NUR242 MED SURG EXAM 5 2026 FULL
PREPARATION WITH CORRECT ANSWERS
◉ serum osmolality Answer: measures the concentration of solutes
to water
keeps water and electrolytes in homeostasis in the blood
can be monitored by determining the serum osmolality of the blood
◉ What is a normal serum osmolality level? Answer: 285-295
mOsm/kg
◉ As body water _____, the concentration of solutes increases and
leads to a(n) _____ in serum osmolality. Answer: decreases
increase
◉ _____% of the water in our body is in the intracellular space, _____%
is in the interstitial space, and _____% is in the intravascular space.
Answer: 67
25
8
,◉ osmosis Answer: movement of water across a semi-permeable
membrane
moves on a high-to-low gradient
◉ thirst Answer: results from nerve centers in the brain being
stimulated when the body needs water
◉ vasopressin Answer: aka antidiuretic hormone (ADH)
an antidiuretic hormone secreted by the pituitary gland to conserve
water
stimulates the kidneys to excrete less urine
◉ When serum osmolality _____, the hypothalamus stimulates the
posterior pituitary to release ADH. Answer: rises
◉ ADH Answer: acts on the kidneys to increase the reabsorption of
water, decreasing the excretion of urine, and increasing the fluid
volume of the body
,◉ diffusion Answer: the movement of solutes, such as electrolytes,
from an area of high concentration to an area of low concentration
passive process that does not require energy
◉ active transport Answer: the process to move solutes from an area
of lower concentration to one of higher concentration
involves the use of energy (is not passive)
◉ What things can cause electrolyte imbalance? (5) Answer: -
dehydration
- history of heart, liver, or kidney disorders
- incorrect IV fluids or feedings
- medications
- overhydration
◉ potassium expected range (don't need to get it exactly just know
its around this range) Answer: 3.5-5 mEq/L
◉ sodium expected range (don't need to get it exactly just know its
around this range) Answer: 136-145 mEq/L
, ◉ calcium expected range (don't need to get it exactly just know its
around this range) Answer: 9-10.5 mg/dL
◉ magnesium expected range (don't need to get it exactly just know
its around this range) Answer: 1.3-2.1 mEq/L
◉ What is the function of potassium? (2) Answer: - helps with nerve
and muscle cell function while
- plays an important role in the muscle cells in the heart
◉ hypokalemia Answer: low potassium levels
◉ List 4 potential causes of hypokalemia: Answer: - alcohol use
- loss of potassium from the kidneys or GI tract
- metabolic alkalosis
- potassium-wasting diuretics
◉ List 4 signs of hypokalemia: Answer: - cardiac arrhythmias
- constipation
- fatigue
- muscle weakness
PREPARATION WITH CORRECT ANSWERS
◉ serum osmolality Answer: measures the concentration of solutes
to water
keeps water and electrolytes in homeostasis in the blood
can be monitored by determining the serum osmolality of the blood
◉ What is a normal serum osmolality level? Answer: 285-295
mOsm/kg
◉ As body water _____, the concentration of solutes increases and
leads to a(n) _____ in serum osmolality. Answer: decreases
increase
◉ _____% of the water in our body is in the intracellular space, _____%
is in the interstitial space, and _____% is in the intravascular space.
Answer: 67
25
8
,◉ osmosis Answer: movement of water across a semi-permeable
membrane
moves on a high-to-low gradient
◉ thirst Answer: results from nerve centers in the brain being
stimulated when the body needs water
◉ vasopressin Answer: aka antidiuretic hormone (ADH)
an antidiuretic hormone secreted by the pituitary gland to conserve
water
stimulates the kidneys to excrete less urine
◉ When serum osmolality _____, the hypothalamus stimulates the
posterior pituitary to release ADH. Answer: rises
◉ ADH Answer: acts on the kidneys to increase the reabsorption of
water, decreasing the excretion of urine, and increasing the fluid
volume of the body
,◉ diffusion Answer: the movement of solutes, such as electrolytes,
from an area of high concentration to an area of low concentration
passive process that does not require energy
◉ active transport Answer: the process to move solutes from an area
of lower concentration to one of higher concentration
involves the use of energy (is not passive)
◉ What things can cause electrolyte imbalance? (5) Answer: -
dehydration
- history of heart, liver, or kidney disorders
- incorrect IV fluids or feedings
- medications
- overhydration
◉ potassium expected range (don't need to get it exactly just know
its around this range) Answer: 3.5-5 mEq/L
◉ sodium expected range (don't need to get it exactly just know its
around this range) Answer: 136-145 mEq/L
, ◉ calcium expected range (don't need to get it exactly just know its
around this range) Answer: 9-10.5 mg/dL
◉ magnesium expected range (don't need to get it exactly just know
its around this range) Answer: 1.3-2.1 mEq/L
◉ What is the function of potassium? (2) Answer: - helps with nerve
and muscle cell function while
- plays an important role in the muscle cells in the heart
◉ hypokalemia Answer: low potassium levels
◉ List 4 potential causes of hypokalemia: Answer: - alcohol use
- loss of potassium from the kidneys or GI tract
- metabolic alkalosis
- potassium-wasting diuretics
◉ List 4 signs of hypokalemia: Answer: - cardiac arrhythmias
- constipation
- fatigue
- muscle weakness
