Answer:
<u>d. Transport proteins within the membrane serve as a tunnel for molecules to enter the cell.
</u>
<u />
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>.
Non living things like mountains,oxygen,water.etc
Answer:
Drugged or drunk
Explanation:
if the mother is drugged or drunk because the mother wont be able to comprehend whats going on and may role on the baby and may be very harmful
Answer:
The acidity level of water is measured by the pH scale. Pure water has a pH of 7, which is neutral. However, natural rainwater actually has a pH of 5.6 because it gets exposed to the gases in the atmosphere, making it a bit acidic. True acid rain will have a pH level measuring from 5.0-5.5.
I think its ADP to ATP then NAD+ to NADH