science grad.8 CPT 4

Question 1

atom

Answer 1

the basic unit of matter

Question 2

adhesion

Answer 2

force of attraction between different kinds of molecules

Question 3

acid

Answer 3

a compound that forms hydrogen ions (H+) in solution; a solution with a pH of less than 7

Question 4

amino acid

Answer 4

compound with an amino group on one end and a carboxyl group on the other end

Question 5

base

Answer 5

a compound that produces hydroxide ions (OH-) in solution; a solution with a pH of more than 7

Question 6

compound

Answer 6

substance formed by the chemical combination of two or more elements in definite proportions

Question 7

cohesian

Answer 7

attraction between molecules of the same substance

Question 8

chemical reaction

Answer 8

process that changes, or transforms, one set of chemicals into another set of chemicals

Question 9

electron

Answer 9

negatively charged particle; located in the space surrounding the nucleus

Question 10

elements

Answer 10

pure substance that consists entirely of one type of atom

Question 11

enzyme

Answer 11

protein catalyst that speeds up the rate of specific biological reactions

Question 12

iconic bond

Answer 12

a chemical bond formed when one atom gives up one or more electrons to another atom.

Question 13

lipid

Answer 13

any of a class of organic compounds that are fatty acids or their derivatives and are insoluble in water but soluble in organic solvents

Question 14

carbohydrate

Answer 14

Carbohydrates are a class of naturally occurring compounds, probably the most abundant and widespread organic substances in nature.

Question 15

covalent bond

Answer 15

A chemical bond formed when electrons are shared between two atoms

Question 16

nucleic acid

Answer 16

a biopolymer that carries genetic information and is involved in gene regulation functions

Question 17

protien

Answer 17

A molecule made up of amino acids

Question 18

polymer

Answer 18

any of a class of natural or synthetic substances composed of very large molecules, called macromolecules, that are multiples of simpler chemical units called monomers

Question 19

solution

Answer 19

a homogeneous type of mixture of two or more substances

Question 20

monomer

Answer 20

atoms or small molecules that bond together to form more complex structures such as polymers

Question 21

mixture

Answer 21

A mixture is a physical combination of two or more substances that aren’t chemically joined

Question 22

nucleus

Answer 22

the structure in a cell that contains the chromosomes