Answer:
1 I think, read the explanation.
Explanation:
Offspring need to carry just one dominant allele from their parents to inherit the polydactyl condition. The probability of the offspring having polydactyly is 50% (2 of the 4) and 50% not having it (normal). This can be expressed as a ratio, 2:2 which can be simplified to 1:1. - found on the internet
Answer:
here.
Explanation:
Due to the prevalence of malaria in Africa, the allele for sickle cell anemia (HbS) provides a selective advantage. That's why it remains in the population.
A normal African person (HbAHbA), with normal haemoglobin, will not die of anemia, but will die of malaria.
An African person with sickle cell anemia (HbSHbS), with abnormal haemoglobin, will die of anemia.
A heterozygous African person (HbAHbS), with half of his red blood cells (RBCs) being normal and the other half being sickle-shaped, will neither die from anemia, nor malaria since the plasmodium will be incapable of completing its life cycle in the abnormal RBCs.
Thus heterozygous African people will grow, reproduce and pass on the HbS allele to the next generations.
Answer: Sea walnuts are marine invertebrates. They belong to the genus Mnemiopsis.
Explanation:
These animals have stinging tentacles like jelly fish and they often cast up or come to the sea shores where if they come in contact with humans can harm them by stinging.
The barrier if kept along the side of the sea shore and not allowing humans to reach to the shore can help in preventing the harm from these animals. The introduction of the predatory animals in the sea can also help in reducing their population.
The three benefits for removing the sea walnut:
1. The population of other species will increase as sea walnut is an invasive species.
2. The balance of the marine ecosystem can be maintained.
3. Humans can be protected from the harm caused by these animals.
