Statement-I : All organisms from the prokaryotes to the most complex eukaryotes have the ability to sense their surroundings and respond to environmental stimuli.
Statement-II :Sense organs ar not obligatory to all living systems, however humans have well-developed sense organs.

 The most obvious and technically complicated feature of all living organisms is this ability to sense their surroundings or environment and respond to  environmental stimuli which could be physical, chemical or biological.

All organisms, from the prokaryotes to the most complex eukaryotes can sense and respond to environmental cues.

 Humans sense our environment through our sense organs(well developed). 

But presence of sense organs is not obligatory in all living organisms. 

 Plants respond to external factors like light, water,  temperature, other organisms, pollutants, etc.