Circulatory System

Which of the following structures is responsible for protecting, lubricating, and stabilizing the heart?

A. 

Pericardium

B. 

Atria

C. 

Ventricle

D. 

Septum

E. 

Aorta

Pericardium

Which of the following heart structures typically contains deoxygenated blood?

A. 

Left ventricle

B. 

Aorta

C. 

Right atrium

D. 

Pulmonary vein

E. 

Left atrium

Right atrium

Which of the following structures prevents backflow of blood between the left atrium and ventricle?

A. 

Tricuspid valve

B. 

Pulmonary valve

C. 

Aortic valve

D. 

Mitral valve

Mitral valve/Bicuspid valve

Which of the following sequences correctly describes the order of valves that blood passes through as it flows through the heart?

A. 

Mitral valve → Aortic valve → Tricuspid valve → Pulmonary valve

B. 

Tricuspid valve → Pulmonary valve → Aortic valve → Mitral valve

C. 

Pulmonary valve → Tricuspid valve → Aortic valve → Mitral valve

D. 

Tricuspid valve → Pulmonary valve → Mitral valve → Aortic valve

E. 

Mitral valve → Tricuspid valve → Pulmonary valve → Aortic valve

Tricuspid valve → Pulmonary valve → Mitral valve → Aortic valve

All of the following animals are correctly paired with their number of heart chambers EXCEPT one. Which one is the EXCEPTION?

A. 

Monkey - 4

B. 

Hummingbird - 4

C. 

Crocodile - 3

D. 

Frog - 3

E. 

Salmon - 2

Crocodile - 3 - they have 4 chmabers

Which of the following best describes the primary function of capillaries?

A. 

Transport oxygenated blood at the highest pressure

B. 

Return deoxygenated blood to the heart

C. 

The main site for gas exchange between blood and tissues

D. 

Actively pump nutrients into the tissues

E. 

Synthesize proteins needed by tissues

The main site for gas exchange between blood and tissues

Which of the following structures brings blood to the right atrium?

A. 

Pulmonary veins

B. 

Tricuspid valve

C. 

Pulmonary arteries

D. 

Aorta

E. 

Superior vena cava

Superior vena cava

Which of the following sequences correctly describes the order of blood flow through the heart?

A. 

Right atrium → Left ventricle → Pulmonary circuit → Left atrium → Right ventricle

B. 

Right ventricle → Right atrium → Pulmonary circuit → Left atrium → Left ventricle

C. 

Right atrium → Right ventricle → Pulmonary circuit → Left atrium → Left ventricle

D. 

Right atrium → Right ventricle → Pulmonary circuit→ Left ventricle → Left atrium

E. 

Right atrium → Pulmonary circuit → Right ventricle → Left atrium → Left ventricle

Right atrium → Right ventricle → Pulmonary circuit → Left atrium → Left ventricle

Which of the following structures contains the lowest O₂ concentration?

A. 

Pulmonary arteries

B. 

Pulmonary veins

C. 

Aorta

D. 

Left Atrium

E. 

Right Atrium

Pulmonary arteries

Which of the following is the correct order of structures that blood passes through after leaving the aorta?

A. 

Pulmonary arteries → Capillaries → Pulmonary veins

B. 

Systemic arteries → Capillaries → Systemic veins

C. 

Right Atrium → Right Ventricle → Capillaries → Left Atrium → Left Ventricle

D. 

Left Atrium → Left Ventricle → Capillaries → Right Atrium → Right Ventricle

E. 

Systemic veins → Capillaries → Systemic arteries

Systemic arteries → Capillaries → Systemic veins

Which anatomical structure in the heart initiates the coordinated contraction of the cardiac muscles?

A. 

Atrioventricular node

B. 

Bundle of His

C. 

Purkinje fibers

D. 

Sinoatrial node

E. 

Aorta

Sinoatrial node

Which of the following is the correct order of the electrical conduction pathway within the heart?

A. 

AV node → SA node → Purkinje fibers → Bundle of His

B. 

SA node → AV node → Purkinje fibers → Bundle of His

C. 

SA node → AV node → Bundle of His → Purkinje fibers

D. 

Bundle of His → Purkinje fibers → AV node → SA node

E. 

AV node → SA Node → Bundle of His → Purkinje fibers

SA node → AV node → Bundle of His → Purkinje fibers

In an electrocardiogram (EKG), what does the ‘QRS’ complex represent?

A. 

Ventricular repolarization

B. 

Atrial repolarization

C. 

Ventricular depolarization

D. 

Atrial depolarization

E. 

Purkinje fiber repolarization

Ventricular depolarization

Which of the following would increase blood pressure?

A.

Decreasing the heart rate

B.

Decreasing the cardiac output

C.

Decreasing the stroke volume

D.

Decreasing the viscosity of the blood

E.

Decreasing the diameter of the blood vessels

Decreasing the diameter of the blood vessels - BP = cardiac output (CO) x systemic vascular resistance (SVR). Decreasing the diameter of the blood vessels would result in a higher SVR and increased blood pressure.

Which of the following is likely to occur as a result of a higher stroke volume?

A. 

Lower systemic vascular resistance

B. 

Increased cardiac output

C. 

Increased heart rate

D. 

Decreased blood pressure

E. 

Decreased heart rate

Increased cardiac output - The stroke volume (SV) is the total amount of blood that gets pushed out of the ventricles and is found using the equation SV = EDV (before contraction) – ESV (after contraction).

Cardiac output (CO) is the volume of blood discharged from both ventricles each minute. It is represented by the equation CO = SV x Heart Rate (contractions per minute).

All of the following are true of arterioles EXCEPT one. Which one is the EXCEPTION?

A. 

Carries oxygenated blood away from the heart

B. 

Have a smooth muscle layer

C. 

Can constrict and dilate

D. 

Regulate blood pressure

E. 

Have valves to prevent blood backflow

Have valves to prevent blood backflow

Which of the following blood vessels have the greatest total surface area and cross-sectional area?

A. 

Arteries

B. 

Veins

C. 

Arterioles

D. 

Capillaries

E. 

Venules

Capillaries

Which of the following best describes oncotic pressure?

A. 

The pressure exerted by proteins in the blood that helps maintain fluid balance

B. 

The high pressure of the fluid against the internal vessel walls resulting in filtration

C. 

The equilibrium pressure where there is no net movement

D. 

The pressure created by precapillary sphincters contracting

E. 

The pressure exerted by the red blood cells that help regulate filtration

The pressure exerted by proteins in the blood that helps maintain fluid balance

At the arteriole end of the capillaries, there is ___________ of fluid.

A. 

Increased oncotic pressure

B. 

No net movement

C. 

Net filtration

D. 

Decreased hydrostatic pressure

E. 

Net reabsorption

Net filtration

Which of the following best describes the function of precapillary sphincters?

A. 

Direct blood flow accords with the body’s needs

B. 

Prevent the backflow of blood from arteries to veins

C. 

Facilitate the exchange of oxygen and carbon dioxide in the lungs

D. 

Directly regulate blood pressure

E. 

Increases the heart rate by adjusting the flow of blood back to the heart

Direct blood flow accords with the body’s needs

Which of the following best describes the function of the placenta in fetal development?

A. 

Synthesizes essential amino acids for the fetus

B. 

Facilitates the exchange of nutrients, gasses, and waste between the mother and fetus

C. 

Provides oxygenation from the fetus for the maternal blood

D. 

Stores deoxygenated blood and waste for the fetus to recycle

E. 

Creates red blood cells for the fetus to develop

Facilitates the exchange of nutrients, gasses, and waste between the mother and fetus

If the foramen ovale fails to close long after birth, which of the following is most likely to occur?

A. 

Reduced blood flow to the lower body

B. 

Oxygenated blood will continue to bypass the liver

C. 

Increased blood flow to the lungs

D. 

Mixing of oxygenated and deoxygenated blood between atriums

E. 

Higher blood pressure in the veins

Mixing of oxygenated and deoxygenated blood between atriums

Which of the following structures allows fetal circulation to bypass the liver by connecting the umbilical vein to the inferior vena cava?

A. 

Ductus arteriosus

B. 

Umbilical artery

C. 

Ligamentum venosum

D. 

Foramen ovale

E. 

Ductus venosus

Ductus venosus

Which two structures are linked by the ductus arteriosus?

A. 

Umbilical vein and inferior vena cava

B. 

Right atrium and pulmonary artery

C. 

Pulmonary artery and left ventricle

D. 

Pulmonary artery and aorta

E. 

Right atrium and left atrium

Pulmonary artery and aorta

Which of the following structures carries waste and deoxygenated blood away from the fetus?

A. 

Umbilical artery

B. 

Kidneys

C. 

Ductus venosus

D. 

Umbilical Vein

E. 

Liver

Umbilical artery

Which of the following can be altered in order to effectively adjust blood pressure?

A. 

Number of cardiac muscle cells

B. 

Cell membrane composition

C. 

Increased platelet production

D. 

Diameter of nervous tissue in blood vessel walls

E. 

Blood volume

Blood volume - An increase in blood volume increases blood pressure, while a decrease lowers blood pressure.

All of the following would increase blood pressure EXCEPT one. Which one is the EXCEPTION?

A. 

Increasing blood volume

B. 

Increasing excretion

C. 

Increasing plaque buildup in arteries

D. 

Increasing heart rate

E. 

Epinephrine causing vasoconstriction

Increasing excretion

Which of the following structures has the lowest blood pressure?

A. 

Arterioles

B. 

Veins

C. 

Capillaries

D. 

Venules

E. 

Arteries

Veins

Which type of tissue classification does blood belong to?

A. 

Connective

B. 

Epithelial

C. 

Muscle

D. 

Nervous

E. 

Endocrine

Connective

All of the following are components of plasma in blood EXCEPT one. Which one is the EXCEPTION?

A. 

Antibodies

B. 

Hormones

C. 

Proteins

D. 

Platelets

E. 

Salts

Platelets

What are the glycoproteins found on the surface of a red blood cell that can trigger an immune response?

A. 

Myoglobin

B. 

Antibodies

C. 

Cholesterol

D. 

Antigens

E. 

Hemoglobin

Antigens

Which type of antibodies does an individual with type B blood produce?

A. 

Anti-A

B. 

Anti-B

C. 

Anti-O

D. 

Anti-A and Anti-B

E. 

No antibodies

Anti-A

Which of the following (donor → recipient) blood transfusions will result in agglutination?

A. 

Type O → Type AB

B. 

Type A → Type AB

C. 

Type B → B

D. 

Type AB → A

E. 

Type O → Type A

Type AB → A - Agglutination is a reaction where particles in a liquid clump together when antigens are surrounded by multiple antibodies. This reaction occurs when incompatible blood types are mixed, resulting in an immune reaction between the antibodies and antigens present.

A donor with type AB blood carries both A and B antigens. If the recipient has type A blood, they possess A antigens and produce anti-B antibodies. Therefore, if type AB blood is transfused into a recipient with Type A blood, agglutination will occur. This is because the recipient's anti-B antibodies will attack the B antigens present in the donor's AB blood.

Which of the following blood types can be safely transfused into an individual with type B- -blood?

A. 

B+

B. 

AB+

C. 

O-

D. 

O+

E. 

AB-

O- - An individual with type B- blood has type B antigens on their red blood cells but lacks Rh antigens, indicating they are Rh-negative. Therefore, they can accept blood from donors who are either B- or O-.

A father has type AB blood, and the mother has type O blood. What is the probability that their child will have type O blood?

A. 

0%

B. 

25%

C. 

50%

D. 

75%

E. 

100%

0%

All of the following are true statements about erythrocytes EXCEPT one. Which one is the EXCEPTION?

A. 

Have a biconcave shape to increase their surface area

B. 

Contains hemoglobin that transports oxygen throughout the body

C. 

Contains ribosomes to produce hemoglobin

D. 

The most abundant cell type in blood

E. 

Very flexible to fit through small vessels

Contains ribosomes to produce hemoglobin

Which of the following molecules is primarily responsible for buffering the pH range in the blood plasma?

A. 

Carbon dioxide

B. 

Hydrogen ions

C. 

Phosphate

D. 

Bicarbonate

E. 

Oxygen

Bicarbonate

Which of the following is the primary function of the enzyme carbonic anhydrase?

A. 

Lower blood pH by increasing proton release from hemoglobin

B. 

Trigger hemoglobin to release oxygen to specific tissues in need

C. 

Catalyze the reaction that regulates the intracellular phosphate buffering system

D. 

Directly neutralize the acidic compounds in the blood

E. 

Regulate pH balance by catalyzing the conversion of carbon dioxide and water into carbonic acid

Regulate pH balance by catalyzing the conversion of carbon dioxide and water into carbonic acid

Which type of junction does the blood-brain barrier consist of?

A. 

Tight junction

B. 

Gap junction

C. 

Synapse

D. 

Plasmodesmata

E. 

Desmosome

Tight junction

All of the following molecules could cross the semipermeable blood-brain barrier EXCEPT one. Which one is the EXCEPTION?

A. 

Oxygen

B. 

Albumin

C. 

Carbon dioxide

D. 

Cortisol

E. 

Vitamin D

Albumin - The blood-brain barrier allows water, some gasses, small lipid-soluble molecules (steroid hormones), and fat-soluble vitamins to pass.

When a blood vessel breaks, which of the following is first to the site of injury?

A. 

Clotting factors

B. 

Prothrombin

C. 

Fibrin

D. 

Thrombin

E. 

Platelets

Platelets

Which of the following best describes the positive feedback mechanism seen in blood clotting?

A. 

Breaks in blood vessels are eventually repaired to minimize blood loss

B. 

The formation of thrombin increases its own production by activating more clotting factors that convert prothrombin to thrombin

C. 

Fibrinogen is converted into fibrin, which in turn promotes further production of fibrinogen

D. 

Platelets, once activated, release substances that inhibit further platelet aggregation to control the clot size

The formation of thrombin increases its own production by activating more clotting factors that convert prothrombin to thrombin

Which enzyme catalyzes the conversion of fibrinogen into fibrin?

A. 

Platelets

B. 

Prothrombin

C. 

Thrombin

D. 

Fibrinase

E. 

Hemoglobin

Thrombin

How are leeches used in medical treatments?

A. 

Provide local anesthesia during minor surgeries

B. 

Increase the strength of fibrin

C. 

Prevent blood clots and improve blood circulation

D. 

Provide antibodies to an infection

E. 

Serve as a diagnostic tool for detecting blood clots

Prevent blood clots and improve blood circulation