WSU Bio 106 Exam 4 Test Questions
and All Correct Answers 2025.
What is the difference between blood and hemolymph - Answer Blood is contained to vessels
and is distinct from interstitial fluid whereas hemolymph acts as both blood and interstitial fluid
What are the major types of blood vessels - Answer Arteries: carry blood from the heart to
organs throughout the body
Capillaries: microscopic vessels with very thin, porous walls
Veins: the vessels that carry blood back to the heart
What adaptations allow an animal to use diffusion across its skin as the only mechanism for gas
exchange - Answer Flat shaped body: adaptation to increase surface area relative to volume
What is the relationship between the surface area-to-volume ratio and efficiency of exchange
across a surface - Answer Surface are must be large enough to allow O2/CO2 exchange for
entire body
The higher the surface area and the lower the volume, the greater rate of diffusion
Not all animals use a circulatory system to transport oxygen and remove carbon dioxide. How
do insects and some spiders accomplish gas exchange - Answer Tracheal system, gas exchange
not tied to hemolymph or blood
Structure: Spiracles- let air into tube system, Trachea- tubes leading from spiracle to tissue
In a two-chambered heart, where does the blood go after it leaves the atrium? (Give the entire
pathway ending back in the atrium). What happens as it passes through the capillary beds in the
tissues and gills - Answer To the ventricle towards capillary bed
(ventricle--->Gills ---> Body Capallaries---> Veins---> Atrium)
, atrium- left ventricle- artery to body tissues- capillary beds in body tissues (delivers load of O2
picks up CO2 waste)- vein back to heart- right atrium
Pulmonary: heart- lungs- heart
Systemic: heart- body- heart
Which parts of the pathways you outlined above carry oxygenated blood? Which carry de-
oxygenated blood - Answer Oxygenated: left side
(Lungs, Left Atrium, Left Ventricle, Capillary beds, Aorta)
Deoxygenated: right side (Right Atrium, Right Ventricle, Pulmonary Artery)
What is "transposition of the great vessels" and how does it affect blood circulation - Answer
Transposition of the great vessels is a condition that babies can be born with which causes the
arteries leaving the left and right ventricles to be switched. This affects blood circulation in that
there is no cross over, so the oxygenated blood from the lungs never makes it through the rest
of the body
What is counter-current exchange - Answer the exchange of a substance or heat between two
fluids flowing in opposite directions (gases flow down concentration gradient from higher
partial pressure to lower, water has higher PO2 than blood as it approaches gills)
What is counter-current flow - Answer between water and blood vessels increase ability to
extract maximum O2 from water into blood (between water and blood vessels in each filament,
water and blood are flowing in two different directions)
Contrast it with co-current exchange - Answer IF flow is co-current (parallel) blood reaches
equilibrium with water. 50% saturation is best you can do. But if flow is counter current: transfer
more O2 into blood that is why it is more efficient (animals use counter-current flow)
How does counter-current flow allow blood to pick up more oxygen than co-current flow would
(Know that animals use counter-current flow and not co-current flow) - Answer Because co-
current reaches equilibrium so it can't pick up anymore and counter current flow picks up more
because they are flowing opposite of each other. Blood becomes more saturated as it moves
opposite the water, but meets with fresher water the further it moves, allowing it to continue to
gain oxygen
and All Correct Answers 2025.
What is the difference between blood and hemolymph - Answer Blood is contained to vessels
and is distinct from interstitial fluid whereas hemolymph acts as both blood and interstitial fluid
What are the major types of blood vessels - Answer Arteries: carry blood from the heart to
organs throughout the body
Capillaries: microscopic vessels with very thin, porous walls
Veins: the vessels that carry blood back to the heart
What adaptations allow an animal to use diffusion across its skin as the only mechanism for gas
exchange - Answer Flat shaped body: adaptation to increase surface area relative to volume
What is the relationship between the surface area-to-volume ratio and efficiency of exchange
across a surface - Answer Surface are must be large enough to allow O2/CO2 exchange for
entire body
The higher the surface area and the lower the volume, the greater rate of diffusion
Not all animals use a circulatory system to transport oxygen and remove carbon dioxide. How
do insects and some spiders accomplish gas exchange - Answer Tracheal system, gas exchange
not tied to hemolymph or blood
Structure: Spiracles- let air into tube system, Trachea- tubes leading from spiracle to tissue
In a two-chambered heart, where does the blood go after it leaves the atrium? (Give the entire
pathway ending back in the atrium). What happens as it passes through the capillary beds in the
tissues and gills - Answer To the ventricle towards capillary bed
(ventricle--->Gills ---> Body Capallaries---> Veins---> Atrium)
, atrium- left ventricle- artery to body tissues- capillary beds in body tissues (delivers load of O2
picks up CO2 waste)- vein back to heart- right atrium
Pulmonary: heart- lungs- heart
Systemic: heart- body- heart
Which parts of the pathways you outlined above carry oxygenated blood? Which carry de-
oxygenated blood - Answer Oxygenated: left side
(Lungs, Left Atrium, Left Ventricle, Capillary beds, Aorta)
Deoxygenated: right side (Right Atrium, Right Ventricle, Pulmonary Artery)
What is "transposition of the great vessels" and how does it affect blood circulation - Answer
Transposition of the great vessels is a condition that babies can be born with which causes the
arteries leaving the left and right ventricles to be switched. This affects blood circulation in that
there is no cross over, so the oxygenated blood from the lungs never makes it through the rest
of the body
What is counter-current exchange - Answer the exchange of a substance or heat between two
fluids flowing in opposite directions (gases flow down concentration gradient from higher
partial pressure to lower, water has higher PO2 than blood as it approaches gills)
What is counter-current flow - Answer between water and blood vessels increase ability to
extract maximum O2 from water into blood (between water and blood vessels in each filament,
water and blood are flowing in two different directions)
Contrast it with co-current exchange - Answer IF flow is co-current (parallel) blood reaches
equilibrium with water. 50% saturation is best you can do. But if flow is counter current: transfer
more O2 into blood that is why it is more efficient (animals use counter-current flow)
How does counter-current flow allow blood to pick up more oxygen than co-current flow would
(Know that animals use counter-current flow and not co-current flow) - Answer Because co-
current reaches equilibrium so it can't pick up anymore and counter current flow picks up more
because they are flowing opposite of each other. Blood becomes more saturated as it moves
opposite the water, but meets with fresher water the further it moves, allowing it to continue to
gain oxygen
