Answer:
In a cross between two black-haired guinea pigs, 20 offspring are born. If both parents were heterozygous, probability would predict that approximately 1 out of 20 offspring would have brown hair
Explanation:
The two parents crossed were heterozygous dominant black coat color, after crossing 75% gives dominant black color coat while 25% gives only brown coat color homozygous
Answer:
Replication, transcription, translation (it’s the central dogma of biology)
Yes most of them do. That is one of the main reasons why dogs get spayed/neutered. In order to give birth, You need to of had your period first. So the animals that can give birth have a period. I don't know how long it is though. I am also not sure about fish, just mammals.