25. Endotoxin

21. Net primary production

22. Endemic species (特有種)

23. Alternation of generations

24. Okazaki fragment

三、簡答題26. Briefly describe the two reactions of photosynthesis and the key products of each reaction.

27. Differentiate between DNA and RNA in terms of structure and function.

問答題 1. The human body responds to the introduction of a foreign antigen by initiating the production of antigen-specific antibodies through a mechanism known as "Clonal Selection." This process encompasses a primary response and a secondary response. Please elaborate on the events occurring in each response and provide a comparison of the quantity of antigen-specific antibodies produced during these distinct phases.

2.Please describe an action potential, including the triggering and changes in membrane potential and ionic fluxes across the membrane. If the amplitude of an action potential is lower than normal, what can be going wrong?

3.Please define a "keystone species" and present an example to show how a keystone species affects the biodiversity of a community.

4.Explain the major factors that threaten biodiversity. What is the most effective way to slow down the decrease in marine biodiversity? Why?