Lecture #1

Question 1

What physical properties matter in marine environments?

Answer 1

temperature, salinity, viscosity, light, density, oxygen, pressure, heat capacity, currents

Question 2

Contrast marine and terrestrial environments

Answer 2

water has higher thermal capacity than air (so it heats up way slower than land does because it can absorb more heat)

water is denser and more viscous than air (makes it harder to cut through)

light is limiting as depth increases (disappears around 100 or so meters, so it is not widely available like it is on land)

water has low diffusion rates

less oxygen in marine environments

ocean currents move organisms around (planktonic organisms especially are at the mercy of currents)

Question 3

Endothermic

Answer 3

production and regulation of heat to maintain internal body temp

Question 4

Ectothermic

Answer 4

Tb = Te (body temperature = temperature of the environment)

Question 5

Density

Answer 5

how tightly a material is packed together, mass per unit volume

water is 800x denser than air, so it provides considerable support to organisms to move up and down water column

Question 6

Viscosity

Answer 6

how thick material is and how easy it is to move through it; water is quite viscous, so smaller organisms like plankton have a much more difficult time moving than organisms like a mako shark or tuna

Question 7

Light Attenuation

Answer 7

light decreases with depth, which is why photosynthetic organisms must live at or near the surface, or be able to travel to areas with sufficient light levels

Question 8

Oxygen and Diffusion

Answer 8

water has lower concentration of oxygen and much slower rate of diffusion (respiration harder in water)

Question 9

Currents

Answer 9

more impactful than winds; dictates where planktonic species end up