milk is turned into semi-solid curd.And when the curd is made it is transferred to a cool place. Otherwise,the curd will becomes sour in taste.

Have you ever oberved that why does the milk turns into curd?
This is because the milk contains milksuger which is known as lactoes. Milk contains certain bacteria, in which one of the bacterium is known as Lactobacillus,it helps in the formation of curd and it grows in the warm place, in night when it is kept undisturbed these bacteria grows and reacts with milk and turns it into curd.It converts the lactoes (milk suger)into lactic acid.And the process of curd formation form milk is called curdling of milk.