UMKC BIO 108 UNIT 1 EXAM QUESTIONS WITH VERIFIED SOLUTIONS LATEST UPDATE 2026
All organisms are composed of what? - Answers Matter
Matter is - Answers anything that takes up space and has mass
What is an element? - Answers substance that cannot be broken down to other substances by
chemical reactions
what is a compound? - Answers substance consisting of 2 or more elements
How many elements are essential to life? - Answers About 25 of the 92
What 4 elements make up 96% of living matter? - Answers carbon, hydrogen, oxygen, nitrogen
(CHON)
What 4 elements make up the remaining 4% of living matter? - Answers calcium, phosphorus,
potassium, sulfer (CaPKS)
What is an atom? - Answers smallest unit of matter that still retains the properties of an element
What are the 3 subatomic particles? - Answers protons+, neutrons, electrons-
What 2 subatomic particles are found in the nucleus? - Answers Protons+, neutrons
What is the mass of protons and neutrons? - Answers 1 Dalton (Da)
What is an atomic number? - Answers amount of protons in an atom
What is a mass number aka atomic mass? - Answers sum of protons and neutrons
What is an isotope? - Answers atoms with a different number of neutrons
What is a radioactive isotope? - Answers nucleus of an isotope spontaneously decays off particles and
energy
What are 3 things we use radioactive isotopes for in biological research? - Answers Dating fossils,
tracing atoms through metabolic processes, diagnosing medical disorders
How is energy defined? - Answers capacity to cause change by doing work
What is potential energy?** - Answers energy that matter possesses because of its location or
structure
How to electrons have potential energy? - Answers because of how they are arranged in relation to
the nucleus
What ratio of location to potential energy do electrons have?** - Answers more distant from the
nucleus the greater potential energy
Electrons can change shells by absorbing or losing energy in what amounts? - Answers exact amounts
i.e. they can't stop in between shells
What factor determines the chemical behavior of an atom? - Answers distribution of electrons in the
outermost shell
How many electrons can be stored in the first shell? - Answers 2
How many electrons can be stored in all other shells except the first? - Answers 8
What are electrons on the outermost shell called? - Answers valence electrons
What is an atom with a complete valence shell? - Answers unreactive
What is an orbital? - Answers 3D space where an electron can be found 90% of the time
How many electrons can occupy an orbital? - Answers no more than 2
What forms when atoms with an incomplete valence shell share or transfer valence electrons with
other atoms? - Answers bonds
What is a covalent bond? - Answers sharing of valence electrons by 2 atoms
Do ions form from covalent or ionic bonds? - Answers ionic bonds
What is a molecule? - Answers 2 or more atoms held together by covalent bonds
What is electronegativity?** - Answers atoms attraction for electrons
What is a nonpolar covalent bond? - Answers atoms share electrons equally
What is a polar covalent bond? - Answers one atom is more electronegative so the electrons are not
shared equally
What is an ionic bond? - Answers attraction between anions and cations
What is an anion? - Answers negatively charged ion
What is a cation? - Answers positively charged ion
Why are weak chemical bonds important? - Answers reinforce molecules shapes and adheres
molecules together
What is a hydrogen covalent bond? - Answers hydrogen atom covalently bonded to one
electronegative atom is also attracted to another electronegative atom
In living cells what are the most common electronegative partners? - Answers oxygen and nitrogen
, What are van der waals interactions? - Answers weak attractions formed by molecules or atoms that
are very close together
Why is the shape of a molecule so important? - Answers molecules recognize and interact with each
other based on shape
What is the biological medium of earth? - Answers water
Cells are made up of what percent of water? - Answers 70-95%
What allows water molecules to have 'special' abilities? - Answers polarity allows water molecules to
form hydrogen bonds with other water molecules
What are the 4 properties of water that facilitate life? - Answers Cohesive behavior, ability to
moderate temperature, expansion upon freezing, versatility as a solvent
What is cohesion? - Answers hydrogen bonds hold molecules together allowing the transport of water
against gravity in plants
What is adhesion? - Answers attractions of water to other polar molecules allowing water to travel
and climb cell walls
What is surface tension? - Answers how hard it is the break the surface of a liquid because of
cohesion
What is moderation of temperature? - Answers water can absorb or release large amounts of heat
with only slight change in its own temperature
What is kinetic energy? - Answers energy of motion
What is heat? - Answers total amount of kinetic energy depending on the matter's volume
What is temperature? - Answers intensity of heat due to the average kinetic energy of molecules
regardless of water
What is a calorie? - Answers amount of heat it takes to raise the temperature of 1g of water by 1º C
How is heat released and absorbed by water? - Answers released when hydrogen bonds form and
absorbed when hydrogen bonds break
Is waters's specific heat high or low? - Answers high (1cal/gºC)
What is heat of vaporization? - Answers heat a liquid must absorb for 1g to be converted to gas
Does water have a high or low heat of vaporization? - Answers high (580cal 1g at 25ºC)
What is evaporative cooling? - Answers as water evaporates it leaves behind cooler molecules
What does water's high heat capacity do for life? - Answers minimizes temperature fluctuations
within limits that permit life
What does water's evaporative cooling do for life? - Answers stabilizes temperatures in organisms and
bodies of water
What is expansion upon freezing? - Answers water is less dense solid than liquid so it expands and
floats
Why is water's expansion upon freezing important? - Answers allows water to freeze from the top
down insulating the water and organisms below it
What is a solution? - Answers liquid that is a homogeneous mixture of 2 or more substances
What is a solvent? - Answers dissolving agent of a solution
What is a solute? - Answers substance that is dissolved
What is an aqueous solution? - Answers water is the solvent
Why is water a versatile solvent? - Answers its polarity
What is a hydration shell? - Answers sphere of water molecules that surrounds an ion in ionic
compounds weakening the attraction of the compound's molecules
How does water dissolve nonionic compounds? - Answers hydrogen bonds form from the water
ripping the compounds apart
What does hydrophilic mean? - Answers attracted to water
What does hydrophobic mean? - Answers fears water
What forms from large hydrophilic molecules that can't dissolve in water? - Answers forms colloids-
stable suspension of fine particles
What is molecular mass? - Answers sum of all masses of all atoms in a molecule
What is avogadro's number? - Answers 6.02e23; number of molecules in a mole
What is molar mass? - Answers mass of 1 mole of a substance
Is the molecular mass and molar mass the same? - Answers yes just switch Da to g
What is molarity? - Answers number of moles of solute per liter of solution?
How are hydronium ions (H3O+) and hydroxide ions (OH-) formed? - Answers hydrogen atom in a
hydrogen bond between 2 water molecules shift from 1 molecule to the other
All organisms are composed of what? - Answers Matter
Matter is - Answers anything that takes up space and has mass
What is an element? - Answers substance that cannot be broken down to other substances by
chemical reactions
what is a compound? - Answers substance consisting of 2 or more elements
How many elements are essential to life? - Answers About 25 of the 92
What 4 elements make up 96% of living matter? - Answers carbon, hydrogen, oxygen, nitrogen
(CHON)
What 4 elements make up the remaining 4% of living matter? - Answers calcium, phosphorus,
potassium, sulfer (CaPKS)
What is an atom? - Answers smallest unit of matter that still retains the properties of an element
What are the 3 subatomic particles? - Answers protons+, neutrons, electrons-
What 2 subatomic particles are found in the nucleus? - Answers Protons+, neutrons
What is the mass of protons and neutrons? - Answers 1 Dalton (Da)
What is an atomic number? - Answers amount of protons in an atom
What is a mass number aka atomic mass? - Answers sum of protons and neutrons
What is an isotope? - Answers atoms with a different number of neutrons
What is a radioactive isotope? - Answers nucleus of an isotope spontaneously decays off particles and
energy
What are 3 things we use radioactive isotopes for in biological research? - Answers Dating fossils,
tracing atoms through metabolic processes, diagnosing medical disorders
How is energy defined? - Answers capacity to cause change by doing work
What is potential energy?** - Answers energy that matter possesses because of its location or
structure
How to electrons have potential energy? - Answers because of how they are arranged in relation to
the nucleus
What ratio of location to potential energy do electrons have?** - Answers more distant from the
nucleus the greater potential energy
Electrons can change shells by absorbing or losing energy in what amounts? - Answers exact amounts
i.e. they can't stop in between shells
What factor determines the chemical behavior of an atom? - Answers distribution of electrons in the
outermost shell
How many electrons can be stored in the first shell? - Answers 2
How many electrons can be stored in all other shells except the first? - Answers 8
What are electrons on the outermost shell called? - Answers valence electrons
What is an atom with a complete valence shell? - Answers unreactive
What is an orbital? - Answers 3D space where an electron can be found 90% of the time
How many electrons can occupy an orbital? - Answers no more than 2
What forms when atoms with an incomplete valence shell share or transfer valence electrons with
other atoms? - Answers bonds
What is a covalent bond? - Answers sharing of valence electrons by 2 atoms
Do ions form from covalent or ionic bonds? - Answers ionic bonds
What is a molecule? - Answers 2 or more atoms held together by covalent bonds
What is electronegativity?** - Answers atoms attraction for electrons
What is a nonpolar covalent bond? - Answers atoms share electrons equally
What is a polar covalent bond? - Answers one atom is more electronegative so the electrons are not
shared equally
What is an ionic bond? - Answers attraction between anions and cations
What is an anion? - Answers negatively charged ion
What is a cation? - Answers positively charged ion
Why are weak chemical bonds important? - Answers reinforce molecules shapes and adheres
molecules together
What is a hydrogen covalent bond? - Answers hydrogen atom covalently bonded to one
electronegative atom is also attracted to another electronegative atom
In living cells what are the most common electronegative partners? - Answers oxygen and nitrogen
, What are van der waals interactions? - Answers weak attractions formed by molecules or atoms that
are very close together
Why is the shape of a molecule so important? - Answers molecules recognize and interact with each
other based on shape
What is the biological medium of earth? - Answers water
Cells are made up of what percent of water? - Answers 70-95%
What allows water molecules to have 'special' abilities? - Answers polarity allows water molecules to
form hydrogen bonds with other water molecules
What are the 4 properties of water that facilitate life? - Answers Cohesive behavior, ability to
moderate temperature, expansion upon freezing, versatility as a solvent
What is cohesion? - Answers hydrogen bonds hold molecules together allowing the transport of water
against gravity in plants
What is adhesion? - Answers attractions of water to other polar molecules allowing water to travel
and climb cell walls
What is surface tension? - Answers how hard it is the break the surface of a liquid because of
cohesion
What is moderation of temperature? - Answers water can absorb or release large amounts of heat
with only slight change in its own temperature
What is kinetic energy? - Answers energy of motion
What is heat? - Answers total amount of kinetic energy depending on the matter's volume
What is temperature? - Answers intensity of heat due to the average kinetic energy of molecules
regardless of water
What is a calorie? - Answers amount of heat it takes to raise the temperature of 1g of water by 1º C
How is heat released and absorbed by water? - Answers released when hydrogen bonds form and
absorbed when hydrogen bonds break
Is waters's specific heat high or low? - Answers high (1cal/gºC)
What is heat of vaporization? - Answers heat a liquid must absorb for 1g to be converted to gas
Does water have a high or low heat of vaporization? - Answers high (580cal 1g at 25ºC)
What is evaporative cooling? - Answers as water evaporates it leaves behind cooler molecules
What does water's high heat capacity do for life? - Answers minimizes temperature fluctuations
within limits that permit life
What does water's evaporative cooling do for life? - Answers stabilizes temperatures in organisms and
bodies of water
What is expansion upon freezing? - Answers water is less dense solid than liquid so it expands and
floats
Why is water's expansion upon freezing important? - Answers allows water to freeze from the top
down insulating the water and organisms below it
What is a solution? - Answers liquid that is a homogeneous mixture of 2 or more substances
What is a solvent? - Answers dissolving agent of a solution
What is a solute? - Answers substance that is dissolved
What is an aqueous solution? - Answers water is the solvent
Why is water a versatile solvent? - Answers its polarity
What is a hydration shell? - Answers sphere of water molecules that surrounds an ion in ionic
compounds weakening the attraction of the compound's molecules
How does water dissolve nonionic compounds? - Answers hydrogen bonds form from the water
ripping the compounds apart
What does hydrophilic mean? - Answers attracted to water
What does hydrophobic mean? - Answers fears water
What forms from large hydrophilic molecules that can't dissolve in water? - Answers forms colloids-
stable suspension of fine particles
What is molecular mass? - Answers sum of all masses of all atoms in a molecule
What is avogadro's number? - Answers 6.02e23; number of molecules in a mole
What is molar mass? - Answers mass of 1 mole of a substance
Is the molecular mass and molar mass the same? - Answers yes just switch Da to g
What is molarity? - Answers number of moles of solute per liter of solution?
How are hydronium ions (H3O+) and hydroxide ions (OH-) formed? - Answers hydrogen atom in a
hydrogen bond between 2 water molecules shift from 1 molecule to the other
