The game board is made up of 19 hexes, which represents the Virus the players are working together to find a cure for, and thus save humanity.
There is a center hex (A1) where the players' pawns begin in. Then there is a ring of 6 hexes around the center hex (B1-B6). And then there is an outer ring of 12 hexes (C1-C12).
Each Hex has 3 features.
1. Each hex has a designation/label based on where it is on the virus: B4, C11, etc.
2. There is a number of Research icons the player needs to roll in order to research the molecule in that section of the virus.
These icons will be displayed at the top of the hex, and there will be 1 or 2 of them. In game play this means the player must roll 1 or 2 research icons before they can place their pawn in this hex.
3. There is a protein displayed at the bottom of the hex. When a player rolls a biohazard symbol on a die, it locks the die and it can no longer be rolled.
In order to unlock these dice with the biohazard icon, the player must roll the protein displayed on the hex they are currently in. If a player rolls that icon--and doesn't use it to destroy the Molecule--then they can use it to unlock all their biohazard dice.
In this particular hex the player must roll a yellow protein (unique) to unlock any biohazard dice they may have. In another hex they might only have to roll a blue protein (common).
Placing Molecules on Hexes
So at the start of the game--during the setup face--the players draw a face-down molecule token and place it randomly place it face up on an empty virus. They do this until all the hexes--except the center one (A1)--have a molecule.
In the example above it is coincidental that the molecule with B4 label was placed on the B4 Hex. In most cases they will not match. The only time you intentionally place the B4 Molecule on B4 Hex is during the Mutation phase, which happens twice during the game when you place 3 new molecules on the board.