Question: What is the greenhouse effect? Need Assignment Help? Group of answer choices Like the glass of a greenhouse, trace amounts of greenhouse gases in the atmosphere are transparent to light energy but block heat transmission back to space. The heat is retained and warms the earth. The greenhouse effect is when the ice caps melt and land that was white (covered by ice) then becomes green. Plants produce oxygen because of the green colored chlorophyll. Their function in the ecosystem is therefore named our green house.