Final answer:
Alcohol is absorbed into the bloodstream primarily through the stomach and small intestine, with some initial absorption occurring in the mouth. Nutrient absorption mainly takes place in the small intestine. The metabolism of alcohol involves converting it into acetaldehyde and other substances.
Step-by-step explanation:
The correct statement about the absorption of alcohol into the bloodstream is (b) Alcohol is absorbed into the bloodstream from the stomach and small intestine. While it's true that some substances, like water and salt, can be absorbed through the stomach, alcohol is primarily absorbed through the lining of the stomach and the small intestine. With a small amount of chemical digestion and absorption occurring in the mouth, alcohol quickly enters the bloodstream after consumption due to its ability to permeate the mucous membrane.
Absorption in the digestive system is crucial as it allows nutrient molecules that result from digestion to enter the blood or lymph and be circulated throughout the body. The stomach plays a role in storing food until the small intestine is ready to receive it, regulated by a circular muscle. However, approximately 95% of nutrients are absorbed in the small intestine, particularly in the jejunum, with the exception of certain substances like iron and vitamin B12, which are absorbed in the duodenum and ileum, respectively.
The process of alcohol metabolism involves it being removed from the bloodstream through a series of reactions that convert it into other substances, such as acetaldehyde. This metabolism can vary based on individual factors, including sex, with women metabolizing alcohol more slowly than men on average.