3.1 Food Becomes Us Flashcards
What are the most abundant elements in our bodies?
Carbon, hydrogen, oxygen, and nitrogen
What is the chemistry of all life on Earth based on?
Organic molecules - those which contain carbon bonded to hydrogen
Which nutrient classes are made of organic molecules? Which are not?
- carbohydrates, lipids, proteins, and vitamins are made up of organic molecules
- water and minerals are inorganic nutrients because they do not contain carbon-hydrogen bonds
What are atoms?
The smallest units of an element that still retain the properties of that element.
What are elements?
Substances that cannot be broken down into products with different properties.
What are chemical bonds?
Forces that hold atoms together.
What are molecules?
Units of two or more atoms of the same or different elements bonded together.
What are cells?
The basic structural and functional units of plant and animal life.
What are organs?
Discrete structures composed of more than one tissue that perform a specialized function.
Describe the organization of life.
What is digestion?
The process of breaking food into components small enough to be absorbed into the body.
What is absorption?
The process of taking substances into the interior of the body.
What types of tissue does the human body contain?
Muscle, nerve, epithelial, and connective
Do most organs function alone?
No, they are part of a group of co-operative organs called an organ system.
What are the organ systems in humans?
There are 11 organ systems in humans: nervous, respiratory, urinary, reproductive, cardiovascular, lymphatic/immune, muscular, skeletal, endocrine, integumentary, and digestive.
Describe the nervous system.
What are the two main functions of the digestive system?
Digestion and Absorption
Why is digestion important?
Most food must be digested in order for the nutrients it contains to be absorbed into the body.
What is the main part of the digestive system?
the gastrointestinal tract, gut, digestive tract, intestinal tract, or alimentary canal.
Describe the gastrointestinal tract.
hollow tube, 10 meters in length, from mouth to anus.
What are the organs of the gastrointestinal tract?
The mouth, pharynx, esophagus, stomach, small intestine, large intestine, and anus.
What counts as food being “inside” the body?
The inside of the tube that the organs of the gastrointestinal tract form are called the lumen. Food that is still inside the “lumen” is technically still outside the body. Food that has been transferred into the cells that line the intestine by the process of absorption is actually “inside” the body.
What is the pharynx?
Swallows chewed food mixed with saliva.
What is the esophagus?
Moves food to the stomach.
What does the stomach do?
churns and mixes food; secretes acid and a protein-digesting enzyme
What does the liver do?
makes bile, which aids in the digestion and absorption of fat
What does the pancreas do?
releases bicarbonate to neutralize intestinal contents; produces enzymes that digest carbohydrates, protein and fat
What does the gallbladder do?
stores bile and releases it into the small intestine when needed.
What does the small intestine do?
completes digestion; absorbs nutrients into blood or lymph