The term steroid describes both hormones produced by the body and artificially produced medications that duplicate the action for the naturally
occurring steroids. All of the following describe steroid hormones EXCEPT?
O They bind with receptor proteins in the plasma membrane to trigger cellular
responses.
O They are derived from cholesterol and are lipid soluble.
O They serve as messengers in hormone signaling pathways.
O They are exemplified by testosterone, estrogen and progesterone.

It has been around since 1858 so b. false

Sand and gravel would be the answer

Producers (autotrophs) are in the bottom (first) trophic level, primary consumers are in the second trophic level, secondary consumers are in the third trophic level and tertiary consumers are in the top trophic level. energy moves through the trophic levels when one living organism is being consumed by another. moreover, energy level becomes lower as it moves up the energy pyramid because of it being released as heat. food chain is when there is a single pathway of energy transfer whereas a food web is when there are multiple pathways of energy transfer.