Identify the meaning of the underlined word in the following sentence: The culling of the cows was done as a means of preventing the spread of BSE
a.
process that determines which animals in a herd will not be bred
c.
The process of separating the herd by male and female
b.
taking blood samples from the cows
d.
all of the above

Animal bodies (and even plant bodies for that matter) are complex enough that life couldn't exist without enzymes. enzymes are usually large, complex biological catalysts that are expensive to make. enzymes speed up the rate of chemical reactions without being used up during the reaction (they can be reused many times). they are highly specific in the reactions they regulate. knowing what enzymes are and how they function, why does this explain why complex life forms could not exist if there were no enzymes.

What does natural resource management aim at ?

Where substance is produced during cellular respiration