midterm 2 marine science

Eutrophication

build up of organic matter in aquatic systems (harmful algal blooms)

define harmful algal bloom

large blooms of toxin-producing phytoplankton that negatively impact marine or human populations

What causes eutrophication?

usually a result of nutrient enrichment, may be natural or often anthropogenic. Nitrogen pollution and dead zones.

What is the paradox of the plankton? Why are plankton able to thrive?

The paradox of the plankton notes that although there are many plankton species live in the same area and compete for the same few resources (like light and nutrients), they still manage to survive together

This is because plankton have a variety of temperature, light, salinity, and nutrient requirements

what are the sources of nutrients in different areas of the ocean

Nutrient cycling, Phytoplankton blooms, Pycnoclines (thermo- and halo-), nutrient mixing

what are phytoplankton?

tiny plant-like organisms that float in the ocean and make their own food using sunlight. They are the base of the marine food web and produce most of earth’s oxygen.

diatoms

have glass-like shells made of silica and live in colder, nutrient-rich waters.

dinoflagellates

have two little tails (flagella) that help them move. some can glow in the dark (bioluminescent), and some cause red tides

coccolithophores

covered in tiny calcium plates that look like shields. they make big white blooms in the ocean that can even be seen from space

cyanobacteria

blue-green algae. tiny bacteria that also photosynthesize. they’re super old and helped make oxygen in earth’s early atmosphere.

virioplankton

viruses

bacterioplankton

bacteria; free living planktobacteris and epibacteria attached to larger particles

mycoplankton

fungi

Ichthyoplankton

planktonic fish (generally, eggs and larval stages)

Phytoplankton

photosynthetic microalgae, cyanobacteria, and prochlorophytes

zooplankton

free floating animal whose movements are largely determined by water movements

holoplankton

organisms that spend their entire lives in the plankton

meroplankton

organisms that spend only part of their lives in the plankton. ex. larval stages of fish

what is the role of zooplankton in food webs

zooplankton consume phytoplankton, which consume nutrients in the ocean

What is diel vertical migration by zooplankton

daily movement of zooplankton and other small organisms through water column.

night: zooplankton rise toward the ocean surface where light levels are low but food/phytoplankton is abundant

day: zooplankton go deeper, darker and colder water to avoid predators

what are nekton?

animals with sufficient swimming abilities to overcome effects of ocean currents

Gonochronistic

seperate sexes. never change

protogyny

sex change from female to male

protandry

sex change from male to female

oviparous

lay eggs. Producing young by means of eggs that are hatched after they have been laid by the parent.

pelagic

into the water column. Releasing eggs are giving birth in the open water column.

demersal

on the sea floor or other substrate. Strategy were fish deposit eggs on or near the sea floor.

ovoviparous

Eggs laid into oviduct, where they develop results in live birth.

viviparous

gestate young with placenta and give live birth.

bradycardia

slowing heart rate (diving reflex)

peripheral vasoconstriction

shunting blood from extremities to the core of the body (diving reflex)

counter current heat exchange

when warm and cold blood flow in opposite directions next to each other, allowing heat transfer between them.

blood vessels carrying warm blood from the body’s core run right next to vessels carrying cold blood coming from the skin or extremities. the warm blood warms the cold blood before it goes back to the body’s core

what is osmosis?

movement of H2O [H2O → solute]

what is rugosity?

a measure of small-scale variation in the height of a surface. The “bumpiness” that breaks up the laminar flow.