The answer is a. plant cells have cellulose and animal cells don't.
The markers and colored buoys serve as the "traffic signals" that direct boats to safety. Lateral navigation markers and non-lateral markers of the US Aid to navigation System must be learned for all operators. A green-lighted buoy marks the border/edge of the channel on the operators' port (left side) as the boat enters from open sea. The odd number 3 signals your direction and distance in returning from open sea( as the number increases).
