7.6A Chemical and Physical changes (enzymes)

When you chew a piece of food, your salivary glands release saliva to moisten the food allowing you to swallow the consumed food for the next step of digestion. Additionally, saliva has enzymes that begin to breakdown the starches within the food into smaller molecular components called glucose. What kind of change results from the breakdown of starch into glucose by saliva?

• mechanical

• physical

• chemical

• cyclical

Tags

NGSS.MS-PS1-2

What change occurs to food by your teeth as you chew?

• physical changes only

• chemical changes only

• both physical and chemical changes

• neither physical nor chemical change

Which step in the digestive process represents a chemical change in food?

• storing of swallowed food in the stomach

• muscles that line the stomach mixing the consumed food and liquids

• moving the food down the esophagus and into the stomach

• enzymes within the small intestines breaking down the food into smaller molecules

Your stomach digests a yummy cookie with enzymes. Is this chemical or physical digestion? Is it both?

• physical

• chemical

• both

Which of the following is a chemical change that occurs to the food?

• The reduction in size of food particles as food is chewed

• The movement of food to the stomach after food is swallowed

• The breakdown of molecules of food by enzymes and acid in the stomach

• None of the above

Tags

NGSS.MS-LS1-2

Researchers are investigating processes that happen during digestion. Which answer choice describes only a physical change during digestion?

• Hydrochloric acid in the stomach breaks down proteins

• Chewing in the mouth breaks food into small pieces

• Enzymes in saliva start the digestion of starches before food is swallowed

• Bacteria in the intestines convert dietary fiber into fats

A change in the shape of a substance

• chemical change

• Physical change

• Chemical Change

• Precipitate

A transformation of one substance into another substance

• Chemical change

• Physical change

• Chemical Reaction

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Results in a chemical change and the formation of a new substance

• Chemical change

• Physical change

• Chemical reaction

• Precipitate

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Evidence of a chemical change

• Chemical change

• Physical change

• Chemical reaction

• Precipitate

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5