sometimes
Most likely the other will start to rot too.
There was only one mouldy apple at the bottom of the barrel!
When one apple in a barrel of apples is bruised, it gives off a ton of ethanol gas that will ruin the rest of the barrel. There's probably way more science behind it, but that's basically it!
coral the barrell
One on the counter
I'm not sure if this is it but wouldn't it be something like a whole barrel of bad apples ruins one good apple. Again I'm not sure. It is a metaphor one bad person can make a whole group bad so an opposite might be One good person can make a whole group better
A peach is the odd one out because it contains only one seed; all the others have many.
Strawberry. Strawberries grow on the ground (in patches), the others grow on trees.
Mixamatosis is one- it cannot be cured and will have to be vaccinated against it. Basically it rots and destroys the rabbits mind.
Greener is one. There are dozens of others.
One rotten apple releases ethylene gas, which speeds up the ripening process of surrounding apples and causes them to spoil faster. This spoiling process then spreads as the other apples become contaminated with mold and bacteria from the rotten apple.
Its an analogy to human behavior. One tries to get ahead, and the others will crawl over it, bringing it down.