NO, I think that mice can't give themselves a heart attack.
To spare "human lives" because they want to test something "without a heart" because mice have human bodies but no heart, NO because humans are too selfish to test one themselves, the most reliable, mice can be resistant to a disease humans aren't resistant to.
Yes, mice can get heart diseases. In fact, any creature that has a heart can get heart disease. Of course, mice usually do not die from heart disease; they face many other dangers that are likely to kill them before they get old enough to suffer from degenerative disease.
Mice smell much more than rats. They smell if you don't clean their cage every few days! The animals themselves don't usually smell as they clean themselves. Also, you shouldn't do this to mice, but you can give rats bathes, but you can only give them one about once every month. Pet Stores also sell spray that you can apply to mice and/or rats that will help the smell.The oil in their fur will come off if you do.
Racism has long been a problem in the mouse community.
yes they can
No, but they could attack if provoked.
a heart
you don't bath mice.
No. A cratch is a holder for fodder. Mice do SCRATCH, though. They occasionally scratch themselves with their back paws.
Obviously they do. Mice are constantly running around trying to provide food for themselves and even their family.
It depends on what kind of mice you are looking at. Although most common house mice are vegetarians. (Did I spell That right?^)
When they are kittens, definitely. Their mother kills mice and rips the mice to pieces to show the kittens what to do. Later she brings injured live mice to the kittens to teach them to hunt. When they are adults, it will depend on the cat. House cats often will not even eat mice they killed themselves as they were not trained by their mother to do so.