Spiders have to absorb salts and wastes while humans have microscopic subunits in the kidneys called to filter blood. spiders have malpighian tubules to absord salts and wastes while humans have microscopic subunits in the kidneys called nephrons to filter blood.

Spiders have malpighian tubules to absorb salts and wastes while humans have microscopic subunits in the kidneys called nephrons to filter blood. Malpighian tubules remove wastes from insects by producing urine and solid nitrogenous waste, which are then excreted from the body.

An autotrophic protist - they can perform photosynthesis and mainly consist of unicellular algae. they can be divided into number of systematic group according to the shape of their cell and the type of photosynthetic pigments they use.