BIOD 101 MODULES 1-6 & FINAL
EXAM 2026-2027 | Portage
Learning | Complete Verified Q&As |
Review Guide | Pass Guaranteed -
A+ Graded
[MODULE 1: BIOMACROMOLECULES, CELL STRUCTURE & MEMBRANE TRANSPORT - 80
Questions]
Section 1.1: Biomacromolecules (Questions 1-30)
1. Which four elements make up approximately 96% of living matter?
A) Carbon, hydrogen, calcium, oxygen
B) Carbon, hydrogen, oxygen, nitrogen [CORRECT]
C) Carbon, oxygen, phosphorus, sulfur
D) Nitrogen, oxygen, calcium, hydrogen
Rationale: Carbon, hydrogen, oxygen, and nitrogen are the four most abundant elements in
biological systems. Carbon forms the backbone of organic molecules, hydrogen and oxygen are
essential for water and macromolecules, and nitrogen is critical for amino acids and nucleic
acids. (See 1.1)
2. What is the primary source of fuel for most organisms?
A) Lipids
B) Proteins
C) Carbohydrates [CORRECT]
D) Nucleic acids
Rationale: Carbohydrates serve as the primary energy source for cellular respiration. Glucose, a
simple sugar, is the preferred substrate for ATP production through glycolysis and cellular
respiration. While lipids store more energy per gram, carbohydrates are the immediate fuel
source. (See 1.1)
3. Which of the following is NOT one of the four major categories of biological macromolecules?
A) Carbohydrates
B) Lipids
C) Steroids [CORRECT]
D) Nucleic acids
, ationale: Steroids are a subclass of lipids, not a major category. The four major biological
R
macromolecules are carbohydrates, lipids, proteins, and nucleic acids. Steroids like cholesterol
are lipid-derived molecules with distinct ring structures. (See 1.1)
4. What is the chemical formula commonly associated with carbohydrates?
A) C₂H₄O₂
B) (CH₂O)n [CORRECT]
C) C₆H₁₂O₆ only
D) CH₃(CH₂)ₙCOOH
Rationale: Carbohydrates typically follow the general formula (CH₂O)n, where n is usually 3 or
more. This reflects their composition of carbon, hydrogen, and oxygen in a 1:2:1 ratio. Glucose
(C₆H₁₂O₆) is a specific example, not the general formula. (See 1.1)
5. Which type of covalent bond connects amino acids in a protein chain?
A) Glycosidic bond
B) Ester bond
C) Peptide bond [CORRECT]
D) Hydrogen bond
Rationale: Peptide bonds form between the carboxyl group of one amino acid and the amino
group of another, releasing water (dehydration synthesis). This covalent bond is the backbone
of protein structure. Glycosidic bonds link sugars, ester bonds link fatty acids to glycerol, and
hydrogen bonds stabilize secondary/tertiary protein structure. (See 1.1)
6. What makes lipids unique compared to other biological macromolecules?
A) They contain nitrogen
B) They are insoluble in water [CORRECT]
C) They are polymers of monosaccharides
D) They form peptide bonds
Rationale: Lipids are hydrophobic (nonpolar) due to their hydrocarbon chains, making them
insoluble in water. Unlike carbohydrates, proteins, and nucleic acids, lipids are not true polymers
and do not dissolve in aqueous environments. This property allows them to form membranes
and store energy efficiently. (See 1.1)
7. Which component of phospholipids faces the aqueous environment in a cell membrane?
A) Fatty acid tails
B) Glycerol backbone
C) Polar phosphate head [CORRECT]
D) Steroid nucleus
Rationale: Phospholipids are amphipathic molecules with hydrophilic (water-loving) phosphate
heads facing outward toward water and hydrophobic (water-fearing) fatty acid tails facing
inward, away from water. This arrangement forms the lipid bilayer structure of cell membranes.
(See 1.1)
8. Which of the following is NOT a function of proteins?
A) Enzymatic catalysis
B) Energy storage (primary function) [CORRECT]
C) Transport across membranes
D) Immune defense (antibodies)
, ationale: While proteins can be metabolized for energy, their primary functions include
R
enzymatic catalysis, transport (ion channels, carriers), structural support, immune defense
(antibodies), and cell signaling. Lipids and carbohydrates serve as primary energy storage
molecules. (See 1.1)
9. What is the relationship between protein structure and function?
A) Structure and function are unrelated
B) Function determines structure
C) Structure directly determines function [CORRECT]
D) Only primary structure matters for function
Rationale: The three-dimensional conformation of a protein (secondary, tertiary, quaternary
structure) determines its specific function. Denaturation (loss of structure) leads to loss of
function. For example, the specific shape of enzyme active sites determines substrate
specificity. (See 1.1)
10. Which nucleic acid serves as the repository of genetic information in cells?
A) mRNA
B) rRNA
C) DNA [CORRECT]
D) tRNA
Rationale: DNA (deoxyribonucleic acid) stores the genetic blueprint for an organism. RNA
molecules (mRNA, rRNA, tRNA) are involved in protein synthesis but do not serve as the
permanent genetic repository. DNA's double-helix structure provides stability for long-term
information storage. (See 1.1)
11. What is the role of RNA in protein synthesis?
A) Long-term genetic storage
B) Deciphers DNA to synthesize proteins [CORRECT]
C) Forms the structural backbone of chromosomes
D) Stores energy for translation
Rationale: RNA acts as an intermediary between DNA and protein synthesis. mRNA carries
genetic code from DNA to ribosomes, rRNA forms ribosomal structure, and tRNA brings amino
acids to the ribosome. DNA remains in the nucleus while RNA carries information to the
cytoplasm. (See 1.1)
12. Which elements are considered essential elements required for human life?
A) Only carbon, hydrogen, oxygen, nitrogen
B) Elements required for normal biological function [CORRECT]
C) Only elements found in proteins
D) Trace elements only
Rationale: Essential elements are those required for normal biological function and must be
obtained from the diet. This includes bulk elements (C, H, O, N, P, S) and trace elements (Fe,
Cu, Zn, I, etc.) in smaller quantities. Both categories are essential for life processes. (See 1.1)
13. What distinguishes essential amino acids from non-essential amino acids?
A) Essential amino acids are more abundant in cells
B) Essential amino acids must be obtained from diet [CORRECT]
C) Non-essential amino acids are not used in proteins
D) Essential amino acids are only found in animals
, ationale: Humans can synthesize non-essential amino acids but must obtain essential amino
R
acids (9 total: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine,
tryptophan, valine) from dietary protein. This distinction is crucial for nutritional planning. (See
1.1)
14. Which of the following is the most abundant type of lipid in biological systems?
A) Phospholipids
B) Steroids
C) Triglycerides [CORRECT]
D) Waxes
Rationale: Triglycerides (triacylglycerols) are the most abundant lipids, serving as the primary
form of energy storage in adipose tissue. They consist of glycerol bonded to three fatty acids.
Phospholipids are crucial for membranes but less abundant by mass. (See 1.1)
15. What type of bond forms between the phosphate group and glycerol in phospholipids?
A) Peptide bond
B) Glycosidic bond
C) Ester bond [CORRECT]
D) Hydrogen bond
Rationale: Ester bonds link the phosphate group to glycerol and the fatty acids to glycerol in
phospholipids. This differs from peptide bonds (proteins), glycosidic bonds (carbohydrates), and
hydrogen bonds (weak intermolecular forces). (See 1.1)
16. Which trace element is essential for thyroid hormone synthesis?
A) Iron
B) Zinc
C) Iodine [CORRECT]
D) Calcium
Rationale: Iodine is a trace element required only in small quantities but is essential for thyroid
hormone (T3 and T4) synthesis. Iron is essential for hemoglobin, zinc for enzyme function, and
calcium (a bulk element) for bone structure and signaling. (See 1.1)
17. What is the monomer unit of proteins?
A) Monosaccharides
B) Fatty acids
C) Amino acids [CORRECT]
D) Nucleotides
Rationale: Amino acids are the building blocks (monomers) of proteins. Twenty different amino
acids combine through peptide bonds to form polypeptide chains. Monosaccharides build
carbohydrates, fatty acids combine with glycerol for lipids, and nucleotides form nucleic acids.
(See 1.1)
18. Which level of protein structure involves interactions between R-groups (side chains)?
A) Primary structure
B) Secondary structure
C) Tertiary structure [CORRECT]
D) Quaternary structure only
Rationale: Tertiary structure involves interactions between R-groups, including hydrophobic
interactions, hydrogen bonds, ionic bonds, and disulfide bridges. Primary structure is the amino
EXAM 2026-2027 | Portage
Learning | Complete Verified Q&As |
Review Guide | Pass Guaranteed -
A+ Graded
[MODULE 1: BIOMACROMOLECULES, CELL STRUCTURE & MEMBRANE TRANSPORT - 80
Questions]
Section 1.1: Biomacromolecules (Questions 1-30)
1. Which four elements make up approximately 96% of living matter?
A) Carbon, hydrogen, calcium, oxygen
B) Carbon, hydrogen, oxygen, nitrogen [CORRECT]
C) Carbon, oxygen, phosphorus, sulfur
D) Nitrogen, oxygen, calcium, hydrogen
Rationale: Carbon, hydrogen, oxygen, and nitrogen are the four most abundant elements in
biological systems. Carbon forms the backbone of organic molecules, hydrogen and oxygen are
essential for water and macromolecules, and nitrogen is critical for amino acids and nucleic
acids. (See 1.1)
2. What is the primary source of fuel for most organisms?
A) Lipids
B) Proteins
C) Carbohydrates [CORRECT]
D) Nucleic acids
Rationale: Carbohydrates serve as the primary energy source for cellular respiration. Glucose, a
simple sugar, is the preferred substrate for ATP production through glycolysis and cellular
respiration. While lipids store more energy per gram, carbohydrates are the immediate fuel
source. (See 1.1)
3. Which of the following is NOT one of the four major categories of biological macromolecules?
A) Carbohydrates
B) Lipids
C) Steroids [CORRECT]
D) Nucleic acids
, ationale: Steroids are a subclass of lipids, not a major category. The four major biological
R
macromolecules are carbohydrates, lipids, proteins, and nucleic acids. Steroids like cholesterol
are lipid-derived molecules with distinct ring structures. (See 1.1)
4. What is the chemical formula commonly associated with carbohydrates?
A) C₂H₄O₂
B) (CH₂O)n [CORRECT]
C) C₆H₁₂O₆ only
D) CH₃(CH₂)ₙCOOH
Rationale: Carbohydrates typically follow the general formula (CH₂O)n, where n is usually 3 or
more. This reflects their composition of carbon, hydrogen, and oxygen in a 1:2:1 ratio. Glucose
(C₆H₁₂O₆) is a specific example, not the general formula. (See 1.1)
5. Which type of covalent bond connects amino acids in a protein chain?
A) Glycosidic bond
B) Ester bond
C) Peptide bond [CORRECT]
D) Hydrogen bond
Rationale: Peptide bonds form between the carboxyl group of one amino acid and the amino
group of another, releasing water (dehydration synthesis). This covalent bond is the backbone
of protein structure. Glycosidic bonds link sugars, ester bonds link fatty acids to glycerol, and
hydrogen bonds stabilize secondary/tertiary protein structure. (See 1.1)
6. What makes lipids unique compared to other biological macromolecules?
A) They contain nitrogen
B) They are insoluble in water [CORRECT]
C) They are polymers of monosaccharides
D) They form peptide bonds
Rationale: Lipids are hydrophobic (nonpolar) due to their hydrocarbon chains, making them
insoluble in water. Unlike carbohydrates, proteins, and nucleic acids, lipids are not true polymers
and do not dissolve in aqueous environments. This property allows them to form membranes
and store energy efficiently. (See 1.1)
7. Which component of phospholipids faces the aqueous environment in a cell membrane?
A) Fatty acid tails
B) Glycerol backbone
C) Polar phosphate head [CORRECT]
D) Steroid nucleus
Rationale: Phospholipids are amphipathic molecules with hydrophilic (water-loving) phosphate
heads facing outward toward water and hydrophobic (water-fearing) fatty acid tails facing
inward, away from water. This arrangement forms the lipid bilayer structure of cell membranes.
(See 1.1)
8. Which of the following is NOT a function of proteins?
A) Enzymatic catalysis
B) Energy storage (primary function) [CORRECT]
C) Transport across membranes
D) Immune defense (antibodies)
, ationale: While proteins can be metabolized for energy, their primary functions include
R
enzymatic catalysis, transport (ion channels, carriers), structural support, immune defense
(antibodies), and cell signaling. Lipids and carbohydrates serve as primary energy storage
molecules. (See 1.1)
9. What is the relationship between protein structure and function?
A) Structure and function are unrelated
B) Function determines structure
C) Structure directly determines function [CORRECT]
D) Only primary structure matters for function
Rationale: The three-dimensional conformation of a protein (secondary, tertiary, quaternary
structure) determines its specific function. Denaturation (loss of structure) leads to loss of
function. For example, the specific shape of enzyme active sites determines substrate
specificity. (See 1.1)
10. Which nucleic acid serves as the repository of genetic information in cells?
A) mRNA
B) rRNA
C) DNA [CORRECT]
D) tRNA
Rationale: DNA (deoxyribonucleic acid) stores the genetic blueprint for an organism. RNA
molecules (mRNA, rRNA, tRNA) are involved in protein synthesis but do not serve as the
permanent genetic repository. DNA's double-helix structure provides stability for long-term
information storage. (See 1.1)
11. What is the role of RNA in protein synthesis?
A) Long-term genetic storage
B) Deciphers DNA to synthesize proteins [CORRECT]
C) Forms the structural backbone of chromosomes
D) Stores energy for translation
Rationale: RNA acts as an intermediary between DNA and protein synthesis. mRNA carries
genetic code from DNA to ribosomes, rRNA forms ribosomal structure, and tRNA brings amino
acids to the ribosome. DNA remains in the nucleus while RNA carries information to the
cytoplasm. (See 1.1)
12. Which elements are considered essential elements required for human life?
A) Only carbon, hydrogen, oxygen, nitrogen
B) Elements required for normal biological function [CORRECT]
C) Only elements found in proteins
D) Trace elements only
Rationale: Essential elements are those required for normal biological function and must be
obtained from the diet. This includes bulk elements (C, H, O, N, P, S) and trace elements (Fe,
Cu, Zn, I, etc.) in smaller quantities. Both categories are essential for life processes. (See 1.1)
13. What distinguishes essential amino acids from non-essential amino acids?
A) Essential amino acids are more abundant in cells
B) Essential amino acids must be obtained from diet [CORRECT]
C) Non-essential amino acids are not used in proteins
D) Essential amino acids are only found in animals
, ationale: Humans can synthesize non-essential amino acids but must obtain essential amino
R
acids (9 total: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine,
tryptophan, valine) from dietary protein. This distinction is crucial for nutritional planning. (See
1.1)
14. Which of the following is the most abundant type of lipid in biological systems?
A) Phospholipids
B) Steroids
C) Triglycerides [CORRECT]
D) Waxes
Rationale: Triglycerides (triacylglycerols) are the most abundant lipids, serving as the primary
form of energy storage in adipose tissue. They consist of glycerol bonded to three fatty acids.
Phospholipids are crucial for membranes but less abundant by mass. (See 1.1)
15. What type of bond forms between the phosphate group and glycerol in phospholipids?
A) Peptide bond
B) Glycosidic bond
C) Ester bond [CORRECT]
D) Hydrogen bond
Rationale: Ester bonds link the phosphate group to glycerol and the fatty acids to glycerol in
phospholipids. This differs from peptide bonds (proteins), glycosidic bonds (carbohydrates), and
hydrogen bonds (weak intermolecular forces). (See 1.1)
16. Which trace element is essential for thyroid hormone synthesis?
A) Iron
B) Zinc
C) Iodine [CORRECT]
D) Calcium
Rationale: Iodine is a trace element required only in small quantities but is essential for thyroid
hormone (T3 and T4) synthesis. Iron is essential for hemoglobin, zinc for enzyme function, and
calcium (a bulk element) for bone structure and signaling. (See 1.1)
17. What is the monomer unit of proteins?
A) Monosaccharides
B) Fatty acids
C) Amino acids [CORRECT]
D) Nucleotides
Rationale: Amino acids are the building blocks (monomers) of proteins. Twenty different amino
acids combine through peptide bonds to form polypeptide chains. Monosaccharides build
carbohydrates, fatty acids combine with glycerol for lipids, and nucleotides form nucleic acids.
(See 1.1)
18. Which level of protein structure involves interactions between R-groups (side chains)?
A) Primary structure
B) Secondary structure
C) Tertiary structure [CORRECT]
D) Quaternary structure only
Rationale: Tertiary structure involves interactions between R-groups, including hydrophobic
interactions, hydrogen bonds, ionic bonds, and disulfide bridges. Primary structure is the amino
