A: Yes. You probably need some signal conditioning. The explanation in this paper goes on for a bit, but stay with it and you'll understand what you need and why you need it.
Before you make any connections, get the electrical specifications for the analog-to-digital converter (ADC) and for the sensor or sensors in your system. Let's assume the data-acquisition module uses a Maxim Integrated Products MAX197 12-bit ADC. This device can accept eight differential (2-wire) inputs or 16 single-ended (1-wire) inputs. Maxim's specifications show an input impedance of 21 kohms for single-ended inputs and 16 kohms for differential inputs.
Now let's assume your system uses an Analog Devices AD590 temperature sensor in a simple circuit (Figure 1) to produce a 1-mV/K output. The sensor serves as a variable-current source that passes 1 µA per Kelvin (K), or per degree Celsius (°C). The Kelvin scale uses the same increments as the Celsius scale, but it starts at absolute zero: 0K or -273°C. At 0°C, the Kelvin scale reads 273K and at 25°C it reads 298K. The Kelvin symbol does not include a degree mark.