AP BIO penguins unit 1 TBC Exam 2023 with complete
solution
What is a hydrogen bond?
A hydrogen bond is a weak bond interaction between the negative and positive regions
of two separate molecules.
Where are hydrogen bonds found in water?
Hydrogen bonds are found between the hydrogen atom of one water molecule and the
pair of electrons on an oxygen atom of a neighboring water molecule.
Where are hydrogen bonds found in DNA?
Hydrogen bonds exist between the two strands and form between a base
How many hydrogen bonds are found between each complementary base
pairing?
-Three hydrogen bonds form between guanine and cytosine.
-Two hydrogen bonds form between adenine and thymine or adenine and uracil.
What is the structure of an amino acid?
An amino acid's structure consists of a central carbon atom, bonded to an amino group
(NH2), a carboxyl group (COOH), and to a hydrogen atom.
What are the three options for the R group?
The 3 options for the R group is a hydrophobic group, a charged and polar group, and
an uncharged polar group.
How does the polarity of the R groups work?
-Hydrophobic/polar = repels water
-Hydrophilic/nonpolar = accepts water
What are three properties of water?
The 3 properties of water consist of cohesion/adhesion, specific heat, and surface
tension.
How does hydrogen bonding allow for specific heat?
-Water's high heat capacity is a property caused by hydrogen bonding among water
molecules.
-When heat is absorbed, hydrogen bonds are broken and water molecules can move
freely.
-When the temperature of water decreases, the hydrogen bonds are formed and
release a considerable amount of energy.
How does hydrogen bonding allow for cohesion/adhesion?
-Cohesion and adhesion in water are caused by the intermolecular attraction between
the partial negative oxygen of one water molecule, and the partial positive hydrogen of
another molecule.
How does hydrogen bonding allow for surface tension?
-Water molecules form hydrogen bonds with other water molecules which are strong
and flexible.
-This creates a high surface tension.
-This molecule at the surface tends to be pulled into the bulk of the liquid and minimizes
the surface area of a liquid.
Why is water is considered a polar molecule?
, -Since oxygen has a higher electronegativity than hydrogen, the electrons of the
molecule group closer to the oxygen than to the hydrogen atoms.
-Therefore, water is said to be a polar molecule, an uneven distribution of electron
density.
How can water move up a capillary tube to move from the roots to the leaves in a
plant?
-Capillary action can pull water up.
-To get water up to all its desired location, the forces of adhesion and cohesion go to
work.
How can a water strider can walk on water?
-Water striders use high surface tension of water and long and hydrophobic legs to help
them stay above water.
-Water striders use this surface tension to their advantage through their adapted legs
and weight being distributed.
What are the four macromolecules?
The 4 macromolecules are carbohydrates, proteins, lipids, and nucleic acids.
What are the elements found in a carbohydrate?
Carbohydrates are a class of chemical compounds composed of carbon, hydrogen, and
oxygen in 1:2:1 ratio.
What are three functions of carbohydrates in living organisms?
The 3 functions of carbohydrates in the body are to provide energy, store energy, build
macromolecules.
What are the elements found in a protein?
-Proteins are made of amino acids.
-Each AA is made of carbon, hydrogen, oxygen, and nitrogen.
-Most proteins also include sulfur.
What are the functional groups found in all amino acids?
A protein has an amine and a carboxylic acid group.
What are functions of proteins in living organisms?
Proteins help in metabolism by providing structural support and by acting as enzymes,
carriers, or hormones.
What are the elements found in nucleic acids?
Nucleic acids contain the same elements as proteins: carbon, hydrogen, oxygen,
nitrogen; plus phosphorus.
What are parts found in all nucleotides?
All nucleotides are composed of three parts: a five-carbon sugar, a phosphate, and a
nitrogen-rich structure called a nitrogenous base.
What are functions of nucleic acids in living organisms?
-The functions of nucleic acids have to do with the storage and expression of genetic
information.
-Deoxyribonucleic acid encodes the information the cell needs to make proteins.
What are the elements found in a lipid?
Lipids are composed of carbon, hydrogen and oxygen atoms, and in some cases
contain phosphorus, nitrogen, sulfur and other elements.
How are the three different types of lipids different?
solution
What is a hydrogen bond?
A hydrogen bond is a weak bond interaction between the negative and positive regions
of two separate molecules.
Where are hydrogen bonds found in water?
Hydrogen bonds are found between the hydrogen atom of one water molecule and the
pair of electrons on an oxygen atom of a neighboring water molecule.
Where are hydrogen bonds found in DNA?
Hydrogen bonds exist between the two strands and form between a base
How many hydrogen bonds are found between each complementary base
pairing?
-Three hydrogen bonds form between guanine and cytosine.
-Two hydrogen bonds form between adenine and thymine or adenine and uracil.
What is the structure of an amino acid?
An amino acid's structure consists of a central carbon atom, bonded to an amino group
(NH2), a carboxyl group (COOH), and to a hydrogen atom.
What are the three options for the R group?
The 3 options for the R group is a hydrophobic group, a charged and polar group, and
an uncharged polar group.
How does the polarity of the R groups work?
-Hydrophobic/polar = repels water
-Hydrophilic/nonpolar = accepts water
What are three properties of water?
The 3 properties of water consist of cohesion/adhesion, specific heat, and surface
tension.
How does hydrogen bonding allow for specific heat?
-Water's high heat capacity is a property caused by hydrogen bonding among water
molecules.
-When heat is absorbed, hydrogen bonds are broken and water molecules can move
freely.
-When the temperature of water decreases, the hydrogen bonds are formed and
release a considerable amount of energy.
How does hydrogen bonding allow for cohesion/adhesion?
-Cohesion and adhesion in water are caused by the intermolecular attraction between
the partial negative oxygen of one water molecule, and the partial positive hydrogen of
another molecule.
How does hydrogen bonding allow for surface tension?
-Water molecules form hydrogen bonds with other water molecules which are strong
and flexible.
-This creates a high surface tension.
-This molecule at the surface tends to be pulled into the bulk of the liquid and minimizes
the surface area of a liquid.
Why is water is considered a polar molecule?
, -Since oxygen has a higher electronegativity than hydrogen, the electrons of the
molecule group closer to the oxygen than to the hydrogen atoms.
-Therefore, water is said to be a polar molecule, an uneven distribution of electron
density.
How can water move up a capillary tube to move from the roots to the leaves in a
plant?
-Capillary action can pull water up.
-To get water up to all its desired location, the forces of adhesion and cohesion go to
work.
How can a water strider can walk on water?
-Water striders use high surface tension of water and long and hydrophobic legs to help
them stay above water.
-Water striders use this surface tension to their advantage through their adapted legs
and weight being distributed.
What are the four macromolecules?
The 4 macromolecules are carbohydrates, proteins, lipids, and nucleic acids.
What are the elements found in a carbohydrate?
Carbohydrates are a class of chemical compounds composed of carbon, hydrogen, and
oxygen in 1:2:1 ratio.
What are three functions of carbohydrates in living organisms?
The 3 functions of carbohydrates in the body are to provide energy, store energy, build
macromolecules.
What are the elements found in a protein?
-Proteins are made of amino acids.
-Each AA is made of carbon, hydrogen, oxygen, and nitrogen.
-Most proteins also include sulfur.
What are the functional groups found in all amino acids?
A protein has an amine and a carboxylic acid group.
What are functions of proteins in living organisms?
Proteins help in metabolism by providing structural support and by acting as enzymes,
carriers, or hormones.
What are the elements found in nucleic acids?
Nucleic acids contain the same elements as proteins: carbon, hydrogen, oxygen,
nitrogen; plus phosphorus.
What are parts found in all nucleotides?
All nucleotides are composed of three parts: a five-carbon sugar, a phosphate, and a
nitrogen-rich structure called a nitrogenous base.
What are functions of nucleic acids in living organisms?
-The functions of nucleic acids have to do with the storage and expression of genetic
information.
-Deoxyribonucleic acid encodes the information the cell needs to make proteins.
What are the elements found in a lipid?
Lipids are composed of carbon, hydrogen and oxygen atoms, and in some cases
contain phosphorus, nitrogen, sulfur and other elements.
How are the three different types of lipids different?
