False
Not always, some proteins are used in a variety. <span>Protein channels are needed to transport substances because it accelerates the transport process. Very few substances enter or leave cells without being attached to a transport protein. Different types of substances require different types of proteins to transport them. Protein channels transport water or ions downwards and ATP-powered pumps transport molecules or ions upwards. ATP generates energy to transport the molecules upwards. </span>
Natural selection only occurs when there is a superiority within a species set. If there is no genetic variation, no single animal is any better than the next, making the presence of superiority impossible and survival left up to chance. In this case it would be considered genetic continuity.
Because b appears to be an intrusion, the answer should be A.
Explanation:
To raise the temperature of the flight muscles high enough to enable flight the bumblebee shivers, rather the same a we do when we are cold. This can easily be seen in a grounded bee as her abdomen will pump to ventilate the flight muscles.
Answer: layer c is oldest but I can see all of the options
Explanation:
