Agonist/antagonist
Agonist are drugs that bind and activate a receptor with effecting the response.If the effect results in maximum response it is considered as full agonist. However if the drug that binds to the receptor results only into partial efficacy in relation to the full activation of the receptor, this is considered as partial agonist.
Antagonist are drugs that blocks a biologic response of a hormone or another drug. They usually have affinity to the receptors but has no efficacy. This drug will just inhibit the activation of the receptors by the aganist.
Answer:
Food - Cow & Rabbit
Fiber - Alpaca & Camel
Work - Donkey & Horse
By-products- Cow & Sheep
Research - Monkeys & Rats
Entertainment - Dogs, Cats, Hamsters ect.
Answer:
Different numbers of neutrons
The answer to this is the last option i think