Biology 12

Chapter 1 The Chemistry of Life • MHR 31

CHAPTER 1 REVIEW

Summary of Expectations

Briefly explain each of the following points.

• Chemical bonds join atoms to form molecules.
  (1.1)


• The core of every organic molecule contains
  carbon. (1.2)


• Functional groups attach to carbon cores of
  biological molecules and contribute to their
  function. (1.2)


• Acid-base reaction (neutralization) is one of
  the four major biochemical reactions in cells.
  (1.3)


• Redox reactions are important to cellular
  metabolism. A redox reaction involves:
  oxidation (the loss of electrons) and reduction
  (the gain of electrons). (1.3)


• Metabolic processes require a fairly constant
  pH. (1.3)


• Hydrolysis is a reaction that splits
  macromolecules through the addition of a
  water molecule. (1.3)


• Condensation is a reaction that removes water
  from monomers, synthesizing a polymer. (1.3)

Language of Biology

Write a sentence including each of the following

words or terms. Use any six terms in a concept map

to show your understanding of how they are related.

• metabolism • structural isomers


• atom • stereoisomers


• nucleus • functional groups


• protons • macromolecules


• neutrons • monomer


• electrons • polymer


• element • organic acids


• isotopes • organic bases


• valence shell • neutralization


• valence electrons • buffers


• chemical bonds • reduction


• covalent bond • oxidation


• ionic bond • redox reaction


• ion • condensation


• electronegativity • hydrolysis


• non-polar covalent • monosaccharide


• polar covalent • disaccharide


• polar molecule • polysaccharides


• hydrogen bonds • nucleic acid


• hydrophilic • peptide bonds


• hydrophobic • polypeptides


• organic • lipid


• isomers

1.Proteins perform many functions in biological
systems. Identify one protein and its function.

2.A protein is a polymer or chain of sub-units.
(a)What is the subunit of a polymer?
(b)What kind of bond links these subunits
together?

3.Which is smaller, a hydrogen atom or a
hydrogen molecule? Explain briefly.

4.How is a molecule of carbon dioxide different
from a molecule of oxygen gas?

5.Define the word “isotope.”

6.Which part of the atom is most involved in
chemical reactions?

7.What is a valence electron?

8.Describe the structure and function of a
chemical bond.

9.Use examples to explain how an ionic bond is
different from a covalent bond.

10.How does the polarity of water molecules

account for the ability of water to dissolve

many substances?

11. (a)What is a hydrogen bond?
    (b)Identify one case where hydrogen bonds
    are important to a biological system.
    12.Define the terms “hydrophobic” and
    “hydrophilic,” and provide an example of each.
    13.What role do buffers play in a cell?
    14.Identify two isomers of glucose. How are these
    molecules similar? How are these molecules
    different?
    15.How do functional groups change the nature of
    hydrocarbon chains?
    16.What is meant by oxidation?
    17.Define the terms “polymer” and “monomer.”
    Use these terms in a description of
    carbohydrates.
    18.Identify two nucleic acids.

UNDERSTANDING CONCEPTS