Caffeine works as an adenosine receptor antagonists, this essentially means that it works in the opposite manner or works against the receptor. Think of antagonist in the term of literature it goes against the agonist. Adenosine when bond to the receptor causes tiredness, this is the reason why people drink caffeine to stay wake and to prevent cognitive decline from exhaustion. So caffeine doesn’t really effect learning or memory to a large extent like other stimulants do. So basically caffeine increases wakefulness which in turn allows a person to focus longer, slight increase in memory, and more of a sorted out thought process.
Answer: B. The bacteria must adjust to the nutrient content in the new medium, synthesizing necessary amino acids, growth factors, and enzymes.
Explanation: The lag phase is a time for adjustement to new environments, in this case new mediums. In that phase, bacteria sense the available nutrients to synthesize those required and grow as preparing for division, metabolizing to produce energy, making proteins, fatty acids, etc.
<span>The answer is b. chemical
hope this helps!!!</span>