Eighty experiments were conducted in such categories as motion sickness, reproduction and regeneration, immunology, and readaption to a normal gravity environment. A number of different biological specimens were used, including rodents.
The joint U.S./U.S.S.R. experiments were conducted on 2 rhesus monkeys and 10 male Wistar rats. The biological payload also included cell cultures (Escherichia coli). The prime occupants were two macaque monkeys. The 2.3m diameter descent sphere was successfully recovered after 14 days, but a failure in the thermal control system resulted in the deaths of some of the specimens.
Payloads are separated by bullets ( · ), launches by pipes ( | ). Manned flights are indicated in bold text. Uncatalogued launch failures are listed in italics. Payloads deployed from other spacecraft are denoted in (brackets).