Biology Review

autotrophs

Organisms that are known to feed themselves

The chloroplast, a tiny body within plant cells, is the power generator for life on earth. True/False

True

Sunlight is a form of energy called

electromagnetic energy, or radiation

molecule

The smallest unit of a pure substance that consists of two or more atoms held together by a chemical bond.

diatomic

containing two atoms

elements

substances made up of only one type of atom

shell

the path surrounding the nucleus of an atom in which electrons are normally located

radiation

transfer of heat or energy through rays of various wavelengths

atomic weight

the average relative mass of each element

chlorophyll

a green pigment in plants that serves to trap the Sun's energy for photosynthesis

carotenoid pigment

a pigment ranging in color from yellow to red; helpful in capturing the Sun's light energy for use in photosynthesis

photosynthesis

a process that involves the use of carbon dioxide and water in the production of glucose and oxygen using the Sun's energy

electron

a subatomic particle fundamental to all matter, existing in orbit around the nucleus of an atom, and carrying a negative charge

proton

a subatomic particle fundamental to all matter, existing in the nucleus, having a positive charge, and about equal in mass to a neutron

neutron

a subatomic particle, fundamental to all matter except hydrogen, that exists in the nucleus and has about the same mass as a proton (but carries no charge)

Calvin cycle

the dark reaction process of photosynthesis that uses carbon dioxide for the synthesis of carbohydrates

atomic mass

the mass of an element; approximately equal to the number of protons and neutrons in an atom's nucleus

atomic number

the number of protons in the nucleus of the atom; also the number of electrons around the nucleus

nucleus

the positively charged center of an atom that contains both the protons and neutrons of the atom

atom

the smallest unit of an element that still retains the chemical properties of the element

chloroplast

the tiny body that contains chlorophyll; part of the cell in which photosynthesis takes place

The Sun's rays travel as waves of radiation. There are short waves and long waves.

The shorter the waves, the stronger the radiation.

compound

a chemical substance composed of atoms of two or more elements chemically bonded to one another

autotroph

an organism that can make its own food