Answer:
B. The membrane lets certain substances move across it freely, while others must move through a “gate”.
Explanation:
Selective permeability is a property of cellular membranes that only allows certain molecules to enter or exit the cell. This is important for the cell to maintain its internal order irrespective of the changes to the environment. For example, water, ions, glucose and carbon dioxide may need to be imported or exported from the cell depending on its metabolic activity. Similarly, signaling molecules may need to enter the cell and proteins may need to be released into the extracellular matrix. The presence of a selectively permeable membrane allows the cell to exercise control over the quantum, timing and rate of movement of these molecules.
Answer:
Hydrogen bonding is caused by the tendency of some atoms in molecules to attract electrons more than their accompanying atom. This gives the molecule a permanent dipole moment – it makes it polar – so it acts like a magnet and attracts the opposite end of other polar molecules.
Answer:
Angiosperm
im not sure what this means lol but i remember reading it somewhere
A large class of molecules is called a macromolecule.
Answer:
I believe it is the "Nucleus."
Explanation:
Hope my answer has helped you!