Bio 235 Chapter 2 | Questions with 100% Verified Answers
| Latest Update 2026/2027
Question: Major elements
Answer: • Oxygen O
• Carbon C
• Hydrogen H
• Nitrogen N
(96% or body mass)
Question: Chemical element
Answer: The building blocks of all forms of matter (living and nonliving)
Question: Chemical symbol
Answer: one or two letters of the element's name in English, latin, or another language.
Question: Lesser Elements
Answer: Make up 3.6% of total body mass. Calcium, phosphorus, potassium, sulfur, sodium,
chlorine, magnesium and iron
Question: Trace elements
Answer: Account for about 0.4% of total body mass. There are 14 trace elements. Include
aluminium, boron, chromium, cobalt, copper, fluorine, iodine, manganese,
molybdenum,
selenium, silicon, tin, vanadium, and zinc.
Question: Atom
Answer: The smallest units of matter that retain the properties and characteristics of the
element.
Question: subatomic particles
Answer: Atoms are made up of dozens of subatomic particles. Most important are protons,
neutrons, and electrons.
Question: Proton
Answer: A subatomic particle that has a positive charge and that is found in the nucleus of an
atom
Question: Neutron
Answer: A subatomic particle that has no charge and that is found in the nucleus of an atom
, Question: Electron
Answer: A subatomic particle that has a negative charge that move about in the large space
surrounding the nucleus.
Question: electron shells
Answer: Depicted as simple circles around nucleus; each shell holds differing numbers of
electrons
Question: atomic number
Answer: the number of protons in the nucleus of an atom
Question: mass number
Answer: the sum of the protons and neutrons in an atom
Question: isotopes
Answer: atoms of an element that have the same number of protons but different number of
neutrons (and thus diff mass number)
Question: atomic mass/weight
Answer: average mass of all naturally occurring isotopes of that element
Question: Ion
Answer: an atom that has a positive or negative charge because it has unequal number of
protons
and electrons
Question: ionization
Answer: the process of giving up or gaining electrons
Question: molecule
Answer: when two or more atoms share electrons
Question: compound
Answer: a substance that contains atoms of two or more different elements
Question: free radical
Answer: an atom or group of atoms with an unpaired electron in the outermost shell
Question: Chemical bonds
Answer: the forces that hold together the atoms of a molecule or a compound
| Latest Update 2026/2027
Question: Major elements
Answer: • Oxygen O
• Carbon C
• Hydrogen H
• Nitrogen N
(96% or body mass)
Question: Chemical element
Answer: The building blocks of all forms of matter (living and nonliving)
Question: Chemical symbol
Answer: one or two letters of the element's name in English, latin, or another language.
Question: Lesser Elements
Answer: Make up 3.6% of total body mass. Calcium, phosphorus, potassium, sulfur, sodium,
chlorine, magnesium and iron
Question: Trace elements
Answer: Account for about 0.4% of total body mass. There are 14 trace elements. Include
aluminium, boron, chromium, cobalt, copper, fluorine, iodine, manganese,
molybdenum,
selenium, silicon, tin, vanadium, and zinc.
Question: Atom
Answer: The smallest units of matter that retain the properties and characteristics of the
element.
Question: subatomic particles
Answer: Atoms are made up of dozens of subatomic particles. Most important are protons,
neutrons, and electrons.
Question: Proton
Answer: A subatomic particle that has a positive charge and that is found in the nucleus of an
atom
Question: Neutron
Answer: A subatomic particle that has no charge and that is found in the nucleus of an atom
, Question: Electron
Answer: A subatomic particle that has a negative charge that move about in the large space
surrounding the nucleus.
Question: electron shells
Answer: Depicted as simple circles around nucleus; each shell holds differing numbers of
electrons
Question: atomic number
Answer: the number of protons in the nucleus of an atom
Question: mass number
Answer: the sum of the protons and neutrons in an atom
Question: isotopes
Answer: atoms of an element that have the same number of protons but different number of
neutrons (and thus diff mass number)
Question: atomic mass/weight
Answer: average mass of all naturally occurring isotopes of that element
Question: Ion
Answer: an atom that has a positive or negative charge because it has unequal number of
protons
and electrons
Question: ionization
Answer: the process of giving up or gaining electrons
Question: molecule
Answer: when two or more atoms share electrons
Question: compound
Answer: a substance that contains atoms of two or more different elements
Question: free radical
Answer: an atom or group of atoms with an unpaired electron in the outermost shell
Question: Chemical bonds
Answer: the forces that hold together the atoms of a molecule or a compound
