Biology help please?

Question

1. How do man's teeth indicate that he is an omnivorous animal?

2. What are the special functions the stomach performs?

3.Describe the mechanics of digestion as food passes through man's digestive system.

Answer 1

1) Man has incisors (for biting), Canine teeth for tearing (eg meat) and molars for grinding hard stuff. Most carnivores have enlarged canine teeth, while most herbivores have no canine teeth: if you imagine a horse, it has incisors and molars only. Man has retained a complement of teeth types suitable for eating anything he likes.

2) the stomach secretes proteases (such as pepsin) to break down food proteins to peptides/amino acids. The stomach is a very acidic (necessary for pepsin to function), cells in the stomach lining secrete hydrochloric acid into the stomach to maintain a low pH. mucus protects the stomach from the actions of pepsin and acid (as it is basically a bag made of protein itself)

The stomach is also responsible for removing a lot of the water from the food along with soluble compounds such as salt and alcohol.

3) Look on wikipedia this would be very long winded to explain. Search "digestion".

Answer 2

1. He should have both incisors for grabbing and tearing, and molars for grinding.

2. Stomach begins digestion in the highly acidic environment that begins the breakdown of large molecules into smaller ones for further digestion in the intestines. It is also important to absorption of the vitamin B12, water, and some ions.

3. The mechanics or the chemistry? Mechanistically, you're referring to the physical phenomenon such as chewing/grinding, muscular contractions, and stomach churning. However, in a larger scheme, food is ground up by the teeth in the mouth, then moved down the esophagus by peristalsis (series of muscular contractions) to the stomach, which churns it a bit and breaks it down with stomach acid. Then it moves into the small intestine, passing by the gall bladder which secretes bile to help digest fats, then the pancreas, which helps to neutralize stomach acid, then on down through the intestine, where enzymes help digest sugars. Most nutrients are absorbed in the small intestine. Then it moves on into the large intestine, where water is absorbed and the indigestible fiber, etc., is stored until the body evacuates it in the form of feces.

Answer 3

the canines