Answer:
<u>d. Transport proteins within the membrane serve as a tunnel for molecules to enter the cell.
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Explanation:
Solutes are typically moved across the cell through either passive or active transport. The cells, surrounded by a bilipid layer or plasma membrane is amphiphlic- its polar, hydrophilic lipid heads face outwards, while their non-polar hydrophobic lipid tails face inwards towards each other.
While lipid-soluble molecules move across the layer easily, it is also difficult for charged and also large molecules to move across its surface, into the cell. Transmembrane channels, <u>embedded within the membrane</u>, help to maintain selective permeability as transport proteins, pores and gated channels. Simple diffusion happens as a method of passive transport in cells through plasma membranes.
The solutes travel through the plasma membrane in the process of diffusion from regions of high concentration to regions of low concentration; this occurs without the use of energy. <u>Molecules moving against their concentration require active transport mechanism to cross the membrane</u>.
Answer:
cells is the one of element
Answer:
The answer to your question is: Active transportation
Explanation:
Cell can move molecules in or out of it by two processes: Active or Passive transport.
Active transport: is the movement of molecules against a concentration gradient. Use proteins or enzymes to happen.
Passive transport: is the movement of molecules or ions from a higher concentration to a lower concentration.
The cerebrum is a large part of the brain containing the cerebral cortex it lies either in front or on top of the brainstem
