慢速英语1500基础单词 [more]

a lot of [much or many]
We had a lot of rain.

carry out [to do; to put into effect]
Please carry out the plan.

pass a bill [approve]
Congress is expected to pass a bill to cut taxes.

take steps [to start to do something]
The government will take steps to halt inflation.

(WORDS USED IN VOA SPECIAL ENGLISH SCIENCE PROGRAMS)

antibodies [special proteins, produced in the blood, that kill hamp3ful bacteria]
The body's defense system creates different antibodies for each disease it fights.

atom [a very small part of all things; the smallest part of an element that can join with parts of other elements]
All matter is made of atoms.

bacteria [living things that are one cell and can be seen only through a microscope; some cause disease]
Some bacteria cause disease.

cell [a small mass of living material that is part of all plants and animals]
All plants and animals are made of cells.

chromosome [a line of genes; most human cells contain 46 chromosomes]
Chromosomes carry the genes that make each of us different.

compound [a substance containing two or more elements]
A compound contains two or more chemical elements.

dense [close together; thick]
Lead is a dense material.

electron [a small part of an atom that has an electrical force]
An electron is a small part of an atom.

element [one of more than 100 substances known to science that cannot be separated into other substances]
An element cannot be separated into other substances.

enzyme [a special kind of protein; it produces changes in other substances without being changed itself]
An enzyme can change other substances without being changed itself.

fetus [unborn young]
A human embryo becomes a fetus after eight weeks.

fission [a splitting; in atomic fission, the nucleus of an atom is split to produce nuclear energy]
Nuclear fission splits atoms to produce energy.

fusion [a joining together; in atomic fusion, atomic particles are joined together to produce nuclear energy]
Nuclear fusion joins atoms to produce energy.

genes [parts of cells that control the growth and development of living things; genes from the mother and father are passed to the child; genes contain nucleic acid]
Genes in the cell control the growth and development of living things.

genetic engineering [the science of changing the genes of a living thing]
Genetic engineering changes the genes of a living organism.

gravity [the force that pulls things toward the center]
Gravity is the force that pulls things toward the center.

image [a reproduction of the appearance of a person or thing]
An image is a picture of someone or something.

laser [an instrument that makes a thin, powerful light]
A laser makes a thin, powerful beam of light.

magnet [a piece of iron or other material that has a pulling force; this pulling force is called magnetism]
A magnet pulls on objects of iron or steel.

molecule [the smallest amount of a chemical substance that can exist]
A molecule is the smallest part of a chemical substance.

nerve [a thin piece of tissue that sends infomp3ation through the body to and from the brain]
Nerves carry infomp3ation between the brain and the other parts of the body.

nucleic acid [a molecule that holds the genetic infomp3ation necessary for life; there are two kinds of nucleic acid: DNA (deoxyribonucleic acid) and RNA (ribonucleic acid)]
A molecule of nucleic acid holds the genetic infomp3ation necessary for life.

nucleus [the center part of an atom or cell]
The nucleus is the center part of an atom or cell.

nutrient [a food or substance that makes plants, humans or animals grow]
Food is a nutrient that makes humans and animals grow.

organ [a part of the body that has a special purpose, such as the heart or brain]
The heart and the brain are organs.

organism [a living thing, often so small it can be seen only through a microscope]
An organism is a living plant or animal of any size.

particle [a very small piece of matter]
A particle is a very small piece of matter.