Questions

Eukaryotic cells contain membrane-bound organelles, including a nucleus. Eukaryotes can be single-celled or multi-celled, such as you, me, plants, fungi, and insects.

Whereas Prokaryotic cells do not contain a nucleus or any other membrane-bound organelle. Bacteria are an example of prokaryotes.

From the given options, Though is the only word which gives sense for the sentence. Hence, Though pompous he was an entertaining person.

Here from the above options, Algae is an Autotroph.

Autotrophs : 

An Autotroph is also called as Producer, is an organism that produces complex organic compounds from simple substances present in its surroundings, generally using energy from light or inorganic chemical reactions.

Mixed heart means the heart in which the oxygenated and the deoxygenated blood is mixed. Reptiles and amphibians have mixed heart.