CHEM 301/CHEM301 BIOCHEM MIDTERM Exam Latest Updated 2024/2025 Questions and Answers with complete solution; Athabasca University

CHEM 301/CHEM301 BIOCHEM MIDTERM Exam
Latest Updated 2024/2025 Questions and Answers with
complete solution; Athabasca University
1. UNIT 1 Define "biochemistry." the study of the building blocks, or mol-
ecules, of life and how these interact in
the processes that occur in living organ-
isms.

2. Name the major classes of - proteins (amino acids)
biomolecules, and identify the - carbohydrates or polysaccharides
atoms most commonly found in (monosaccharides or simple sugars)
each class. - lipids (fatty acids)
- nucleic acids (nucleotides).

3. Define "metabolic pathway." linked series of chemical reactions oc-
curring within a cellular processes

4. List the 6 elements that make up CHNO CP
99% of living cells
carbon, hydrogen, nitrogen, oxygen, cal-
cium, and phosphorus.

5. Identify some applications of bio- medicine (causes and cures of dis-
chemistry. eases)
nutrition (maintain health and wellness,
nutritional deficiencies)
agriculture (soil and fertilizers)

6. What are the four elements most carbon (C), oxygen (O), hydrogen (H)
commonly found in biomole- and nitrogen (N)
cules?

7. Describe the organization of Eu-
karyotic Cells and Prokaryotic
Cells



8. How does the composition of the The earth's crust is mostly composed
earth's crust and living cells dif- of Oxygen, Aluminum, Silicon, and Iron.
fer? Living cells are mostly composed of C,


,CHEM 301/CHEM301 BIOCHEM MIDTERM Exam
Latest Updated 2024/2025 Questions and Answers with
complete solution; Athabasca University
H N, O.






, Two elements found in the earth's crust,
Si and Al, are not found in living matter.

9. What is the function of the follow- Golgi apparatus - protein assembly and
ing organelles? secretion
Golgi apparatus, lysosome, ribo- lysosomes - digestion of proteins
somes, mitochondria, cytoskele- ribosomes - synthesize proteins
ton mitochondria - synthesize ATP
cytoskeleton - provides support and
structure to the cell.

10. Where are sugars and fats di- Sugars and fats are partially digested in
gested in the cell? the cytoplasm. They are then transport-
ed into the mitochondria, where they are
converted into ATP.

11. List the differences between
prokaryotic and eukaryotic cells
in terms of the following:
nucleus
internal structures
cytoskeleton
DNA organization
Reproduction

12. Explain DNA difference of eukaryotic DNA: linear and packaged
prokaryotic and eukaryotic with histones

prokaryotic DNA is circular and nega-
tively supercoiled and is not associated
with histones.

13. Explain how the chemical prop- Water is a universal solvent, Mosaic
erties of water make it the ideal structure, Hydrogen bonds, Surface ten-
biological solvent. sion

it is capable of dissolving more sub-
stances than any other liquid. It is polar



, 14. Describe hydrogen bonds g g Dipole-dipole attraction which occurs g g g


(H bonds).
g when a hydrogen atom bonded to a
g g g g g g g


strongly electronegative atom exists in
g g g g g


the vicinity of another electronegative
g g g g g


atom with a lone pair of electrons
g g g g g g g




15. Using the concept of H bonding,hydrogen bonds btwn water molecules,
g g g g g g g g


explain how small items that are form a lattice of water molecules, which
g g g g g g g g g g g


denser than water (e.g., a fine
g g is strong and flexible. Creates a high sur-
g g g g g g g g g g g g


needle or a water bug) can re-
g g face tension. As a result, this molecule
g g g g g g g g g g g g


main on the surface instead of at the surface tends to be pulled into the
g g g g g g g g g g g g g g g


sinking.
g bulk of the liquid and thus minimizes the g g g g g g g g


surface area of a liquid g g g g g




16. Describe an amphiphilic mole-g g g A chemical compound possessing both
g g g g


cule
g hydrophilic (water-loving, polar) and
g g g g


lipophilic (fat-loving) properties
g g g




17. What is a buffer and why are
g g g g g g a molecule or molecular system that
g g g g g


buffers important?
g g acts to resist changes in pH (provide or
g g g g g g g g


absorb protons as needed). Important
g g g g g


in living systems for maintaining home-
g g g g g g


ostasis.
g




18. Why is pH important for mole-
g g g g g Changing charges on biological mole- g g g g


cules, in particular proteins?
g g g g cules due to pH changes can affect how
g g g g g g g g


these molecules function.
g g g




19. Define the terms "acid" and
g g g g Acid is a substance with protons that can
g g g g g g g


"base."
g dissociate when dissolved in water.
g g g g g


Base is a substance that can absorb
g g g g g g


protons when dissolved in water.
g g g g g




4 g/
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