Answer:
CO2 and N2 movement in and out of cells is unaffected when membrane protein activity is blocked.
Explanation:
The selective permeability of the biological membranes, like a cell membrane, to small molecules, allows the cell to control and maintain its internal composition.Free diffusion across the lipid bilayer can happen only for small uncharged or nonpolar molecules, such as CO2 and N2. Thus, they can easily cross cell membranes, without the assistance of the transmembrane proteins. Small uncharged polar molecules, such as H2O, also can diffuse through membranes without any help from channel proteins or carrier proteins, which are the two types of transmembrane proteins.
In the case of molecules like glucose, passage across the membrane occurs via the action of specific transmembrane proteins, which act as transporters. These transmembrane proteins allow polar or charged molecules to cross the membrane through a protein pore without interacting with the hydrophobic fatty acid chains of membrane phospholipids.
Answer:
Most hormone feed back is a negative feed back mechansm, A feed back mechanism is a form of a signal mechanism loop where product feed back to control its own production.
Explanation:
For example pancreas is an important gland in an endocrine system which relies on negative feed back to regulate blood glucose level in the body to keep it within the required healthy range.
Answer:
D
Explanation:
Absolute age is defined as the numeric age of fossils.
To identify the absolute age of a fossil, the amount of certain radioactive elements in the rock are measured. When fossils are formed in the rocks, a small amounts of radioactive elements is included in it. The process to identify age of fossil using radioactive elements is known radiometric dating. So, radioactive isotope and its decay product gives absolute age of fossils.
Hence, the correct answer is "D".
The most obvious way we can establish and maintain a healthy coastal ecosystem is by recycling all recyclable materials and trying to live with as little waste as possible. Also, using clean transportation, such as biking and such, would help slow down air pollution; giving sealife clean air to breathe.
Here is the answer of the given question above.
Often times, non-human life in an urban ecosystem is more disturbed in a way that changes happen rapidly, such as the soil and plant cover and temperature and water availability. In this kind of ecosystem, there is no stability and sustainability. On the other hand, in an undeveloped forest ecosystem, plants play a major role and that, the lives in this kind of ecosystem is undisturbed, making it more ideal for many animals to live. Hope this answer helps.