SNC4M Exam Review UPDATED
QUESTIONS AND CORRECT ANSWERS
What is the definition of homeostasis - CORRECT ANSWER The "internal balance" or narrow
range of conditions a living thing must maintain to be healthy and function efficiently.
How is body temperature defined? - CORRECT ANSWER The balance between heat loss
(sweating, breathing, & excretion) and heat produced through digestion and muscle contraction
What is the standard baseline for human body temperature - CORRECT ANSWER Approx.
98.6 F or 37 C
Define hyperthermia (fever) and hypothermia based on their temperature thresholds - CORRECT
ANSWER Hyperthermia/Fever: A temperature above 101 DF, often in response to infection
Hypothermia: A temperature below 96 DF due to prolonged cold exposure
What is heart rate and what is its healthy adult range? - CORRECT ANSWER It's the number
of times the heart beats in one minute. The healthy adult range is 60-100 beats per minute
What are the four common sites used to measure a pulse? - CORRECT ANSWER The wrist
(radical), neck (carotid), inner elbow (brachial), and heart (apical)
What is the respiratory rate and what is its healthy adult range at rest? - CORRECT ANSWER
The number of breaths taken per minute. The healthy adult range is 12-20 breaths per minute at
rest.
List the five breathing sounds observed with a stethoscope and what they indicate. - CORRECT
ANSWER Clear: Unobstructed breathing.
Wheeze: Obstructed breathing.
Stridor: A blockage in the trachea.
Stertor: Snoring or fluid presence.
Crackle: Inflammation.
,Define systolic and diastolic blood pressure, including their standard millimeter of mercury (mmHg)
ranges. - CORRECT ANSWER Systolic: Peak pressure during heart contraction, standardly
90-120 mmHg.
Diastolic: Lowest pressure during heart relaxation, standardly 60-80 mmHg.
Compare hypertension and hypotension by their numeric thresholds and common causes. -
CORRECT ANSWER Hypertension (>140/90): Linked to obesity and high-sodium diets.
Hypotension (<100/60): Can be caused by blood loss or infection.
What does Oxygen Saturation (SpO2) measure and what is its standard range? - CORRECT
ANSWER It measures the percentage of red blood cells saturated with oxygen. The standard
range is 95-100%.
How does a pulse oximeter estimate oxygen saturation through the skin? - CORRECT ANSWER
It utilizes red light at 660nm and infrared light at 940nm.
What is the general biological classification of blood? - CORRECT ANSWER Blood is a
connective tissue where cells are suspended in a liquid extracellular matrix known as plasma.
Describe the anatomical structure of erythrocytes (red blood cells) and why they are formed this way.
- CORRECT ANSWER They are structured as biconcave discs that completely lack a nucleus,
endoplasmic reticulum (ER), or mitochondria in order to maximize internal space for carrying
hemoglobin.
Where does erythrocyte production occur and what mechanism controls it? - CORRECT ANSWER
Production occurs in the red bone marrow. It is controlled by the hormone erythropoietin via a
negative feedback loop triggered by low oxygen levels.
What is the life cycle duration of a red blood cell, and how are they cleared from the body? -
CORRECT ANSWER They live for about 120 days and are recycled in the liver and spleen by
specialized cells called macrophages.
What is the normal count range for leukocytes (white blood cells)? - CORRECT ANSWER
3,500 to 10,500 cells per microliter.
, Name the two major structural categories of leukocytes and their respective cell types. - CORRECT
ANSWER Granulocytes: Neutrophils, eosinophils, and basophils.
Agranulocytes: Monocytes and lymphocytes.
Differentiate between leukocytosis and leukopenia, noting potential causes. - CORRECT ANSWER
Leukocytosis ($>10,500$ cells/$\mu L$): Indicates an active infection or leukemia.
Leukopenia ($<3,500$ cells/$\mu L$): Can be caused by conditions like AIDS or the flu.
What are thrombocytes and what is their physiological function? - CORRECT ANSWER They
are cell fragments, also called platelets, that help close breaks in blood vessels and play a central role
in blood clotting.
What is blood plasma and what are its three major functional proteins? - CORRECT ANSWER
Plasma is the liquid portion of blood that transports gases/nutrients and regulates pH. Its major
proteins are:
Albumins: Regulate osmotic pressure.
Globulins: Provide immunity.
Fibrinogen: Aids in blood clotting.
How do X-Rays create medical images and what health risks do they carry? - CORRECT ANSWER
They shoot electromagnetic rays through the body; denser structures like bone block the rays
and appear white, while softer parts appear dark. Risks include DNA mutations and cancer.
Explain how Computed Tomography (CT) scans work and what tissues they visualize best. -
CORRECT ANSWER They combine X-ray images captured from multiple angles to construct
cross-sectional imaging "slices". They are best suited for evaluating bones and organs.
How do Magnetic Resonance Imaging (MRI) scans function and what tissues are they best suited to
view? - CORRECT ANSWER They utilize magnetic fields and radio waves, which are forms
of non-ionizing radiation. They are best suited for visualizing muscles, ligaments, and soft tissues.
Describe a Positron Emission Tomography (PET) scan and its typical cost. - CORRECT ANSWER
It is a nuclear medicine diagnostic procedure that measures metabolic activity to generate 3D
anatomical images. It carries a high cost of approximately $3,200.
QUESTIONS AND CORRECT ANSWERS
What is the definition of homeostasis - CORRECT ANSWER The "internal balance" or narrow
range of conditions a living thing must maintain to be healthy and function efficiently.
How is body temperature defined? - CORRECT ANSWER The balance between heat loss
(sweating, breathing, & excretion) and heat produced through digestion and muscle contraction
What is the standard baseline for human body temperature - CORRECT ANSWER Approx.
98.6 F or 37 C
Define hyperthermia (fever) and hypothermia based on their temperature thresholds - CORRECT
ANSWER Hyperthermia/Fever: A temperature above 101 DF, often in response to infection
Hypothermia: A temperature below 96 DF due to prolonged cold exposure
What is heart rate and what is its healthy adult range? - CORRECT ANSWER It's the number
of times the heart beats in one minute. The healthy adult range is 60-100 beats per minute
What are the four common sites used to measure a pulse? - CORRECT ANSWER The wrist
(radical), neck (carotid), inner elbow (brachial), and heart (apical)
What is the respiratory rate and what is its healthy adult range at rest? - CORRECT ANSWER
The number of breaths taken per minute. The healthy adult range is 12-20 breaths per minute at
rest.
List the five breathing sounds observed with a stethoscope and what they indicate. - CORRECT
ANSWER Clear: Unobstructed breathing.
Wheeze: Obstructed breathing.
Stridor: A blockage in the trachea.
Stertor: Snoring or fluid presence.
Crackle: Inflammation.
,Define systolic and diastolic blood pressure, including their standard millimeter of mercury (mmHg)
ranges. - CORRECT ANSWER Systolic: Peak pressure during heart contraction, standardly
90-120 mmHg.
Diastolic: Lowest pressure during heart relaxation, standardly 60-80 mmHg.
Compare hypertension and hypotension by their numeric thresholds and common causes. -
CORRECT ANSWER Hypertension (>140/90): Linked to obesity and high-sodium diets.
Hypotension (<100/60): Can be caused by blood loss or infection.
What does Oxygen Saturation (SpO2) measure and what is its standard range? - CORRECT
ANSWER It measures the percentage of red blood cells saturated with oxygen. The standard
range is 95-100%.
How does a pulse oximeter estimate oxygen saturation through the skin? - CORRECT ANSWER
It utilizes red light at 660nm and infrared light at 940nm.
What is the general biological classification of blood? - CORRECT ANSWER Blood is a
connective tissue where cells are suspended in a liquid extracellular matrix known as plasma.
Describe the anatomical structure of erythrocytes (red blood cells) and why they are formed this way.
- CORRECT ANSWER They are structured as biconcave discs that completely lack a nucleus,
endoplasmic reticulum (ER), or mitochondria in order to maximize internal space for carrying
hemoglobin.
Where does erythrocyte production occur and what mechanism controls it? - CORRECT ANSWER
Production occurs in the red bone marrow. It is controlled by the hormone erythropoietin via a
negative feedback loop triggered by low oxygen levels.
What is the life cycle duration of a red blood cell, and how are they cleared from the body? -
CORRECT ANSWER They live for about 120 days and are recycled in the liver and spleen by
specialized cells called macrophages.
What is the normal count range for leukocytes (white blood cells)? - CORRECT ANSWER
3,500 to 10,500 cells per microliter.
, Name the two major structural categories of leukocytes and their respective cell types. - CORRECT
ANSWER Granulocytes: Neutrophils, eosinophils, and basophils.
Agranulocytes: Monocytes and lymphocytes.
Differentiate between leukocytosis and leukopenia, noting potential causes. - CORRECT ANSWER
Leukocytosis ($>10,500$ cells/$\mu L$): Indicates an active infection or leukemia.
Leukopenia ($<3,500$ cells/$\mu L$): Can be caused by conditions like AIDS or the flu.
What are thrombocytes and what is their physiological function? - CORRECT ANSWER They
are cell fragments, also called platelets, that help close breaks in blood vessels and play a central role
in blood clotting.
What is blood plasma and what are its three major functional proteins? - CORRECT ANSWER
Plasma is the liquid portion of blood that transports gases/nutrients and regulates pH. Its major
proteins are:
Albumins: Regulate osmotic pressure.
Globulins: Provide immunity.
Fibrinogen: Aids in blood clotting.
How do X-Rays create medical images and what health risks do they carry? - CORRECT ANSWER
They shoot electromagnetic rays through the body; denser structures like bone block the rays
and appear white, while softer parts appear dark. Risks include DNA mutations and cancer.
Explain how Computed Tomography (CT) scans work and what tissues they visualize best. -
CORRECT ANSWER They combine X-ray images captured from multiple angles to construct
cross-sectional imaging "slices". They are best suited for evaluating bones and organs.
How do Magnetic Resonance Imaging (MRI) scans function and what tissues are they best suited to
view? - CORRECT ANSWER They utilize magnetic fields and radio waves, which are forms
of non-ionizing radiation. They are best suited for visualizing muscles, ligaments, and soft tissues.
Describe a Positron Emission Tomography (PET) scan and its typical cost. - CORRECT ANSWER
It is a nuclear medicine diagnostic procedure that measures metabolic activity to generate 3D
anatomical images. It carries a high cost of approximately $3,200.
