2025 Final Exam LATEST
1. A patient in respiratory distress and is breathing 33 breaths per minute.
Which ABG value is consistent with the clinical scenario?
PCO2 15
pH 7.30
pH 7.45
O2 sat 100%
ANS: A patient who is breathing 33 breaths per minute is hyperventilating and
blowing off CO2; therefore the PCO2 level will be low. The patient will most likely
experience a respiratory alkalosis and the two pH values provided are not consistent
with this diagnosis.
2. A patient has a sodium level of 115 mEq/L and is disoriented and lethargic.
Which pathological process best explains this patient's symptoms?
a. The action potential has become hyperpolarized.
b. Water has shifted into the neurons and caused them to swell.
c. Water has shifted into the vascular space and dehydrated the neurons.
,d. The action potential has become hypopolarized.
ANS: b. The cause of neurologic symptoms associated with a sodium imbalance
is directly related to fluid shifting into or out of the neurons of the brain. With a
serum sodium of 115 mEq/L, water shifts into the neurons and causes them to
swell. Hypernatremia causes water to shift out of the cell into the intravascular
space and causes the neurons to become dehydrated. An alteration in the action
potential is not seen with sodium imbalances.
3. A patient experiencing dehydration should be monitored for which elec-
trolyte imbalance?
a. Hyperkalemia
b. Hypocalcemia
c. Hypercalcemia
d. Hyponatermia
ANS: a. Serum osmolality is increased during times of dehydration. An elevated
serum osmolality will pull potassium into the intravascular space from the
intracellular space and cause a rise in serum potassium.
4. A married couple presents to your office for genetic counseling. The hus-
band has an autosomal recessive disease and his wife has a heterozygous
genotype for the disease. They ask you, What is the chance that our baby will
have the disease? Which of the following answers is correct?
25%
50%
75%
100%
ANS: A chromosome is a package of material located inside the cell nucleus
which is made of proteins and a single molecule of DNA. There are 23 pairs of
,chromosomes in each human cell for a total of 46 chromosomes. Chromosomes
are separated into two identical sets during mitosis or meiosis. This provides a set
, of chromosomes to each daughter cell which results from cell division. This process
is responsible for the transfer of genetic information to the daughter cells. The first
22 pairs of chromosomes are known as autosomes. The 23rd pair of chromosomes
is the pair which contains the genetic information for gender. This pair contains
the genetic information which delineates between the male and female genders.
Females have two X chromosomes (XX) and males have an XY chromosome pair.
Autosomal chromosomes are said to be autologous. This means they do not carry
genetic information pertaining to gender. Autosomal genetic diseases are carried
on the first 22 pairs of chromosomes. Sex-linked diseases are only carried on
the 23rd pair of chromosomes. The autosomal chromosomes are nearly identical
to one another and are considered homologous to one another. Each autosomal
chromosome in a pair carries identical genes. These two genes are known as alleles.
The alleles occupy the same site on each partner of the chromosome pair and
code for the same genetic trait or physiologic function. Alleles can be dominant or
recessive. One allele may be dominant and the other recessive, or they both may be
dominant or both recessive. The dominant alleles' genetic code will always manifest
in the individual's phenotype. The information in the recessive allele is typically not
expressed in the phenotype unless both alleles are recessive. For the purpose of
clarity in use, the dominant gene is assigned a capital letter and the recessive gene
is assigned a lower case letter. Any letter is okay to use but make sure you use the
same letter for the genotype - for example, "Bb or aa." The term homozygous refers
to a pair of alleles which are either both dominant or recessive. For example, "BB
or bb" are said to be homozygous because the alleles are either both dominant or
recessive. An allele pair in which one is dominant and one is recessive is said to be
heterozygous. In autosomal recessive disorders both alleles on the chromosome
are affected by the genetic aberration. If only one recessive gene is affected by
the genetic aberration then the person is said to be a carrier and will not have the
phenotypic expression of the disease. The healthy, recessive allele will compensate
for the allele which is affected by the genetic aberration. The carrier can pass the
trait but does not have the genetic disease. In an autosomal dominant disorder the
dominant gene is the only gene that has to be affected by the genetic aberration in
order to have the phenotypic expression of the disease. A healthy recessive allele
cannot compensate for a diseased dominant allele. In order to answer this question