The Bion satellites are built on the basis of the Zenit satellites, themselves derived from the Vostok spacecraft.

Bion has a mass of 6t, can carry 625kg of equipment, and has an operational life in orbit of thirty days. A Bion satellite can be broken down into three parts: the Drop Compartment, the Descent Compartment (SA) and the Instrument Compartment.

Only the SA Compartment is capable of returning to Earth. It contains most of the scientific payload. It is shaped like a sphere 2,3 m in diameter and has two hatches 1,2 m in diameter.

The Instrument Compartment is cylindrical in shape and has a mass of 500kg. It has a diameter of 2m and a length of 50cm. It also contains scientific experiments. The Bion capsules are very similar to the Foton capsules, but have the additional capacity to house small animals.

This mission carries a series of experiments, exclusively Soviet, to study the influence of space flight on living organisms and to test life support systems for biological entities. Particular attention was paid to the structural changes experienced by organisms during orbital flight.