Genesis 7:16

"The animals going in were male and female of every living thing, as God had commanded Noah.  Then the Lord shut him in."  Genesis 7:16

Again, Noah didn't just bring in the male animals or just the female animals, but he brought in both genders of every kind of animal.  It also repeatedly points out that Noah is doing these things just as God commanded him to.  It doesn't tell us how Noah felt about these commands or even if he went about them without grumbling or complaining about them or if he ever questioned God - it only tells us that he obeyed God.

It doesn't matter if we understand what or why God tells us to do something.  Sometimes, like Noah, we can look back and understand how obeying saved us from some calamity.  There are some things that we may never understand in this life, but that doesn't mean that they weren't for our benefit anyway.