18 April - Circulatory systems

Question 1

Na+

Answer 1

Wants to be inside the cell because

• Concentration gradient
• Charge gradient

But it can’t because

• impermeability of cell membrane
• Na+/K+ pump

Question 2

Aerobic catabolism

Answer 2

produces ATP needed for action potentials and muscle contractions
Happens either by glycolysis or Kreb’s cycle
O2 required to convert NADH2 and FADH2 to something useable

Question 3

Carbon Cycle

Answer 3

Combustion and metabolism

Fuel + O2 = CO2+H2O + energy (heat)

Question 4

Oxygen flow

Answer 4

Governed by Fick’s law
-Diffusion rate as a function of pressure differential, surface are, diffusivty and diffusion length

Governed by Flow rate

• Rate = DeltaP/R
• function of viscosity, tube length, tube radius r, resistance R
• R=1/r^4

Convective transport rate

• Rate= C x F
• concentration and flow rate

Smaller vessels = less flow
Smaller tubes = more resistance
Moving air or fluid increases diffusion rate

Respiration= obtaining O2
Circulation = delivering O2

Question 5

Types of circulation

Answer 5

None
Open
Closed

Question 6

No circulatory system

Answer 6

Sponges = incurrent and excurrent pores
Hydra = gastrovascular cavity
Nematodes=circulation mixed with digestive tract
Small creatures don’t need a large circulatory system

Question 7

Open circulatory system

Answer 7

No distinction between blood and body fluids
Hemolymph: mix of blood and bodily fluid
Separate from respiratory system
Low water pressure 
Low efficiency
No direction to tissues that need more
Arthropods and mollusks

Question 8

Closed circulatory system

Answer 8

Blood enclosed in blood vessels
Transported through body
Pumped by heart
Echinoderms and chordates

Question 9

Vertebrate circulatory systems

Answer 9

Chambered heart with single loop

• two pumping chambers
• circulatory integrated with respiratory system
• Low blood pressure
• limited O2 delivery
• solution is countercurrent system: water flows in opposite direction of blood