What type of gene mutation not shown in transparency 19a would also change every amino acid after that mutation ?

typically, most spiders possess eight eyes. however, others have as many as 12, and some don't have any. these eyes are for detecting light from dark, deciphering shapes and for gathering their prey.

measuring light intensity

light meters can be used to measure light intensity. the meter is held at the soil surface and pointed in the direction of the maximum light intensity, and then the meter is read.

errors can be made when measuring light intensity by accidentally shading the light meter. the reliability of the results can be checked by taking many samples.

for example, no new evidence will demonstrate that the earth does not orbit around the sun (heliocentric theory), or that living things are not made of cells (cell theory), that matter is not composed of atoms, or that the surface of the earth is not divided into solid plates that have moved over geological timescales .