Answer:
The phenotypic ratio among phenotypes produced from an F1 X F1 dihybrid cross is 9:3:3:1.
Explanation:
The law of independent assortment is Mendel's fourth postulate which states that alleles of different genes are  independently of one another assorted into gametes during meiosis. So, if we observe two traits, for example pea color (gene A) and pea shape (gene B), the alleles A and a will separate independently of alleles B and b. Mendel has shown in his experiments (with dihybrids-heterozygous for both genes e.g. AaBb) that there are four different categories with the phenotypic ratio 9:3:3:1.
Food chains are usually short mainly because A) only a single species of herbivore feeds on each plant species. B) local extinction of a species causes the extinction of the other species in its food chain. C) most of the energy in a trophic level is lost as it passes to the next higher level. D) predator species are less diverse and less abundant than prey species. E) most producers are inedible.
Answer:a
Explanation:because the other ones don’t make sense
The primary reason for the brevity of food chains is due to substantial energy loss at each trophic level. This energy loss limits the number of viable trophic levels within a given food chain, making them usually short. Food webs better illustrate this complexity, as they factor in organisms feeding on multiple trophic levels.
Explanation:Food chains are often limited in length due to the loss of energy at each trophic level. In essence, most of the energy within a given tier is lost as it moves to the next higher level, which is a consequence of the second law of thermodynamics. So, essentially, after several trophic energy transfers, the quantity of energy left might not be sufficient to sustain viable populations at an even higher trophic level, making food chains usually short. This is evident in the complexity of food webs, where organisms feed on or can be fed on from multiple trophic levels, creating a complex network of energy transfers that isn't purely linear like a food chain.
For example, in a typical food chain, primary producers like plants generate energy via photosynthesis. Herbivores, or primary consumers, then eat these plants, and carnivores, or secondary consumers, eat the herbivores. Each time energy is transferred to the next level, a significant portion is lost, primarily as heat, limiting the number of viable levels in the food chain.
Learn more about Energy Loss in Food Chains here:https://brainly.com/question/26094710
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