Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

22 Cards in this Set

  • Front
  • Back
Compounds are divided into 2 principal classes. What are they?
inorganic compounds and organic compounds
Inorganic compounds
usually lack carbon and are structurally simple
What are examples of inorganic compounds?
water and many salts, acids, and bases; may have either ionic or covalent bonds
Organic compounds
always contain carbon, usually contain hydrogen, and always have covalent bonds; most are large molecules made up of long chains of carbon atoms
What percentage of the human body is made up of organic compounds?
38 - 43%
True or False?
Water is the most important and abundant inorganic compound in all living systems.
True. Water makes up 55 - 60% of a lean adult's body mass
True or False?
Nearly all the body's chemical reactions occure in a watery medium.
True. Water has many properties that make it an indispensable compound for life: polarity makes it an excellent solvent for other ionic or polar substances -- gives water molecules cohesion, allows water to resist temperature changes
What is hydrolysis?
break down by water
What is a solvent?
in a solution, a solvent dissolves another substance called the solute. (usually there is more solvent than solute in a solution)
What causes the versitility of water as a solvent for ionized or polar substances?
its polar covalent bonds and its bent shape, which allows each water molecule to interact with several neighboring ions or molecules
solutes that are charged or contain polar covalent bonds; they dissolbe easily in water
Name examples of hydrophilic solutes.
sugar and salt
molecules that contain mainly nonpolar covalent bonds; not very water soluble
Name examples of hydrophobic solutes.
animal fats and vegetable oils
How do polar water molecules dissolve salts and polar substances?
When a crystal of sodium chloride is paced in water, the slightly negatife oxygen end (red) of water molecules is attracted to the positive sodium ions (Na+, and the slightly positive hydrogen portions (gray) of water molecules are attracted to the negative chloride ions (Cl-).
decomposition reactions - breaking down large nutrient molecules into smaller molecules by the addition of water
dehydration synthesis reaction
when two smaller molecules join to form a larger molecule - a water molecule is one of the products formed
heat capacity
water's ability to absorb or release a relatively large amount of heat with only a modest change in its own temperature
Why does water have a high heat capacity?
a large number of hydrogen bonds in water - as water absorbs heat energy, some of the energ is used to break hydrogen bonds. Less energy is then left over to increase the motion of water molecules, wich woud increase the water's temperature
How does water's high heat capacity affect the human body?
It lessens the impact of environmental temperature changes, helping to maintain the hoeostasis of body temperature
heat of vaporization
as water evaporates from the surface of the skin, it removes a large quantity of heat, providing an important cooing mechanism.
True or False.
Water is a major component of mucus and other lubricating fluids throughout the body.
True. Lubrication is necessary in the chest and abdomen where internal organs touch and slide over one another; joints where bones, ligaments, and tendons rub against one another; inside the gastrointestinal tract, mucus and other watery secretions moisten foods