Standard Grade Biology
Investigating cells
Word
Glossary
Meaning
Active Site
part of an enzyme molecule to which the substrate attaches
Aerobic respiration
chemical reaction to release energy which requires oxygen
Amylase
an enzyme which speeds up the breakdown of starch
Atom
the smallest part of an element which can exist chemically
Catalase
Cell wall
an enzyme which speeds up the breakdown of hydrogen
peroxide
a substance which speeds up a reaction but remains
unchanged
cellulose layer around the outside of a plant cell
Chloroplast
structure within a plant cell which contains chlorophyll
Chromatid
identical copy produced when chromosomes double
Chromosome
thread like structure made up of several genes
Chromosome number
number of chromosomes in each cell of a species of animal or
plant
the number of solute molecules in a specific volume of
solvent
the difference between two concentration levels
Catalyst
Concentration
Concentration
Gradient
Cytoplasm
the fluid part of a cell
Denatured
permanent damage caused to an enzyme by high temperature
Diffusion
movement of molecules from high to low concentration
Distilled water
pure water consisting of 100% water molecules
DNA
chemical which makes up a gene
End product(s)
compound formed at the end of a reaction
Enzyme
chemical found in living cells which acts as a catalyst
(Cell) Membrane
semi-permeable layer surrounding the cytoplasm in all cells
Metabolism
all of the chemical activity taking place within an organism
Mitosis
cell division which produces two identical cells
Word
Meaning
Molecule
two or more atoms joined together by chemical bonds
Nucleus
control centre of a cell
Optimum conditions
conditions in which an enzyme works most efficiently
Osmosis
diffusion of water molecules across a semi- permeable
membrane
Pepsin
an enzyme which breaks down protein
pH
a measure of acidity/alkalinity
Phosphorylase
an enzyme which synthesizes starch
Selectively permeable
allows some molecules to pass through but not others
Solute
substance which is dissolved in a liquid
Solvent
liquid used to dissolve another substance
Specific Activity
each enzyme only acts on one substrate
Spindle
fibrous structure which pulls chromosomes apart
Stain
coloured dye used to show up cell structure more clearly
Substrate
the molecule on which an enzyme works
Synthesis
building up a larger molecule
Vacuole
cavity in the cytoplasm of a plant cell