Answer:
Wetland reduction has caused a decrease in the absorption zones for excess water. If the excess water cannot be absorbed by the soil, it increases the incidence and magnitude of flooding.
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.
The antigen-binding sites of an antibody molecule are formed from the molecule's variable regions which are described as so because their amino acid sequences can be different on different antibodies.
The specificity of antibodies is determined by the variable regions found at their endpoints. Antibodies are specialized proteins secreted by B-cells of the immune system. They are also called immunoglobulins. They contain four polypeptide chains that comprise two heavy chains and two light chains to form a Y-shaped molecule.
The variable regions, more specifically the hypervariable regions of an antibody, have a high ratio of different amino acids with the most common amino acids provided in one place. The variable region serves as the antigen-binding site while the constant region found below the variable region is determined to invade the antigen.
Antibodies are preserved in our body to identify the antigen the next time it encounters. They send the signals to the other body parts to reject the antigen and invade it.
To know more about variable regions of antibodies, refer to the following link:
brainly.com/question/17439586
#SPJ4
Fossil fuels are hydrocarbons, primarily coal, fuel oil or natural gas, formed from the remains of dead plants and animals.
In common dialogue, the term fossil fuel also includes hydrocarbon-containing natural resources that are not derived from animal or plant sources.
These are sometimes known instead as mineral fuels.
The utilization of fossil fuels has enabled large-scale industrial development and largely supplanted water-driven mills, as well as the combustion of wood or peat for heat.
Fossil fuel is a general term for buried combustible geologic deposits of organic materials, formed from decayed plants and animals that have been converted to crude oil, coal, natural gas, or heavy oils by exposure to heat and pressure in the earth's crust over hundreds of millions of years.
The burning of fossil fuels by humans is the largest source of emissions of carbon dioxide, which is one of the greenhouse gases that allows radiative forcing and contributes to global warming.
A small portion of hydrocarbon-based fuels are biofuels derived from atmospheric carbon dioxide, and thus do not increase the net amount of carbon dioxide in the atmosphere.
