Biology 1: Ch.2 Study Guide
What is the maximum number of single covalent bonds a carbon atom can form with other elements?
4
How many protons are in a typical oxygen atom?
8
What is a trace element?
An element that is required in miniscule amounts for life
Which is not one of the four atoms that make up the bulk of living organisms?
Calcium
What are the four classes of large organic molecules important to life on Earth?
Carbohydrates, protein, lipids, and nucleic acids
Why is one side of a single water molecule partially negative while the other side is partially positive?
Electron pairs are unevenly shared between the oxygen atom and the two hydrogen atoms
A needle can be made to "float" on the surface tension of water. What causes this surface tension to form?
The cohesion of water molecules to each other
The majority of the elements essential to life are found in what part of the periodic table?
The top third
Something with a pH of 5 would be
acidic
What are the monomers of proteins?
amino acids
How do buffers minimize change in the pH of biological systems?
by absorbing H+ ions when there is an excess and by donating H+ ions when there is a shortage
Which of the following is a polysaccharide?
cellulose
The bond in which bonded atoms share elements is called an
covalent bond
Individual water molecules are held to one another by relatively weak bonds
hydrogen bonds
If the number of protons in an atom does not match the number of electrons, the atom is specifically called an
ion
What is the sum total of all the chemical reactions that take place in your body called?
metabolism
What is another name for the polymers of carbohydrates?
polysaccharides
To a large extent, a protein's function is dependent upon its shape. What determines a protein's shape?
the sequence of amino acids
What are the ecological consequences of acidification of rain and oceans?
they damage the health of ecosystems
What is the basic structure of typical dietary fats?
A glycerol head and up to three fatty acid tails
What is the most common element in your body?
Oxygen
Water "beads up" on synthetic fabric like polyester but binds to cotton. What is the most likely explanation for this?
Polyester is nonpolar, whereas cotton is polar
