Answer:
The correct statement concerning the cell membrane lipid molecules is that "energy is not expended during diffusion" (Option d)
Explanation:
Biological membranes are formed by two lipidic layers arranged with their hydrophilic polar heads facing the exterior and the interior of the cells, and their hydrophobic tails against each other. Membranes are fluid, which means that molecules that form it have the capability to move through it.
Lipids can easily change places with other neighbor lipids by <u>lateral diffusion</u> in the same layer. This is passive diffusion, which means that it does not need energy to happen.
Lipids can also diffuse transversally to the other layer, but this kind of movement is not as easy as lateral diffusion.
There are also other lipidic movements as rotational diffusion that imply the rotation of the molecule.
Through this lipidic bilayer, there is also a passive transport of some particles from one side of the cell to the other which happens because of concentration differences.
Polar molecules i believe
Maintaining acidity- <span>In case the pH in the environment drops a lot (becomes very acidic), there is a flux of H ions from the cell's cytoplasm into the cell's vacuole thereby increasing acidity to required level and thus maintaining the </span><span>specific pH </span><span>in the cells internal environment as well.
Turgidity- </span><span>Vacuoles regulate the turgidity by regulating the amount of water inside the cell. </span>
cell has excessive water:<span> vacuole absorbs the water and then diffuses it out of the cell.</span>
cell lacks water<span>: water from the vacuole gets passed back into the cell thereby maintaining turgidity.
And here's a video </span>https://youtu.be/3tqjITi8S8s
The plant cell has a cell wall, chloroplasts, plastids, and a central vacuole—structures not found in animal cells. Plant cells do not have lysosomes or centrosomes.
The tiger shark is a keystone species or apex species that thrives in warm waters. The extinction of these sharks would result in the spread of certain algae to the point in which they become an invasive species. It would also result in species of smaller populations going extinct due to a possible increase in the predators that would have been otherwise controlled by tiger sharks.
hope that helped!