Answer:
Because the tongue is a muscle. Muscles can be involuntary(moves without control) or voluntary(controlled). Necessarily, the tongue is not an involuntary muscle, but the tongue not staying still, scientifically, can be a sign of lacking energy.
Answer:
A. Heritable
C. Affected by the MC1R gene
D. Polygenic trait
Has evolved due to evolutionary processes such as natural selection.
Explanation:
Human skin color is a polygenic trait as it is regulated by more than one gene. Each allele of these genes has an additive effect on the overall skin color of an individual. Therefore, the trait is a continuous trait, not a discrete one. The genes for human skin color are transmitted from parents to progeny which in turn makes it a heritable trait.
The gene MC1R codes for melanocortin 1 receptor and thereby, regulate the skin color of humans since melanocyte-stimulating hormone binds to the receptor to trigger the synthesis of melanin from melanocytes. Evolution of various skin color in human beings is regulated by natural selection which in turn favors the skin tone best suited under the prevailing climatic conditions of a particular human population
Answer:
the variable that is being measured
The two skills are understanding blueprints an technical documents and using specialized tools to test products.