Five major Arthropod classes
Arachnida. mites, ticks, spiders, scorpions.
Chilopoda. Centipedes.
Crustacea. (crabs, lobsters, shrimp.
Diplopoda. Millipedes.
Hexapoda. Insects.
so your answer will be mollusks
Its the Eccentricity of the earth. (shape of Earth's Orbit around the sun, whether it is more circular or ovular.)
Variation means difference in genetic makeup between individuals within a specie.
B. Global warming accelerates the greenhouse effect
Cell has cell membrane<span> (also known as the </span>plasma membrane<span> or </span>cytoplasmic membrane<span>) it is a </span>biological membrane<span> that separates the </span>interior<span> of all </span>cells<span> from the </span>outside environment.<span> The cell membrane is </span>selectively permeable<span> to </span>ions<span> and </span>organic molecules<span>and </span>controls the movement of substances<span> in and out of cells.</span><span>The basic function of the cell membrane is to protect the cell from its surroundings.</span>
