DEPENDS
yes
Yes, a neutered male dog will not have as strong a scent and there won't be as much testosterone in the marking urine.
Why are you smelling dog urine, new hobby or something?
Not unless you inhale the urine itself.
The male knows when the female is ready to mate because when she is in heat there is always a strong scent she lets off and it's carried in her urine, by peeing on the lawn or on the fence males can smell a female on heat by her urine. That is also why whenever dogs meet they sniff each others hindquaters as to find out gender and weither or not they're ready to mate.
I love
Because the dog rolled in it.
Water the yard, urine will dilute and dissipate into the soil.
Dude, if your dog is licking your rug, I suggest you feed it.
That's the smell of urea, which is a nitrogenous end product and therefore, a waste. This, mixed with water, is what forms urine.
Two male dogs will compete for a female in heat because they want the right to mate with her. They will often fight to the death to make sure the other dog does not father the puppies. When a female is in heat, the males will become agitated when they see another male dog.
Try a special enzymatic dog urine remover (available at any pet store). They work the best.