Natural selection acts directly on those gene variations for traits or phenotypes.
The phenotype of an organism is the physical characteristic and is determined by the organism's genotype. Natural selection selects the genes that produce a certain phenotype by providing suitable conditions for a certain phenotype.
Yes we have to maintain homeostasis so our bodies have to adapt to Mother Nature
B. One
because an independent variable is something you change. So in a scientific experiment you only change one thing. If you happen to change more than one thing then the test becomes unfair therefore you should repeat and make sure that only one thing is changed this time.
A semipermeable membrane is a type of biological or synthetic, polymeric membrane that will allow certain molecules or ions to pass through it by diffusion—or occasionally by more specialized processes of facilitated diffusion, passive transport or active transport.
The answer is abdominopelvic cavity
Abdomen is divided into four quadrants and nine regions to make diagnosis and examination of a disease easier. Every quadrants/region has a group organ that might be related to the disease. Since liver is normally located in the upper right, it will be less likely to be found on the lower right quadrant/region.