All but one of the following is a function of the low ph found in the stomach. select the description below that does not reflect a role of stomach acid.
a) the stomach's acid catabolically breaks down food stuffs in preparation for absorption. b) stomach acid denatures proteins making the poly peptide chain more accessible to pepsin digestive enzymes. c) many potentially harmful bacteria will be prevented entry to the small intestine by stomach acid. d) low ph converts pepsinogen to its active form of pepsin, preventing the protease enzyme from digesting the cells that produce it.

Option (A).

Explanation:

Stomach is an important organ involved in digestion that helps in the breakdown of biomolecules. Stomach contains the acidic environment that are necessary for the enzyme activation.

The stomach's acid is not involved in the catabolic breakdown of food stuff. The stomach's acid is also not involved in the food absorption. The acid is used for pepsin digestive enzymes.

Thus, the correct answer is option (A).

vanderwaal's forces of attraction are the electrostatic intermolecular forces that exist in a molecule due to the temporary or permanent dipoles that are developed in a molecule. in , the major intermolecular forces are dipole-dipole interactions as the molecule is polar (bent structure). so the vanderwaal's forces of interaction in between molecules are the permanent dipole-dipole interactions that develop due to the dipole that exists in between the polar h - s bond. the positively charged hydrogen atom is attracted towards the negative end of the dipole that is sulfur of the adjacent molecule. therefore, these forces of attraction are relatively stronger than that of london dispersion forces that exist in non polar molecules.

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.