BIO 156 ACTUAL STUDY EXAM QUESTIONS AND
ANSWERS SET A+
✔✔What does CLPN stand for? - ✔✔-4 organic molecules of life
-C: Carbohydrates
-L: Lipids
-P: Proteins
-N: Nucleotides
✔✔Explain why water is called a "polar" molecule: - ✔✔-It has a positively charged end
(+) and a negatively charged end (-)
✔✔Why is pH 7 considered the "neutral" pH? - ✔✔- # of hydrogen ions and # of
hydroxide ions are equal H+ = OH -
-Does NOT have the caustic or dangerous characteristics of an acid or base.
✔✔What does a BUFFER do?
What do BUFFERS have to do with HOMEOSTASIS? - ✔✔-A buffer is a mixture of
molecules that RESIST CHANGE in pH
-Buffers maintain pH homeostasis
✔✔Explain how the COHESION and ADHESION properties of water help plants get
water from their roots to their leaves. - ✔✔The water molecules in soil and throughout
the body of a plant (roots, stems, leaves) are cohesive and stick together in long chains.
Water molecules are adhesive and stick to the sides of (xylem).
As water molecules evaporate off the surface of the leaves, they pull on that long chain
of water molecules and tug new water molecules into the roots.
As long as transpiration (evaporation off of the leaves) is happening, water will be pulled
into the roots and deep into the plant body.
, ✔✔Why does an ICE CUBE float in a glass of water? How is this important to some
organisms? - ✔✔-Because it is less dense than the liquid
-When water freezes in a lake it rises to the top creating an ice cap that prevents liquid
water below it from freezing and allows water organisms to survive throughout winter
✔✔-In lecture I suggested we use the acronym MCDAST to remember the UNIQUE
PROPERTIES of WATER.
-CHOOSE ONE of the letters in MCDAST and explain its meaning AND its special
significance for organisms or ecosystems - ✔✔-C (Cohesion)
-Water molecules in soil and throughout the body of a plant. It is sticky and can help
create long chains.
-Water molecules create larger and larger bodies of water where 60% of the species
live
✔✔HOW can you quickly determine if a carbohydrate is simple (MONOMER) or
complex (POLYMER)? - ✔✔-Monomer: # of carbons are ALWAYS equal to the # of
oxygen
#C = #O
-Polymer: # of carbon and # of oxygen aren't equal
✔✔Which of the following "word endings" is typical for carbohydrates? - ✔✔-ose
✔✔What exactly is a Protein? - ✔✔-One of the four major organic molecules of life
(CLPN)
-are large 3-D molecules
-30,000 different proteins that are structural & help build the body
-Example: Insulin, Keratin, Collagen
✔✔What exactly is a Lipid? - ✔✔-One of the four major organic molecules of life
-A source of energy for all organisms
-very important structural (body building molecule) for MANY organisms
-Example: Testosterone, Cholesterol (ex: fat in bacon)
✔✔What exactly is a Nucleotide? - ✔✔-One of the four major organic molecules of life
(CLPN)
ANSWERS SET A+
✔✔What does CLPN stand for? - ✔✔-4 organic molecules of life
-C: Carbohydrates
-L: Lipids
-P: Proteins
-N: Nucleotides
✔✔Explain why water is called a "polar" molecule: - ✔✔-It has a positively charged end
(+) and a negatively charged end (-)
✔✔Why is pH 7 considered the "neutral" pH? - ✔✔- # of hydrogen ions and # of
hydroxide ions are equal H+ = OH -
-Does NOT have the caustic or dangerous characteristics of an acid or base.
✔✔What does a BUFFER do?
What do BUFFERS have to do with HOMEOSTASIS? - ✔✔-A buffer is a mixture of
molecules that RESIST CHANGE in pH
-Buffers maintain pH homeostasis
✔✔Explain how the COHESION and ADHESION properties of water help plants get
water from their roots to their leaves. - ✔✔The water molecules in soil and throughout
the body of a plant (roots, stems, leaves) are cohesive and stick together in long chains.
Water molecules are adhesive and stick to the sides of (xylem).
As water molecules evaporate off the surface of the leaves, they pull on that long chain
of water molecules and tug new water molecules into the roots.
As long as transpiration (evaporation off of the leaves) is happening, water will be pulled
into the roots and deep into the plant body.
, ✔✔Why does an ICE CUBE float in a glass of water? How is this important to some
organisms? - ✔✔-Because it is less dense than the liquid
-When water freezes in a lake it rises to the top creating an ice cap that prevents liquid
water below it from freezing and allows water organisms to survive throughout winter
✔✔-In lecture I suggested we use the acronym MCDAST to remember the UNIQUE
PROPERTIES of WATER.
-CHOOSE ONE of the letters in MCDAST and explain its meaning AND its special
significance for organisms or ecosystems - ✔✔-C (Cohesion)
-Water molecules in soil and throughout the body of a plant. It is sticky and can help
create long chains.
-Water molecules create larger and larger bodies of water where 60% of the species
live
✔✔HOW can you quickly determine if a carbohydrate is simple (MONOMER) or
complex (POLYMER)? - ✔✔-Monomer: # of carbons are ALWAYS equal to the # of
oxygen
#C = #O
-Polymer: # of carbon and # of oxygen aren't equal
✔✔Which of the following "word endings" is typical for carbohydrates? - ✔✔-ose
✔✔What exactly is a Protein? - ✔✔-One of the four major organic molecules of life
(CLPN)
-are large 3-D molecules
-30,000 different proteins that are structural & help build the body
-Example: Insulin, Keratin, Collagen
✔✔What exactly is a Lipid? - ✔✔-One of the four major organic molecules of life
-A source of energy for all organisms
-very important structural (body building molecule) for MANY organisms
-Example: Testosterone, Cholesterol (ex: fat in bacon)
✔✔What exactly is a Nucleotide? - ✔✔-One of the four major organic molecules of life
(CLPN)
