Selective toxicity is one of the desired features of a successful chemotherapeutic agent and refers to the ability of the drug to kill or inhibit the pathogen only while not damaging the host organisms or presenting the minimum damage to the host. A drug with selective toxicity normally targets the cellular processes or structures that are pathogen-specific and are not present in the host organisms. For instance, penicillin inhibits the synthesis of peptidoglycan but does not affect the host cell since the animal cells lack cell walls.
The answer is Keystone. Keystone is a species in which others species in the ecosystem largely depend on, if the species was removed the ecosystem would change drastically.
Fats must be broken down into fatty acids before being converted into glucose. Lipids are known as the back up energy source. They are used to make enzymes, hormones, and antibodies.
