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.
Meiosis has two rounds of genetic separation and cellular division while mitosis only has one of each. In meiosis homologous chromosomes separate leading to daughter cells that are not genetically identical. In mitosis the daughter cells are identical to the parent as well as to each other.
Answer:
The correct answer is allopatric speciation.
Explanation:
Allopatric speciation occurs when a geographical barrier comes between a species population living in the same area. This geographical barrier separates the population into two different geographical area which do not have the same condition.
So as both the separated population get different habitat environment to live so they evolve differently from each other. So natural selection and genetic drift works differently in both the population which brings genetic changes in the population and helps in creating a new species.
Answer:
a, b, d, and f.
Explanation:
<em>The periwinkle snails feed on plants. Consequently, they are said to herbivorous and heterotrophic since they cannot manufacture their own foods. They are also referred to as primary consumers because they directly feed on plants without any other nutritional option. They, therefore, occupy the second trophic level on a typical food web. </em>
The correct options are a, b, d, and f.
