In simple terms Almost all of a person’s DNA sits in the nucleus of each cell. A small amount sits somewhere else, inside the mitochondria. Mitochondria are the structures that convert energy from food into a form cells can use. They carry a little DNA of their own, called mitochondrial DNA, or mtDNA. How it […]
Mitochondrial DNA is a small, separate loop of DNA inside a cell's mitochondria, inherited almost entirely from the mother.
In simple terms A mole is a counting unit for very small things. One mole is a fixed number of particles, the way a dozen is a fixed number of eggs. The number is enormous because atoms are tiny. NIST calls the mole a shorthand way to talk about huge numbers, especially of tiny things.
A mole is the SI unit of amount of substance: exactly 6.02214076 times 10 to the power 23 entities, such as atoms, molecules or ions.
In simple terms The moment magnitude scale is the standard way seismologists state how big an earthquake was. It is written Mw, and it has replaced the Richter scale for most serious work. It describes the earthquake at its source. One earthquake has one magnitude, wherever you happened to be standing. How it works The
The moment magnitude scale, written Mw, states an earthquake's size from the slip, fault area and rock rigidity at its source.
In simple terms Monetary policy is how a central bank steers an economy by changing the cost of money. Its main lever is a short-term interest rate. Move that rate and the cost of mortgages, business loans and savings tends to move with it. How it works A committee meets on a fixed schedule and
Monetary policy is the action a central bank takes to influence how much money is in an economy and what it costs to borrow.
In simple terms Every survey misses people. Nonresponse bias is what happens when the people it misses differ from the people it reaches. If the difference has nothing to do with the question being asked, the estimate can still be sound. If it does, the number is wrong, and a larger sample will not rescue
Nonresponse bias is the error that appears when the people who answer a survey differ from those who do not in ways that matter.
In simple terms Occam’s razor says that when two explanations account for the same evidence, the one assuming less is usually the better bet. It is not a law of nature. It is a working preference, a way of deciding where to start when the evidence alone cannot separate two ideas. How it works Philosophers
Occam's razor is the rule of thumb that when two explanations fit the evidence equally well, you should prefer the one assuming less.
In simple terms Orbital eccentricity is a single number that says how far an orbit departs from a perfect circle. It is written as e. A value of 0 is a circle, and the larger the number, the more stretched the path. How it works NASA’s Jet Propulsion Laboratory defines eccentricity as the ratio of
Orbital eccentricity is a number describing how stretched an orbit is, from 0 for a circle to above 1 for a path that never returns.
In simple terms Orthostatic hypotension is a drop in blood pressure that happens when someone stands up. For a few seconds, less blood reaches the brain. The usual result is lightheadedness or dizziness on rising. About one third of people who meet the clinical definition feel nothing at all. How it works The definition is
Orthostatic hypotension is a drop in blood pressure on standing, of at least 20 mm Hg systolic or 10 mm Hg diastolic within three minutes.
In simple terms A percentage point is the unit for the gap between two percentages. You find it by simple subtraction: a rate that moves from 10% to 12% has risen by 2 percentage points. The term exists to prevent a common mix-up. That same move from 10% to 12% is also a 20% increase,
A percentage point is the simple difference between two percentages: a rate rising from 10% to 12% has risen by 2 percentage points.
In simple terms pH tells you how acidic or basic a water based liquid is. Lemon juice is acidic, a baking soda solution is basic, and pure water sits between them. The scale runs from 0 to 14. Seven is neutral, below 7 is acidic, and above 7 is basic, also called alkaline. How it
pH measures how acidic or basic a water based solution is, on a scale where 7 is neutral, lower is acidic and higher is basic.