Genesis 8:20

And Noah builded an altar unto the LORD; and took of every clean beast, and of every clean fowl, and offered burnt offerings on the altar.


Note:  Now we see why there were 7 of every clean beast taken into the ark.  The extra's were meant for the sacrifice(s) Noah would perform. (See Genesis 7:2)

Genesis 8:19

Every beast, every creeping thing, and every fowl, [and] whatsoever creepeth upon the earth, after their kinds, went forth out of the ark.

Note:  "After their kinds" means that, there was not two of every sub-species; a horse could've been on the ark, and so a mule, a donkey, a zebra, etc, would've been "kinds" of horses.  Thus, a horse would represent all "kinds" of horses...

Genesis 8:18

And Noah went forth, and his sons, and his wife, and his sons' wives with him:

Genesis 8:17

Bring forth with thee every living thing that [is] with thee, of all flesh, [both] of fowl, and of cattle, and of every creeping thing that creepeth upon the earth; that they may breed abundantly in the earth, and be fruitful, and multiply upon the earth.

Genesis 8:16

Go forth of the ark, thou, and thy wife, and thy sons, and thy sons' wives with thee.