The yield sign means slow down, be ready to stop, and let traffic (including people walking or riding bikes) pass before you go ahead. Go only when it is safe.
Cellulose is a polysaccharide made up of glucose monomer units.
The Earth's tilt on it's axis
Enzymes like peroxidase are important biological catalysts because they convert toxic hydrogen peroxide into water and oxygen. This enzyme is found in plants and animal cells.