Answer:
Both facilitated diffusion and active transport are selective processes. Only selective molecules are allowed to cross the membrane. They utilize carrier proteins to move across the membrane.
Explanation:
Diffusion is the process by which molecules move across a membrane respective of the concentration gradient. The plasma membrane is a <em>selectively permeable membrane</em> which allows specific molecules to move across the concentration gradient.
Molecules migrate from a region of higher concentration to a lower concentration in case of diffusion. It can be classified into simple diffusion and facilitated diffusion. These are examples of <em>passive transport</em>.
In facilitated diffusion molecules move across the concentration gradient with the help of <em>carrier proteins or channel proteins</em>. The carrier proteins bind to the molecule which has to be transported and change conformation to allow it to cross the membrane. For example glucose molecule is carried across through <em>GLUT transporter</em>. <em>Channel proteins</em> open a channel inside the membrane and molecules get transported across the gradient.
Active transport carries molecules against the concentration gradient with the assist of energy. ATP hydrolysis is utilized to generate energy. As a result of active transport, the molecules are aggregated on one side of the membrane.
Energy from ATP causes a transport protein to change shape, binding substances on one <span>side of the membrane, and releasing them on the other.</span>
Answer:
2.Less than 73% of the populations would have only one allele present.
Explanation:
The two alleles chosen do not affect the fitness of flies in the lab environment, so Kerr and Wright could be confident that if changes in the frequency of normal and forked phenotypes occurred, they would not be due to natural selection.
Using a larger breeding population would not be expected to alter the outcome of the experiment.
Adenine pairs with thymine (or uracil), and guanine pairs with cytosine.
Answer:
D. "Even a moderate dose of THC can produce perceptual distortions and coma"