Never.
Hydra is a eukaryotic organism. It is a member of the animal kingdom and its cells contain membrane-bound organelles, including a nucleus.
The cells of eukaryotes will contain a nucleus.
Prokayotic cells belong in people and it keeps them alive. God made us so he made the prokayotic cells too.
Every single type of cell does except bacteria (kingdom monera). Animal, plant, fungus and protists all do. Organisms made up of these cells, cells with a nucleus and organelles are Eukaryotes.
Nuclei do not contain cells, cells contain nuclei (normally, one nucleus per cell).
Plant cells.
Animalia is eukaryotic, meaning its cells have a nucleus enclosed within membranes. This distinguishes it from prokaryotic organisms like bacteria, which lack a nucleus.
This theory is false. Red blood cells do not contain a nucleus.
Yes, plant cells contain a nucleus.
The nucleus
No they don't. Eukaryotic cells are the ones that contain a nucleus. However, just because prokaryote cells don't contain a nucleus, they still contain DNA. It just floats freely in the cytoplasm.
Yes, animal cells - including octopus cells - contain a nucleus.