Answer:
Nucleus, Linear Chromosomes, membrane-bounded organelles, golgi apparatus, mitochondria
Step-by-step explanation:
All life forms consists of either prokaryotic cells or eukaryotic cells.
An Eukaryotic cell is a cell which has a nucleus. They are a group of organisms which have a nucleus that is enclosed inside a nuclear envelop. They contains member bound organelles which includes the mitochondria, endoplasmic reticulum and the nucleus. Some of the examples of eukaryotic cells are plants, animals, protists, fungi, etc.
Where as a prokaryotic cells does not contains a nucleus. They do not have a member bound organelles. Prokaryotic are unicellular. Some examples are bacteria, archaea, etc.
In the context, I would look for features such as membrane bounded organelles, mitochondria, nucleus, golgi apparatus, etc. in the new life form that has been discovered in the new planet to identify them as eukaryotic.