Buyer: Victoria Proctor ()
Transaction ID: 4KS71350WY6468607
Biology Questions and Answers
The most important inorganic
Biochemistry substances for living beings are water,
mineral salts, carbon dioxide and
Introduction molecular oxygen. (There are several
other inorganic substances without
which cells would die.)
1. What are the chemical
elements that form most of
4. What are mineral salts?
living biological matter?
Where in living beings can
mineral salts be found?
The chemical elements that form most
of the molecules of living beings are
oxygen (O), carbon (C), hydrogen (H) Mineral salts are simple inorganic
and nitrogen (N). substances made of metallic chemical
elements, like iron, sodium, potassium,
calcium and magnesium, or of non-
metallic elements, like chlorine and
2. Living beings are made of phosphorus.
organic and inorganic
They can be found in non-solubilized
substances. According to the form, as part of structures of the
complexity of their molecules organism, like the calcium in bones.
how can each of those They can also be found solubilized in
substances be classified? water, as ions: for example, the sodium
and potassium cations within cells.
Inorganic substances, like water,
mineral salts, molecular oxygen and
carbon dioxide, are small molecules
made of few atoms. Organic substances, 5. What are the most
in general, like glucose, fatty acids and important organic molecules
proteins, are much more complex for living beings?
molecules made of sequences of
carbons bound in carbon chains. The There are many types of organic
capacity of carbon to form chains is one molecules that are important for the
of the main chemical facts that living beings. Especially important are
permitted the emergence of life on the amino acids and proteins, carbohydrates
planet. (including glucose), lipids and nucleic
acids (DNA and RNA).
Biochemistry Introduction Review -
3. What are the most Image Diversity: amino acid molecule
important inorganic molecular protein molecule carbohydrate molecule
substances for living beings? lipid molecule nucleic acid molecule
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,Buyer: Victoria Proctor ()
Transaction ID: 4KS71350WY6468607
Biology Questions and Answers
Glucose, for example, is the main
6. What are the main energy source for the formation of ATP
functions of the organic (adenosine triphosphate), a molecule
molecules for living beings? that is necessary in several metabolic
reactions. ATP is an organic molecule
Organic molecules, like proteins, lipids too and is itself the energy source for
and carbohydrates, perform several many biochemical reactions. Fat,
functions for living organisms. proteins and some types of organic
Noteworthy functions are the structural polymers, like starch and glycogen, that
function (as part of the material that are polymers of glucose, are energy
constitutes, delimits and maintains reservoirs for the organism.
organs, membranes, cell organelles,
etc.), the energetic function (chemical
reactions of the energetic metabolism),
the control and informative function 9. What are some examples of
(genetic code control, inter and the control and informative
intracellular signaling, endocrine function of organic molecules?
integration) and the enzymatic function
of proteins (facilitation of chemical
Based on genetic information, organic
reactions).
molecules control the entire work of the
cell. The nucleic acids, DNA and RNA,
are organic molecules that direct the
protein synthesis, and proteins in their
7. What are some examples of turn are the main molecules responsible
the structural function of for the diversity of cellular biological
organic molecules? tasks. In membranes and within the
cell, some organic molecules act as
Organic molecules have a structural information receptors and signalers.
function as they are part of cell Proteins and lipids have an important
membranes, cytoskeleton, organ walls role in the communication between cells
and blood vessel walls, bones, cartilages and tissues, acting as hormones,
and, in plants, of the conductive and substances that transmit information at
support tissues. a distance throughout the organism.
8. What are some examples of 10. What are biopolymers?
the energetic function of
organic molecules? Polymers are macromolecules made by
the union of several smaller identical
molecules, called monomers.
Since they are complex molecules,
Biopolymers are polymers present in the
presenting many chemical bonds,
living beings. Cellulose, starch and
organic molecules store large amount of
glycogen, for example, are polymers of
energy.
glucose.
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Questions and answers
12
,Buyer: Victoria Proctor ()
Transaction ID: 4KS71350WY6468607
Biology Questions and Answers
Water has key participationin
Water and Mineral organic reactions. What are
Salts examples of two types of
organic reactions in which
water is respectively
incorporated or liberated in
1. What is the approximate the products of these
percentage (in mass) of water reactions?
in the human body? Is this
percentage expected to be Photosynthesis is a biochemical process
larger in the adult or in the old in which water is incorporated into
organic molecules. In the reaction, the
individual?
hydrogen atoms from water go to the
produced glucose and the oxygen atoms
Approximately 65% of the human from water form the molecular oxygen
individual mass is water. The brain, for liberated: carbon dioxide + water +
example, has around 90% of water in light = glucose + molecular oxygen.
mass, the muscles, 85%, and the bones Aerobic respiration is an example of
have between 25% and 40% of water. biochemical reaction in which water is
produced: glucose + molecular oxygen
Younger adult individuals have = carbon dioxide + water.
proportionally more water in mass than
older individuals.
4. Is water a polar or a non-
polar molecule? What is the
2. What are the main
consequence of that
biological functions of water?
characteristic for the function
Water is the fundamental solvent for
of water as solvent?
chemical reactions of living beings; it is
the main means of substance Water is made of two atoms of
transportation in the cell and between hydrogen attached by covalent bond
cells and tissues and it is responsible for with one central atom of oxygen making
the maintenance of adequate an angular spatial structure. The
temperature for the functioning of the hydrogen atoms “lend” electrons to the
organism. Water is also the reagent or oxygen and consequently this atom
the product of many biochemical becomes more negative while the
reactions, like photosynthesis, cellular hydrogens become more positive. The
respiration, peptide bond for protein spatial geometry of the water molecule
formation, etc. makes it a polar molecule, with negative
and positive poles.
3.
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, Buyer: Victoria Proctor ()
Transaction ID: 4KS71350WY6468607
Biology Questions and Answers
Water is an excellent solvent for polar anions (OH-) by acids and bases in
substances because the electrical water solution.
activity (attraction and repulsion) of its
poles helps the separation and the
mixing of these substances, giving them
more movement and thus increasing the 7. Can the heat capacity of
number of molecular collisions and the water be considered small or
speed of chemical reactions. On the large? What is the biological
other hand, water is not good as a significance of that
solvent for non-polar substances. characteristic?
Polarity is one of the water properties.
From Thermology it is known that the
quantity of exchanged heat (Q) is equal
to the mass (m) multiplied by the
5. Which kind of polarity do specific heat of the substance (c)
multiplied by the variation of
water-soluble and fat-soluble temperature (T), Q = m.c.ΔT., and that
substances respectively have? heat capacity is Q/T, hence, m.c. Heat
capacity, however, relates to a specific
Water-soluble substances are polar body, since it considers mass, whereas
molecules, i.e., they have electrically specific heat relates to the general
charged areas. These molecules get the substance. Therefore it is more correct
description “water-soluble” because to refer to specific heat in this problem.
they are soluble in water, a polar
molecule too. Water has a specific heat of 1 cal/g.oC
which means that 1 oC per gram is
Fat-soluble substances are non-polar changed in its temperature with the
molecules, i.e., they are electrically addition or subtraction of 1 cal of
neutral. They get the description “fat- energy. This is a very elevated value
soluble” because they dissolve other (for example, the specific heat of
non-polar substances. ethanol is 0,58 cal/g.oC, and mercury, a
metal, has a specific heat of 0,033
cal/g. oC) making water an excellent
thermal protector against variations of
6. What is the importance of temperature. Even if sudden external
water for enzymatic activity? temperature changes occur, the internal
biological conditions are kept stable in
organisms which contain enough water.
Enzymes, biological catalysts, depend
on water to reach their substrates and
High specific heat is one of the most
bind to them. There is no enzymatic
important water properties.
activity without water. In addition,
enzymes depend on adequate pH
interval to work and the pH is a
consequence of the liberation of
hydrogen cations (H+) and hydroxyl
Questions and answers
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14
Transaction ID: 4KS71350WY6468607
Biology Questions and Answers
The most important inorganic
Biochemistry substances for living beings are water,
mineral salts, carbon dioxide and
Introduction molecular oxygen. (There are several
other inorganic substances without
which cells would die.)
1. What are the chemical
elements that form most of
4. What are mineral salts?
living biological matter?
Where in living beings can
mineral salts be found?
The chemical elements that form most
of the molecules of living beings are
oxygen (O), carbon (C), hydrogen (H) Mineral salts are simple inorganic
and nitrogen (N). substances made of metallic chemical
elements, like iron, sodium, potassium,
calcium and magnesium, or of non-
metallic elements, like chlorine and
2. Living beings are made of phosphorus.
organic and inorganic
They can be found in non-solubilized
substances. According to the form, as part of structures of the
complexity of their molecules organism, like the calcium in bones.
how can each of those They can also be found solubilized in
substances be classified? water, as ions: for example, the sodium
and potassium cations within cells.
Inorganic substances, like water,
mineral salts, molecular oxygen and
carbon dioxide, are small molecules
made of few atoms. Organic substances, 5. What are the most
in general, like glucose, fatty acids and important organic molecules
proteins, are much more complex for living beings?
molecules made of sequences of
carbons bound in carbon chains. The There are many types of organic
capacity of carbon to form chains is one molecules that are important for the
of the main chemical facts that living beings. Especially important are
permitted the emergence of life on the amino acids and proteins, carbohydrates
planet. (including glucose), lipids and nucleic
acids (DNA and RNA).
Biochemistry Introduction Review -
3. What are the most Image Diversity: amino acid molecule
important inorganic molecular protein molecule carbohydrate molecule
substances for living beings? lipid molecule nucleic acid molecule
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Questions and ansewrs
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,Buyer: Victoria Proctor ()
Transaction ID: 4KS71350WY6468607
Biology Questions and Answers
Glucose, for example, is the main
6. What are the main energy source for the formation of ATP
functions of the organic (adenosine triphosphate), a molecule
molecules for living beings? that is necessary in several metabolic
reactions. ATP is an organic molecule
Organic molecules, like proteins, lipids too and is itself the energy source for
and carbohydrates, perform several many biochemical reactions. Fat,
functions for living organisms. proteins and some types of organic
Noteworthy functions are the structural polymers, like starch and glycogen, that
function (as part of the material that are polymers of glucose, are energy
constitutes, delimits and maintains reservoirs for the organism.
organs, membranes, cell organelles,
etc.), the energetic function (chemical
reactions of the energetic metabolism),
the control and informative function 9. What are some examples of
(genetic code control, inter and the control and informative
intracellular signaling, endocrine function of organic molecules?
integration) and the enzymatic function
of proteins (facilitation of chemical
Based on genetic information, organic
reactions).
molecules control the entire work of the
cell. The nucleic acids, DNA and RNA,
are organic molecules that direct the
protein synthesis, and proteins in their
7. What are some examples of turn are the main molecules responsible
the structural function of for the diversity of cellular biological
organic molecules? tasks. In membranes and within the
cell, some organic molecules act as
Organic molecules have a structural information receptors and signalers.
function as they are part of cell Proteins and lipids have an important
membranes, cytoskeleton, organ walls role in the communication between cells
and blood vessel walls, bones, cartilages and tissues, acting as hormones,
and, in plants, of the conductive and substances that transmit information at
support tissues. a distance throughout the organism.
8. What are some examples of 10. What are biopolymers?
the energetic function of
organic molecules? Polymers are macromolecules made by
the union of several smaller identical
molecules, called monomers.
Since they are complex molecules,
Biopolymers are polymers present in the
presenting many chemical bonds,
living beings. Cellulose, starch and
organic molecules store large amount of
glycogen, for example, are polymers of
energy.
glucose.
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Questions and answers
12
,Buyer: Victoria Proctor ()
Transaction ID: 4KS71350WY6468607
Biology Questions and Answers
Water has key participationin
Water and Mineral organic reactions. What are
Salts examples of two types of
organic reactions in which
water is respectively
incorporated or liberated in
1. What is the approximate the products of these
percentage (in mass) of water reactions?
in the human body? Is this
percentage expected to be Photosynthesis is a biochemical process
larger in the adult or in the old in which water is incorporated into
organic molecules. In the reaction, the
individual?
hydrogen atoms from water go to the
produced glucose and the oxygen atoms
Approximately 65% of the human from water form the molecular oxygen
individual mass is water. The brain, for liberated: carbon dioxide + water +
example, has around 90% of water in light = glucose + molecular oxygen.
mass, the muscles, 85%, and the bones Aerobic respiration is an example of
have between 25% and 40% of water. biochemical reaction in which water is
produced: glucose + molecular oxygen
Younger adult individuals have = carbon dioxide + water.
proportionally more water in mass than
older individuals.
4. Is water a polar or a non-
polar molecule? What is the
2. What are the main
consequence of that
biological functions of water?
characteristic for the function
Water is the fundamental solvent for
of water as solvent?
chemical reactions of living beings; it is
the main means of substance Water is made of two atoms of
transportation in the cell and between hydrogen attached by covalent bond
cells and tissues and it is responsible for with one central atom of oxygen making
the maintenance of adequate an angular spatial structure. The
temperature for the functioning of the hydrogen atoms “lend” electrons to the
organism. Water is also the reagent or oxygen and consequently this atom
the product of many biochemical becomes more negative while the
reactions, like photosynthesis, cellular hydrogens become more positive. The
respiration, peptide bond for protein spatial geometry of the water molecule
formation, etc. makes it a polar molecule, with negative
and positive poles.
3.
Questions and answers
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, Buyer: Victoria Proctor ()
Transaction ID: 4KS71350WY6468607
Biology Questions and Answers
Water is an excellent solvent for polar anions (OH-) by acids and bases in
substances because the electrical water solution.
activity (attraction and repulsion) of its
poles helps the separation and the
mixing of these substances, giving them
more movement and thus increasing the 7. Can the heat capacity of
number of molecular collisions and the water be considered small or
speed of chemical reactions. On the large? What is the biological
other hand, water is not good as a significance of that
solvent for non-polar substances. characteristic?
Polarity is one of the water properties.
From Thermology it is known that the
quantity of exchanged heat (Q) is equal
to the mass (m) multiplied by the
5. Which kind of polarity do specific heat of the substance (c)
multiplied by the variation of
water-soluble and fat-soluble temperature (T), Q = m.c.ΔT., and that
substances respectively have? heat capacity is Q/T, hence, m.c. Heat
capacity, however, relates to a specific
Water-soluble substances are polar body, since it considers mass, whereas
molecules, i.e., they have electrically specific heat relates to the general
charged areas. These molecules get the substance. Therefore it is more correct
description “water-soluble” because to refer to specific heat in this problem.
they are soluble in water, a polar
molecule too. Water has a specific heat of 1 cal/g.oC
which means that 1 oC per gram is
Fat-soluble substances are non-polar changed in its temperature with the
molecules, i.e., they are electrically addition or subtraction of 1 cal of
neutral. They get the description “fat- energy. This is a very elevated value
soluble” because they dissolve other (for example, the specific heat of
non-polar substances. ethanol is 0,58 cal/g.oC, and mercury, a
metal, has a specific heat of 0,033
cal/g. oC) making water an excellent
thermal protector against variations of
6. What is the importance of temperature. Even if sudden external
water for enzymatic activity? temperature changes occur, the internal
biological conditions are kept stable in
organisms which contain enough water.
Enzymes, biological catalysts, depend
on water to reach their substrates and
High specific heat is one of the most
bind to them. There is no enzymatic
important water properties.
activity without water. In addition,
enzymes depend on adequate pH
interval to work and the pH is a
consequence of the liberation of
hydrogen cations (H+) and hydroxyl
Questions and answers
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14
