Answer:
A polygenic trait can be described as a physical trait which is influenced by more than one gene.
The three types of selection for a polygenic trait are:
1) Directional Selection: In a directional selection, one of the phenotype is favored in an ecosystem. As a result of this favoring, the allelic frequency changes and shifts in favor of this particular trait.
2) Stabilizing selection: It is a type of natural selection in which the intermediate trait is favored. The population carries a middle trait in abundance.
3) Disruptive Selection: Disruptive trait is a type of natural selection in which the traits on the extreme sides are favored. The intermediate traits are less favored.
The initial assessment of bats suggested they lacked the ability to synthesize vitamin C (Birney, Jenness, and Ayaz 1976). However, several recent studies have shown that approximately two thirds of different bat species have functionally expressed GULO genes (Cui et al. 2011a; Cui et al. 2011b). The various bat taxon taxa that lack the ability to make vitamin C have varying levels of deletion degradation in their GULOgenes and the patterns of sequence variation show that they are lineage independent events. Trying to explain the discontinuous GULO deletion patterns within a common descent paradigm has produced a variety of difficult contradictions for a coherent model of bat<span> evolution </span>(Cui et al. 2011b).
Loss of vitamin C pathway function and GULO gene degradation has also been detected in guinea pigs, great apes, and humans (Lachapelle and Drouin 2011; Nishikimi, Kawai, and Yagi 1992; Nishikimi et al. 1994; Ohta and Nishikimi 1999). In addition, naturally occurring scurvy and osteogenic disease pathologies related to GULO inactivating mutations and large-scale deletions have been documented in rats, mice, and pigs (Harris et al. 2005; Hasan et al. 2004; Jiao et al. 2005; Kawai et al. 1992; Mohan et al. 2005). Thus, degradation of the GULO gene in a wide array of mammals and birds is a relatively common occurrence.
Uring this period he became acquainted with Osama bin Laden, a wealthy Saudi who had joined the Afghan resistance to the Soviets,
Answer:
Weight and skin color.
You can be born with a different skin color and it can change according to the place you live in. Suppose you were born in Alaska and moved to Mexico, your skin color would become darker as you will receive more vitamin D. You body structure to will also be based on your parents. If your parents are fat but you exercise and eat healthy your body structure will change.
Leaves are the food factories for plants they grow quickly, there are so many of them, and are they easily replaced.
