Yellow teeth is a sign of plaque build up, which can lead to dental disease if not treated. It is ideal to start a tooth-cleaning program to get rid of and help reduce any future tartar build up. If the build up is particularly bad, the only way to remove it is for a vet to de-scale your cat's teeth.
If there is only a little plaque, there are many ways to help keep a cat's teeth clean and prevent plaque build up:
Brushing teeth with a pet brush and paste are an active way of keep teeth clean. The best time to introduce a tooth-brushing routine is when they are kittens - it is more difficult to accustom an adult cat to a toothbrush. There are "finger" brushes available also, which is a plastic brush that slips onto a finger. Toothbrushing has to be done every day to be effective.
There are some gels such as Logic Gel that you can either rub onto a cat's teeth directly or mix into food. These gels are said to soften any plaque on the teeth.
The most effective, easiest (and possibly controversial) method is to give your cat raw meat or meaty bones. Chicken wings, necks and chunks of meat (an inch or two thick) help greatly with a cat's jaws and teeth. Meat, even raw meat, is abrasive and the cat has to bite down repeatedly to cut a bite-sized chunk off. This repetative rubbing of the meat against the teeth and gums as the cat chews keeps the teeth clean and massages the gums which helps promote a healthy blood flow. This doesn't need to be fed every day - usually feeding raw meat twice a week is sufficient enough to keep plaque at bay.
A note about dry food:
It has not been proven that dry food cleans a cat's teeth, despite many vets saying otherwise. Kibble is hard and brittle, so it shatters at the tips of the teeth - providing little or no cleaning friction. Dental issues usually start at or under the gum line, so kibble is usually ineffective. Some cats don't even chew; they will just swallow the kibble whole. However, there are some "dental" kibble available which simply means the biscuits are much bigger, but they are still very hard so may offer minimal tooth cleaning.
The dark brown crust in cats noses are caused by dried nasal fluids. These are not harmful and do not indicate any kind of malady.
No.
Cats breathe through their nose.
no but she has one on her nose
Cats may lick your lips as a sign of affection or to show that they are comfortable and trust you. It can also be a way for them to groom you, as they would groom themselves or other cats in their social group.
do you have sunburn? if so this might be why your nose is peeling
I think if your cats nose is cold and wet it means it is healthy, as it being dry not being healthy. But it is not a very big problem since my cats nose is dry sometimes and he is fine.
Cats may lick your lips as a sign of affection or to show that they trust you. Licking can also be a way for cats to groom and bond with their human companions.
Yes, but your ears and nose don't.
upper lips and nose are long and muscular
No. Female cats can be yellow also. I have 5 of them.
lips are the bumpy things below your nose, they are red or pink and inside it there is teeth, the white, bony things. they are the stinky stuff under your nose that not even your mother goes near