Well there are many catastrophic scenarios that we already overcome. You should consider educating yourself about the great filter. A great filter is a hypothetical barrier that each civilization can or cannot overcome. From here on things get a little complex so I won't bore you with them. But there are experts in this theory called great filter and I'm sure they can tell you a lot about.
The correct answer is option (B) lemon juice.
pH refers to the logarithmic scale used to indicate the acidity or basicity of an aqueous solution. It is the negative of the base 10 logarithm of the activity of the hydrogen ion. Solutions with a pH less that 7 are considered acidic and the solutions with a pH greater that 7 are considered to be basic. A pH of 7 is neither an acid nor a base and is considered neutral.
An acid has a high concentration of hydrogen ions (H+) and a base has a low concentration of hydrogen ions. Higher the hydrogen ion concentration, pH is acidic. Among the given substances, lemon juice has a pH of 2, urine has a pH of 6, tomato juice has a pH of 4 and black coffee has a pH of 5. Since lemon juice has a pH of 2, it has the lowest –OH ion concentration.
Answer:1,3,4
Explanation:
Antibiotics, Antiparasitic, Antifungal
230 is your anwser! sorry bad english
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.
