Exams

The outer most electrons that are free to move are called valency electrons that are responsible for the conductivity in the metal atoms.

A galvanic cell is also known as voltaic cell provides electrical energy from the chemical energy.

A UPS (Uninterruptible Power Supply) is a device that provides battery backup when the electrical power fails or drops to an unacceptable voltage level.

Small UPS systems provide power for a few minutes; enough to power down the computer in an orderly manner, while larger systems have enough battery for several hours.

Random mutations are the ultimate source of genetic variation. Mutations are likely to be rare and most mutations are neutral or deleterious, but in some instances, the new alleles can be favored by natural selection. Polyploidy is an example of chromosomal mutation.

Mutations are changes in the DNA. A single mutation can have a large effect.

1) mutation - an alteration in DNA sequence, various types

2) intragenic recombination - results in entirely new associations of genes not present in either parental genome.

Two forms of intragenic recombination:

a) crossing over
b) independent assortment
3) reticulation – acquisition of genetic material from unrelated or relatively unrelated sources (e.g., hybrid species, horizontal gene transfer).

The concept of carbon credit for manufacturers originated with the Kyoto Agreement (Protocol) of 1997.

Common properties of Minerals are :

1. All minerals are formed in a natural process.

2. Minerals are inorganic

3. Minerals are crystalline solids.

4. Every mineral is an element or compound with a definite chemical composition.

Bookkeeper is the only English word that has three consecutive double letters.