Practice Questions & Verified Answers
1. What specific area of the sarcomere decreases in size during muscle
contraction?
H zone
I band
Z line
A band
2. If a patient has a deficiency in cholesterol synthesis, which hormone's
production would be most directly affected, and why?
Testosterone, because it is a protein hormone.
Epinephrine, because it is derived from amino acids.
Cortisol, because it is a peptide hormone.
Aldosterone, because it is a steroid hormone derived from
cholesterol.
3. What is the primary role of surfactant in the lungs?
Prevent alveolar collapse
Regulate blood pH
Facilitate gas exchange
Enhance oxygen transport
4. What type of molecule is produced during the formation of both
glycosidic and phosphodiester bonds?
NADH
, CO2
ATP
H2O
5. What type of root system is characterized by a single taproot with
branching?
Adventitious root
Fibrous root
Lateral root
Taproot
6. The following graph shows the oxygen dissociation curves of
hemoglobin from an adult sheep and a fetal sheep. Which one of the
following statements describes the difference in the behavior of the two
types of hemoglobin?
Adult hemoglobin has higher affinity than fetal hemoglobin
Adult hemoglobin cannot carry as much oxygen as fetal
hemoglobin
Cannot be answered based on given information
, Fetal hemoglobin has higher affinity for oxygen than adult
hemoglobin
Fetal hemoglobin cannot carry as much oxygen as adult
hemoglobin
7. What kind of cell junction allows molecules to pass directly from the
cytoplasm of one animal cell to another?
Gap junctions
Integrins
Desmosomes
Tight junctions
Plasmodesmata
8. In a scenario where a patient has a compromised immune system, which
type of immune cell would be crucial for enhancing both specific and
non-specific immune responses?
Macrophages
Major histocompatibility complex class II
B cells
Cytotoxic T cells
9. Describe the role of the neural tube in the development of the spinal
cord.
The neural tube is responsible for the formation of the heart.
The neural tube develops into the digestive system.
The neural tube is the embryonic structure that develops into
the central nervous system, including the spinal cord.
The neural tube forms the outer layer of the skin.
, 10. Describe the role of the smooth endoplasmic reticulum in cellular
metabolism.
The smooth endoplasmic reticulum synthesizes proteins and
ribosomal RNA.
The smooth endoplasmic reticulum is responsible for packaging
proteins for secretion.
The smooth endoplasmic reticulum generates ATP for cellular
energy.
The smooth endoplasmic reticulum is involved in the synthesis
of lipids and detoxification processes.
11. Describe the changes that occur in the sarcomere during muscular
contraction, particularly focusing on the H zone.
The H zone remains unchanged while the Z lines move closer
together.
During muscular contraction, the H zone decreases in size as
the actin filaments slide over the myosin filaments.
The H zone increases in size due to the thickening of myosin
filaments.
The H zone disappears completely during relaxation of the
muscle.
12. If a mutation caused erythrocytes to develop a nucleus, what potential
impact could this have on their susceptibility to viral infections?
Enhanced ability to fight infections
Decreased susceptibility to viral infections
Increased susceptibility to viral infections
No impact on susceptibility