Anatomy & Physiology 02 Chemical Organization


Access: Public Instant Grading

Start FlashCards Download PDF Quiz Series Learn

Get the best Anatomy & Physiology course in your pocket!

Human dna

This figure shows a double helix.
Human DNA is described as a double helix that resembles a molecular spiral staircase. In humans the DNA is organized into 46 chromosomes.

Chapter objectives

After studying this chapter, you will be able to:

  • Describe the fundamental composition of matter
  • Identify the three subatomic particles
  • Identify the four most abundant elements in the body
  • Explain the relationship between an atom’s number of electrons and its relative stability
  • Distinguish between ionic bonds, covalent bonds, and hydrogen bonds
  • Explain how energy is invested, stored, and released via chemical reactions, particularly those reactions that are critical to life
  • Explain the importance of the inorganic compounds that contribute to life, such as water, salts, acids, and bases
  • Compare and contrast the four important classes of organic (carbon-based) compounds—proteins, carbohydrates, lipids and nucleic acids—according to their composition and functional importance to human life

The smallest, most fundamental material components of the human body are basic chemical elements. In fact, chemicals called nucleotide bases are the foundation of the genetic code with the instructions on how to build and maintain the human body from conception through old age. There are about three billion of these base pairs in human DNA.

Human chemistry includes organic molecules (carbon-based) and biochemicals (those produced by the body). Human chemistry also includes elements. In fact, life cannot exist without many of the elements that are part of the earth. All of the elements that contribute to chemical reactions, to the transformation of energy, and to electrical activity and muscle contraction—elements that include phosphorus, carbon, sodium, and calcium, to name a few—originated in stars.

These elements, in turn, can form both the inorganic and organic chemical compounds important to life, including, for example, water, glucose, and proteins. This chapter begins by examining elements and how the structures of atoms, the basic units of matter, determine the characteristics of elements by the number of protons, neutrons, and electrons in the atoms. The chapter then builds the framework of life from there.

Quiz PDF eBook: 
Anatomy & Physiology 02 Chemical Organization
Download Chemical Organization Quiz PDF eBook
29 Pages
English US
Educational Materials

Sample Questions from the Anatomy & Physiology 02 Chemical Organization Quiz

Question: The smallest unit of an element that still retains the distinctive behavior of that element is an ________.




elemental particle


Question: Which of the following is a molecule, but not a compound?






Question: When an atom donates an electron to another atom, it becomes


an ion

an anion


all of the above

Question: A substance formed of crystals of equal numbers of cations and anions held together by ionic bonds is called a(n) ________.


noble gas




Question: The energy stored in a foot of snow on a steep roof is ________.


potential energy

kinetic energy

radiant energy

activation energy

Question: A molecule of ammonia contains one atom of nitrogen and three atoms of hydrogen. These are linked with ________.


ionic bonds

nonpolar covalent bonds

polar covalent bonds

hydrogen bonds

Question: Together, just four elements make up more than 95 percent of the body's mass. These include ________.


calcium, magnesium, iron, and carbon

oxygen, calcium, iron, and nitrogen

sodium, chlorine, carbon, and hydrogen

oxygen, carbon, hydrogen, and nitrogen

Question: Which of the following statements about chemical bonds is true?


Covalent bonds are stronger than ionic bonds.

Hydrogen bonds occur between two atoms of hydrogen.

Bonding readily occurs between nonpolar and polar molecules.

A molecule of water is unlikely to bond with an ion.

Question: On the periodic table of the elements, mercury (Hg) has an atomic number of 80 and a mass number of 200.59. It has seven stable isotopes. The most abundant of these probably have ________.


about 80 neutrons each

fewer than 80 neutrons each

more than 80 neutrons each

more electrons than neutrons

Question: The characteristic that gives an element its distinctive properties is its number of ________.






Question: Nitrogen has an atomic number of seven. How many electron shells does it likely have?






Start FlashCards Download PDF Quiz Series Learn
Disclaimer:  This course does NOT provide the education or experience needed for the diagnosing or treating any medical condition,

all site contents are provided as general information only and should not be taken as medical advice.

Source:  Anatomy & Physiology MCQ. OpenStax College.
Copy and paste the following HTML code into your website or blog.
<iframe src="" width="600" height="600" frameborder="0" marginwidth="0" marginheight="0" scrolling="yes" style="border:1px solid #CCC; border-width:1px 1px 0; margin-bottom:5px" allowfullscreen webkitallowfullscreen mozallowfullscreen> </iframe>