Page 18 - ICC Science Dictionary (spreads)

Word Definition Topic(s) Word Definition Topic(s)

dark matter An unidentified form of matter P8 decomposi- The process of breaking down B7a, B7b
that accounts for galaxies rotating tion material to release nutrients back
faster than their visible mass into the soil.
should cause. deficiency In the diet, a deficiency happens B7a, B7b
data Information, either qualitative Thinking if there is too little of a particular
or quantitative, that has been scientifically nutrient.
collected. deficiency A disease that develops because B3
daughter When a cell divides, the new cells B1a, B1b disease an organism (plant or animal)
cells produced are called daughter cells. does not have enough vitamins or
daughter The nuclei (centres of atoms) P4 mineral ions.
nuclei that are produced by a nuclear define Specify the meaning of Command
reaction. In nuclear fission the something. word
parent nucleus splits into two deflect To cause something to change P7
smaller daughter nuclei and direction.
releases energy.
deforestation The cutting down of trees and B7a, B7b, C9
dc motor An electrical device that uses P7 forests to allow a different land use.
direct current to produce a
turning effect. deformation When an object is stretched or TP4, P5
squashed, which requires work.
decay When plants wither and die. B7a, B7b
delocalised Electrons that are not associated C2
deceleration Slowing down or negative P5 with a particular atom, eg in a
acceleration, eg the car slowed metal, outer electrons can be free
down with a deceleration of 2 ms ². to move through the solid.
-
decommis- To deactivate or remove in a safe P1 denature To change the shape of an B2, C7
sion manner. enzyme's active site, for example

decompose If a substance decomposes, B7a, B7b, C3 because of high temperatures
it breaks down into simpler or extremes of pH. Denatured
compounds or elements. enzymes no longer work.

decomposer An organism which eats dead TB2, B7a, B7b denatured If a substance is denatured, its B4
organisms, fallen leaves, animal structure and function is altered.
droppings, etc, and breaks them This can be caused by heat,
down into simpler materials. altered pH or by chemical agents.