A Punnett square would help here.
Let's say (R) is dominant red and (r) is recessive red, aka yellow.
You start with F1 hybrid flowers that are all (Rr) - these are all <em>orange</em>. So when they reproduce, both parents are (Rr). When you create a Punnett square, you'll see that the results for the F2 generation are (RR), (rr), and (Rr) twice.
(RR) is red, (rr) is yellow, and (Rr) is orange, just like the F1 generation.
Antihistamines are drugs that are used to treat allergic rhinitis (both seasonal and perennial) and other form of allergies that cause hives or urticaria. They can give relief when a patient has nasal congestion, sneezing or hives because of pollen, dust, or animal allergy (allergens). Second generation antihistamines such as loratidine are prescribed for seasonal allergies because they are less sedating than the first generation antihistamines.
C. Because ecosystems consist more of animals
Answer: According to Darwin theory of evolution the struggle for existence is considered as major part for competition among living things.
Explanation:
Coexisting species that belong to the same genera compete for same kind of resources for their survival. Some phenotypic variations gives an survival advantage over others. The superior ones dominate the inferior ones and compete for resources. The one who receives the resources like mates, food, shelter, and others the chances of survival also increases considerably.