The geological features were different. And humans development was different.
Answer:
A step that is not part of natural selection is people select which individuals breed and which ones do not.
Explanation:
Natural selection is a process in which favorable or unfavorable environmental conditions determine the evolution of species, producing differences in their genotype over a long period of time.
As its name indicates, it is a natural selection, in which no intervention by people is contemplated, so that <u>people cannot determine which individuals breed</u>.
Natural selection implies that the characteristics on which the environment influences are inheritable, that there is genetic variability in the population and that the variability of these characteristics implies the ease of reproduction and survival capacity.
<em>The other options do form part of natural selection, since they are based on the three premises of this process:
</em>
- <em>Inheritable characteristics.
</em>
- <em>Genetic variability.
</em>
- <em>The variability of characteristics influences reproduction and survival.</em>
<span>cardiorespiratory endurance and muscular strength</span>
Answer:
The voltage-gated potassium channels associated with an action potential provide an example of what type of membrane transport?
A. Simple diffusion.
B.<u> Facilitated diffusion.
</u>
C. Coupled transport.
D. Active transport.
You are studying the entry of a small molecule into red blood cells. You determine the rate of movement across the membrane under a variety of conditions and make the following observations:
i. The molecules can move across the membrane in either direction.
ii. The molecules always move down their concentration gradient.
iii. No energy source is required for the molecules to move across the membrane.
iv. As the difference in concentration across the membrane increases, the rate of transport reaches a maximum.
The mechanism used to get this molecule across the membrane is most likely:
A. simple diffusion.
<u>B. facilitated diffusion.
</u>
C. active transport.
D. There is not enough information to determine a mechanism.
Carrier proteins - exist in two conformations, altered by high affinity binding of the transported molecule. Moves material in either direction, down concentration gradient (facilitated diffusion). EXAMPLE: GluT1 erythrocyte glucose transporter.
Channel proteins - primarily for ion transport. Form an aqueous pore through the lipid bilayer. May be gated. Moves material in either direction, down concentration gradient (facilitated diffusion). EXAMPLES: Voltage-gated sodium channel, erytrhocyte bicarbonate exchange protein.
This might be helpful... because I don't know anything about facilitated diffusion.
