Yes
No oxygen.
Yes, it is possible for an eel to drown. Unlike other fish, its gills are unable to obtain enough oxygen to survive. It therefore has to surface for oxygen periodically.
If the water does not contain enough oxygen, yes.
plants drown because their roots have mitochrondia (in them which supply the plant with energy to survive) that need air which they take from the air spaces in the soil. If there are no air spaces the plant cannot obtain oxygen and they 'drown'.
Actually, it is about the same thing, lack of oxygen.
No, drowning typically results in death due to lack of oxygen.
Yes, a roach can drown in water because they breathe through tiny openings on their bodies called spiracles, which can become blocked by water, preventing them from getting oxygen.
Fish use their gills to extract oxygen from the water, the same way that a human uses their lungs to extract oxygen from the air. The difference is that gills are supposed to be underwater, so of course water doesn't prevent them from working, and therefore they can't drown.
Mermaids could be drowned maliciously. Drowning is just suffocation in water. In stories, mermaids breathe air like us, or water like a fish. Fish gills take dissolved oxygen from water, so if there is no oxygen in the water, the fish suffocate. It seems likely then that putting a mermaid in a sealed tank with no vapour exchange to oxygenate the water would cause the mermaid to use up all the available oxygen in the water. She would then suffocate, or drown.
Yes, it is possible to drown a flea in water. Fleas are small insects that breathe through tiny tubes on their bodies, so submerging them in water can prevent them from getting oxygen and lead to drowning.
A fish will not drown in water if it gets a hole in its fin. Lots of fish (like piranhas) nip holes into other fish's fins as a source of food because fins grow back quickly. if he is not swiming properly or just sitting on the bottom of the tank, it can mean he may have an infection... keep an eye on it
Yes you can but only by draining all the oxygen. If the bedbug is in a room, and the oxygen is removed, this will also suffocate any other animals - and people.