ANSWERS AND RATIONALES
1. The major cause of Parkinson's disease is _____.
A) Loss of serotonin-producing neurons
B) Overabundance of serotonin-producing neurons
C) Loss of dopamine-producing neurons ✓
D) Overabundance of dopamine-producing neurons
Rationale: Parkinson's disease is primarily caused by the progressive
degeneration and loss of dopamine-producing neurons in the substantia
nigra region of the brain. This loss leads to decreased dopamine levels,
which results in the characteristic motor symptoms such as tremors,
rigidity, bradykinesia, and postural instability.
2. What is the primary characteristic of multiple sclerosis (MS)?
A) Progressive loss of myelin sheath around nerves ✓
B) Destruction of neurons in the hippocampus
C) Increased sensitivity to stimuli
D) Overproduction of neurotransmitters
Rationale: Multiple sclerosis is an autoimmune disease characterized by
demyelination—the progressive destruction of the myelin sheath that
surrounds and protects nerve fibers in the central nervous system. This
,damage disrupts nerve signal transmission, leading to various
neurological symptoms.
3. What is a characteristic symptom of rheumatoid arthritis?
A) Joint stiffness that is worse in the evening
B) Joint pain with morning stiffness lasting longer than 30 minutes ✓
C) Skin rashes and blisters
D) Joint deformity only in the late stages
Rationale: Rheumatoid arthritis is characterized by inflammatory joint
pain with prolonged morning stiffness typically lasting more than 30
minutes. This morning stiffness is a key diagnostic feature that
distinguishes RA from osteoarthritis, where morning stiffness is usually
shorter in duration.
4. Which of the following best describes the initial, major neuronal
defect (loss) in Parkinson's disease?
A) Loss of dopamine secreting neurons ✓
B) Loss of GABA secreting neurons
C) Loss of serotonin secreting neurons
D) Loss of acetylcholine secreting neurons
Rationale: The primary neuronal defect in Parkinson's disease is the loss
of dopamine-secreting neurons in the substantia nigra pars compacta.
This dopamine deficiency in the basal ganglia leads to the movement
disorders characteristic of the disease.
, 5. Describe how marasmus differs from kwashiorkor in terms of
physical characteristics.
A) Marasmus involves increased fat stores, whereas kwashiorkor does
not
B) Marasmus and kwashiorkor present the same physical characteristics
C) Marasmus leads to high serum albumin levels, unlike kwashiorkor
D) Marasmus is characterized by severe muscle wasting and loss of
subcutaneous fat, while kwashiorkor is characterized by edema and a
large abdomen ✓
Rationale: Marasmus results from overall calorie deficiency and
presents with severe muscle wasting, loss of subcutaneous fat, and an
emaciated appearance. Kwashiorkor results from protein deficiency
despite adequate calorie intake and is characterized by edema, ascites
(large abdomen), and fatty liver. Serum albumin is low in kwashiorkor
but may be normal in marasmus.
6. Which vitamin is frequently lacking in patients suffering from
chronic alcoholism?
A) Vitamin B12
B) Vitamin A
C) Vitamin D
D) Folate ✓
Rationale: Chronic alcoholism commonly leads to folate deficiency due
to poor dietary intake, impaired absorption, and increased excretion.
Folate deficiency can result in macrocytic anemia and other
complications. While thiamine deficiency (Wernicke-Korsakoff