Leerdoelen Metabolisme en Biochemie DT1
Hoofdstuk 1
Paragraaf 1
1. Know that 98% of the atoms in a living organism are carbon, oxygen, and hydrogen.
Out of the 90 natural elements, only three—oxygen, hydrogen, and carbon—make
up 98% of the atoms in an organism. These three elements are present in
significantly higher amounts in living organisms compared to the Earth's crust.
2. Understand that all known forms of life require water.
Oxygen and hydrogen are abundant in organisms due to the essential role of water.
Biochemist Albert Szent-Györgyi described water as “the matrix of life.”
Water, a simple molecule with just three atoms, is crucial for supporting life.
Scientists search for water on Mars because its presence implies the possibility of
life.
3. Describe the composition of fuel molecules and their products after oxidation.
Fuel molecules mainly consist of carbon, hydrogen, and oxygen. During combustion,
oxygen reacts with the fuel to produce carbon dioxide (CO₂) and water (H₂O),
releasing energy that powers cellular processes.
4. Explain the advantage of carbon over silicon as a major constituent of living cells.
Both carbon and silicon can form four covalent bonds, but carbon has several
advantages:
1. Carbon-carbon bonds are stronger than silicon-silicon bonds, resulting in
more stable structures.
2. The combustion of carbon releases more energy compared to silicon.
3. Carbon dioxide, a byproduct of carbon combustion, dissolves in water and
remains part of the biochemical cycle, while silicon dioxide (e.g., quartz) is
insoluble and excluded from such cycles.
5. Know that nitrogen, phosphorus, and sulfur also play important roles in organisms.
Nitrogen is a key component of amino acids and nucleotides.
Phosphorus is vital for energy transfer (e.g., ATP) and the structure of nucleic acids.
Sulfur is found in some amino acids (e.g., cysteine) and contributes to protein
structure through disulfide bonds.
Paragraaf 2
1. Describe and differentiate between the key classes of biomolecules.
, Proteins: versatile molecules made of amino acids that function as enzymes,
structural components, and signaling molecules.
Nucleic acids: linear molecules (DNA and RNA) that store and transmit genetic
information.
Lipids: function as fuel, signaling molecules, and membrane components, having
both hydrophilic and hydrophobic properties.
Carbohydrates: primary energy sources (e.g., glucose) and involved in cell
recognition.
2. Explain the various uses of proteins in the cell.
Signaling molecules, such as insulin, regulate processes like blood glucose levels.
Receptors detect signals and trigger cellular responses.
Structural components (e.g., cytoskeleton) provide stability to cells and tissues.
Defensive agents protect against environmental threats (e.g., antibodies).
Enzymes catalyze biochemical reactions without being permanently altered.
3. Describe the building blocks and structure of proteins.
Proteins are polymers of 20 amino acids linked by peptide bonds, forming linear
chains that fold into specific 3D structures.
4. Know the two main kinds of nucleic acids in the cell and that they are mainly used for storing
information.
DNA (deoxyribonucleic acid): stores hereditary information in the sequence of its
nucleotides.
RNA (ribonucleic acid): acts as a copy of DNA and is used as a template for protein
synthesis or transports genetic information (e.g., mRNA, tRNA).
5. Describe the building blocks and structure of nucleic acids.
A five-carbon sugar (deoxyribose or ribose).
A heterocyclic base.
At least one phosphate group.
6. Know the names and structures of the four “bases” used in DNA.
Adenine (A), Cytosine (C), Guanine (G), and Thymine (T).
In the DNA double helix, these bases pair specifically: A with T and C with G.
7. Understand the uses of lipids in the cell.
They form membranes that define cells and internal compartments.
They store energy, utilizing their hydrophobic components.
They act as signaling molecules.
8. Explain which classes of biomolecules are used as fuel.
The main fuel molecules are carbohydrates (e.g., glucose) and lipids.
The combustion of these molecules releases energy in the form of ATP.
9. Define what carbohydrates are and what the building blocks are for macromolecules such as
starch and glycogen.
Carbohydrates are molecules that serve as an energy source. The most common
example is glucose.
, In animals, glucose is stored as glycogen, and in plants, it is stored as starch. Both are
polymers of glucose units.
Hoofdstuk 2
Paragraaf 1
1. Define what is meant by Brownian motion.
, Brownian motion is the random movement of particles, such as pollen grains or dye
particles, caused by collisions with water or gas molecules that move randomly due
to thermal noise (random fluctuations in the energy content of the environment).
This motion was first observed by Robert Brown in 1827.
2. Relate the angstrom to other units of length such as the meter. (intro chapter 2)
An angstrom (Å) is a unit of length equal to 0.1 nanometers (nm) or 10⁻¹⁰ meters
(m). Noncovalent bonds typically act over distances of around 4 angstroms (0.4 nm).
3. Explain what is meant by transient chemical interactions. (intro chapter 2)
Transient chemical interactions are temporary and weak interactions between
molecules. These interactions allow for dynamic biological processes, such as
enzymes binding and releasing substrates or hormones temporarily binding to
receptors. They enable flexibility and adaptability within cells.
What are some examples of transient interactions being more favorable than
“strong covalent bonds”?
The interactions between phospholipids in a membrane
The interaction between an enzyme and its substrate
4. Know the length of a typical noncovalent bond. (intro chapter 2)
A typical noncovalent bond is approximately 4 angstroms (0.4 nm) in length. This is
the typical distance over which interactions like hydrogen bonds, van der Waals
interactions, and ionic interactions occur.
Paragraaf 2
1. Discuss how a water molecule can be considered to have a dipole, or to be polar.
A water molecule is polar due to the electronegativity of the oxygen atom, which
attracts electrons more strongly than the hydrogen atoms. This uneven distribution
of electron density creates a partial negative charge on the oxygen atom and partial
positive charges on the hydrogen atoms, resulting in a dipole.
2. Define the term hydrogen bond.
A hydrogen bond is a weak interaction that forms between a partially positive
hydrogen atom covalently bonded to an electronegative atom (such as oxygen or
nitrogen) and another electronegative atom with a partial negative charge. Hydrogen
bonds are crucial in stabilizing structures like DNA and proteins.
3. Describe the hydrophobic effect.
The hydrophobic effect refers to the tendency of nonpolar (hydrophobic) molecules
to avoid water. In an aqueous environment, water molecules form hydrogen-bonded
clusters that exclude hydrophobic molecules, causing them to aggregate. This effect
is critical for processes such as membrane formation and protein folding.
Paragraaf 3
1. List the three kinds of noncovalent bonds that mediate interactions among biomolecules and
describe their characteristics.
Hoofdstuk 1
Paragraaf 1
1. Know that 98% of the atoms in a living organism are carbon, oxygen, and hydrogen.
Out of the 90 natural elements, only three—oxygen, hydrogen, and carbon—make
up 98% of the atoms in an organism. These three elements are present in
significantly higher amounts in living organisms compared to the Earth's crust.
2. Understand that all known forms of life require water.
Oxygen and hydrogen are abundant in organisms due to the essential role of water.
Biochemist Albert Szent-Györgyi described water as “the matrix of life.”
Water, a simple molecule with just three atoms, is crucial for supporting life.
Scientists search for water on Mars because its presence implies the possibility of
life.
3. Describe the composition of fuel molecules and their products after oxidation.
Fuel molecules mainly consist of carbon, hydrogen, and oxygen. During combustion,
oxygen reacts with the fuel to produce carbon dioxide (CO₂) and water (H₂O),
releasing energy that powers cellular processes.
4. Explain the advantage of carbon over silicon as a major constituent of living cells.
Both carbon and silicon can form four covalent bonds, but carbon has several
advantages:
1. Carbon-carbon bonds are stronger than silicon-silicon bonds, resulting in
more stable structures.
2. The combustion of carbon releases more energy compared to silicon.
3. Carbon dioxide, a byproduct of carbon combustion, dissolves in water and
remains part of the biochemical cycle, while silicon dioxide (e.g., quartz) is
insoluble and excluded from such cycles.
5. Know that nitrogen, phosphorus, and sulfur also play important roles in organisms.
Nitrogen is a key component of amino acids and nucleotides.
Phosphorus is vital for energy transfer (e.g., ATP) and the structure of nucleic acids.
Sulfur is found in some amino acids (e.g., cysteine) and contributes to protein
structure through disulfide bonds.
Paragraaf 2
1. Describe and differentiate between the key classes of biomolecules.
, Proteins: versatile molecules made of amino acids that function as enzymes,
structural components, and signaling molecules.
Nucleic acids: linear molecules (DNA and RNA) that store and transmit genetic
information.
Lipids: function as fuel, signaling molecules, and membrane components, having
both hydrophilic and hydrophobic properties.
Carbohydrates: primary energy sources (e.g., glucose) and involved in cell
recognition.
2. Explain the various uses of proteins in the cell.
Signaling molecules, such as insulin, regulate processes like blood glucose levels.
Receptors detect signals and trigger cellular responses.
Structural components (e.g., cytoskeleton) provide stability to cells and tissues.
Defensive agents protect against environmental threats (e.g., antibodies).
Enzymes catalyze biochemical reactions without being permanently altered.
3. Describe the building blocks and structure of proteins.
Proteins are polymers of 20 amino acids linked by peptide bonds, forming linear
chains that fold into specific 3D structures.
4. Know the two main kinds of nucleic acids in the cell and that they are mainly used for storing
information.
DNA (deoxyribonucleic acid): stores hereditary information in the sequence of its
nucleotides.
RNA (ribonucleic acid): acts as a copy of DNA and is used as a template for protein
synthesis or transports genetic information (e.g., mRNA, tRNA).
5. Describe the building blocks and structure of nucleic acids.
A five-carbon sugar (deoxyribose or ribose).
A heterocyclic base.
At least one phosphate group.
6. Know the names and structures of the four “bases” used in DNA.
Adenine (A), Cytosine (C), Guanine (G), and Thymine (T).
In the DNA double helix, these bases pair specifically: A with T and C with G.
7. Understand the uses of lipids in the cell.
They form membranes that define cells and internal compartments.
They store energy, utilizing their hydrophobic components.
They act as signaling molecules.
8. Explain which classes of biomolecules are used as fuel.
The main fuel molecules are carbohydrates (e.g., glucose) and lipids.
The combustion of these molecules releases energy in the form of ATP.
9. Define what carbohydrates are and what the building blocks are for macromolecules such as
starch and glycogen.
Carbohydrates are molecules that serve as an energy source. The most common
example is glucose.
, In animals, glucose is stored as glycogen, and in plants, it is stored as starch. Both are
polymers of glucose units.
Hoofdstuk 2
Paragraaf 1
1. Define what is meant by Brownian motion.
, Brownian motion is the random movement of particles, such as pollen grains or dye
particles, caused by collisions with water or gas molecules that move randomly due
to thermal noise (random fluctuations in the energy content of the environment).
This motion was first observed by Robert Brown in 1827.
2. Relate the angstrom to other units of length such as the meter. (intro chapter 2)
An angstrom (Å) is a unit of length equal to 0.1 nanometers (nm) or 10⁻¹⁰ meters
(m). Noncovalent bonds typically act over distances of around 4 angstroms (0.4 nm).
3. Explain what is meant by transient chemical interactions. (intro chapter 2)
Transient chemical interactions are temporary and weak interactions between
molecules. These interactions allow for dynamic biological processes, such as
enzymes binding and releasing substrates or hormones temporarily binding to
receptors. They enable flexibility and adaptability within cells.
What are some examples of transient interactions being more favorable than
“strong covalent bonds”?
The interactions between phospholipids in a membrane
The interaction between an enzyme and its substrate
4. Know the length of a typical noncovalent bond. (intro chapter 2)
A typical noncovalent bond is approximately 4 angstroms (0.4 nm) in length. This is
the typical distance over which interactions like hydrogen bonds, van der Waals
interactions, and ionic interactions occur.
Paragraaf 2
1. Discuss how a water molecule can be considered to have a dipole, or to be polar.
A water molecule is polar due to the electronegativity of the oxygen atom, which
attracts electrons more strongly than the hydrogen atoms. This uneven distribution
of electron density creates a partial negative charge on the oxygen atom and partial
positive charges on the hydrogen atoms, resulting in a dipole.
2. Define the term hydrogen bond.
A hydrogen bond is a weak interaction that forms between a partially positive
hydrogen atom covalently bonded to an electronegative atom (such as oxygen or
nitrogen) and another electronegative atom with a partial negative charge. Hydrogen
bonds are crucial in stabilizing structures like DNA and proteins.
3. Describe the hydrophobic effect.
The hydrophobic effect refers to the tendency of nonpolar (hydrophobic) molecules
to avoid water. In an aqueous environment, water molecules form hydrogen-bonded
clusters that exclude hydrophobic molecules, causing them to aggregate. This effect
is critical for processes such as membrane formation and protein folding.
Paragraaf 3
1. List the three kinds of noncovalent bonds that mediate interactions among biomolecules and
describe their characteristics.
