The correct answer is option C, that is, the presence of the nuclear membrane.
Cyanobacteria is a phylum of bacteria that attain their energy via the process of photosynthesis, and are the only photosynthetic prokaryotes possessing the tendency to generate oxygen. As a prokaryote, they are devoid of the nuclear membrane.
Euglena refers to a single cell flagellate eukaryote. It comes under the class Euglenoidea. The species of Euglena are witnessed in salt water and in freshwater. Being a eukaryote, they possess nuclear membrane.
At least two parallel channels of communication flow through each lateral geniculate nucleus. One runs through the parvocellular layers and a second runs through the magnocellular layers.
Answer:
External means on the outside, so it can be something like their fur color. Some other features can be number of legs, if they have wings or not, etc.
The property that makes slate most suitable for roofing shingles is that it can be split into thin, flat layers.
This means that the roofs of houses and other buildings can be created from slate in order to cover the tops in the best way possible. Other materials are also often used for this purpose, but slate is one of the most popular ones nowadays because of that property it has.