Answer: 1/4
Explanation:
Firstly, in order for both parents to be type A and have children with type o blood, their blood types must both be Ao. Since o is a recessive blood type, a punnett square shows there is a 25% chance any child of theirs will have type o blood. If neither parent is color blind and they have a son who is, it implies that the mother is a carrier of colorblindness and has the genotype XᴮXᵇ. If you do a punnett square of the not colorblind father (XᴮY) and the mother, it shows that a daughter would have a 0% chance of being colorblind. Therefore colorblindess is irrelevent, since there is no possibility of the daughter not having normal color vision. In conclusion, there's a 25% chance she will have type o blood and not be colorblind, since the other 75% chance would be having type A blood and not being colorblind.
A because I know it because I have the same test and it was right
The organisms which appeared on earth first was bacteria.
<u>Explanation:</u>
- The first-ever living organism on Earth was a bacteria known as cyanobacteria. It is believed by scientists that it first formed around 3 billion years ago.
- When the Earth was first formed, it was inhospitable for a long time until 3.8 billion years ago approximately, the core cooled down and the level of oxygen had risen. This, along with photosynthesis resulted in the formation of Cyanobacteria.
- These organisms were capable of carrying out the process of photosynthesis by which they prepared their food. These were known as common ancestors. All the living organisms thereafter are known to be their descendants.