QUESTION- 1
Types of Epithelium
QUESTION-2
GAP JXN
Zonula adherens
Neural tube defects
(NTD)
In the apical part of the cells, the actin filament bundles contract, narrowing the cells at their apical
ends. The position of the zonula adherens, forming a contractile ring around the circumference of the
cell, coupled with the contractile nature of the actin microfilament bundles is ideal for regulating
morphogenetic changes.
Blistering disease (genetic defects in
desmosomal proteins )
 Pemphigus vulgaris or
 Pemphigus foliaceus
Bullous pemphigoid
Antibodies against
hemidesmosome results
in Bullous pemphigoid
Q
Which component of an intercalated disc
provides an attachment site for actin
filaments in cardiac muscle?
A. Sarcoplamic reticulum
B. Zonula occludens
C. Fascia adherens
D. Gap junction
E. Tight junction
Q
Which of the following functions in metabolic
coupling between adjacent cells?
A. Tight junction
B. Desmosomes
C. Gap junction
D. Zonula adherens
E. hemidesmosomes
Q
Your patient has a deficiency in the ATPase motor
protein dynein. Which of the following would
most likely be seen in the patient?
A. Anemia due to destruction of multiple misshaped RBCs by the spleen
B. Dizziness and sensorineural hearing deficits
C. Decreased absorption of nutrients by duodenal
columnar epithelial cells
D. Immotile sperm
E. An increase in glial fibrillary acidic protein in
astrocytes
Structure of cilia
-nine + two microtubules _ axoneme
-- organised from basal body
CLINICAL CORRELATION
An 11-year-old boy presents with ciliary dyskinesia, sinusitis, and
bronchiectasis. He has had persistent infections and otitis media since
birth. A PA radiograph shows dextrocardia, and he has a negative saccharin
test. In the cross-section of the cilium shown below, which of the following
is primarily affected in this disorder?
a. Structure A
b. Structure B
c. Structure C
d. Structure D
e. Structure E
A male child is born with an absence of the normal structure labeled
between the arrows; inclusions of that structure are found within the cells in the
photomicrograph. He presents with refractory diarrhea and is chronically
dependent on parenteral nutrition. What is the primary function of the structure
labeled between the arrows in the photomicrograph below?
a. Extensive movement of substances over cell surfaces
b. Increase in surface area for absorption
c. Cell motility
d. Transport of intracellular organelles through the cytoplasm
e. Stretch
Question
 A mother brings her son to the pediatrics clinic. The child
rapidly developed extensive blistering of the skin shortly
after birth.
 He has painful erosions of the oral mucosa and has refused
ingestion.
 He has also had a history of recurrent infections, with sepsis,
on one occasion. Antigen mapping of a skin biopsy shows a
split within the lamina lucida of the epidermal basement
membrane, and junctional epidermolysis bullosa (JEB) was
the diagnosis.
 In which specific layer of the accompanying electron
micrograph (next slide) would you expect to see the
disruption?
Question
 A mother brings her son to the pediatrics clinic. The child
rapidly developed extensive blistering of the skin shortly
after birth.
 He has painful erosions of the oral mucosa and has refused
ingestion.
 He has also had a history of recurrent infections, with sepsis,
on one occasion. Antigen mapping of a skin biopsy shows a
split within the lamina lucida of the epidermal basement
membrane, and junctional epidermolysis bullosa (JEB) was
the diagnosis.
 In which specific layer of the accompanying electron
micrograph (next slide) would you expect to see the
disruption?
Epidermolysis bullosa blistering of skin
Q
Which glycoprotein functions to bind cells at a
hemidesmosome to an underlying basal
lamina?
A. Entactin
B. Heparin sulphate
C. Fibronectin
D. Integrin
E. tenascin
A 48-year-old man has hepatic cancer that is unresponsive to
standard therapy. He enrolls in a clinical study of a novel
chemotherapeutic agent that, as a side effect, blocks kinesin, a
component of the cellular microtubular transport system. One
week later, he develops skeletal muscle weakness. An
alteration in which of the following components of the
neuromuscular junction is the most likely cause of the muscle
weakness?
(A) A decrease in the number of postsynaptic neurotransmitter
receptors
(B) A decrease in the number of presynaptic neurotransmitter
vesicles
(C) A decrease in the presynaptic neuron calcium permeability
(D) Impaired α-motoneuron action potential conduction
(E) Impaired skeletal muscle action potential conduction
A new drug is developed that prevents the
demyelinization occurring in the progress of
multiple sclerosis. The drug protects the cells
responsible for the synthesis and maintenance of
myelin in the central nervous system. These cells are
most likely which of the following?
(A) Astrocyte
(B) Ependymal cell
(C) Microglial cell
(D) Oligodendrocyte
(E) Schwann cell
Defects in the production of kinesin might
result in
A. Vertigo
B. Inability of axons to transport substances in
the anterograde direction
C. Respiratory distress
D. Inability of axon terminals to take up calcium
E. Reduced fertility
Axons found around the area indicated by the
arrow in the figure above are myelinated by
A. astrocytes
B. dorsal root ganglion cells
C. microglia
D. oligodendrocytes
E. Schwann cells
An oophorectomized monkey is treated with high doses of
estrogen. Which of the following changes is most likely to
occur in the endometrium after 1 year of treatment?
(A) Atrophy
(B) Hyperplasia
(C) Hypertrophy
(D) Hypoplasia
(E) Metaplasia
2. Which of the following muscle cell components helps spread
the depolarization of the muscle cell membranes throughout
the interior of muscle cells?
(A) Actin
(B) Myosin
(C) T tubule
(D) Tropomyosin
(E) Troponin
(F) Z disk
An experiment is conducted in which the mitochondrial
content of various tissues is studied. It is found that the
mitochondrial content is directly proportional to the amount
of
energy one cell is required to generate and expend. The
mitochondrial content is most likely greatest in which of the
following types of cells?
(A) Cardiac muscle cells
(B) Chondrocytes
(C) Endothelial cells
(D) Epidermal cells
(E) Hepatocytes
(F) Osteocytes
(G) White adipocytes
Which of the following is the correct sequence of events in the initiation of
contraction of a skeletal muscle fiber?
Depolarizati Conformatio
on of
nal change in
sarcolemma troponintropomyosin
complex
Release of
Ca2+ from
sarcoplasmi
c reticulum
Propagatio
n into
transverse
tubules
Acetylcholi
ne binding
to receptors
A
1
2
3
4
5
B
2
5
4
3
1
C
3
5
2
4
1
D
4
2
5
3
1
E
5
3
4
1
2
A pathologist uses monoclonal antibodies
against several intermediate filament proteins
and finds that a tumor section stains positive for
cytokeratin only. The tumor most likely
originated from which of the following tissues?
(A) Connective
(B) Epithelial
(C) Glial
(D) Muscle
(E) Neural