Chapter 23 Flashcards
What is a food chain?
A simple linear diagram showing what eats what and the transfer of energy among trophic levels (too simplistic of a model)
What is a food web?
A more realistic model of energy transfer in ecosystems (complex -> depicts connections between different food chains)
What are primary producers?
Primary producers autotrophic, they produce their own energy rich organic compounds either photosynthetic or chemosynthetic.
What are consumers?
Primary consumers -> consume producers
Secondary consumers -> consume primary consumers
Tertiary consumers -> consume secondary consumers
What are keystone species?
Organisms that play a role in the population and the composition of species in an ecosystem, that is greater than expected (typically top predators, sometimes trophic level as well)
What is transfer efficiency and how can it vary?
Is the amount of energy that passes from one trophic level to the next
It varies between species, between stages of development, and according to environmental conditions
On average organisms have a transfer efficiency of about 10%
What is the microbial loop?
A side circuit of food chains in the marine environment, which is composed of microorganisms and return energy (that otherwise unavailable) back to the food chain
What are DOM and POM?
DOM (dissolved organic matter) is the result of normal metabolic activists of living organisms (E.G. sugar, amino acids, etc)
POM (particulate organic matter) sinks -> major source of energy for deep-sea organisms (e..g. fecal pellets, chitin, and cellulose structures, etc)
Why are DOM and POM important?
DOM are important because we think that this organic matter that is dissolved in the ocean of the worlds is one of the largest reserves, largest amount of organic carbon in the world. Which means represents a very large source of energy for other organisms, but only used by organisms that have a high surface/volume ratio
POM are important because the particles of organic matter that is sinking are an important source of energy for deep sea organisms,
What is DOM and POM origin?
DOM are present in the water, dissolved in the oceans of the world.
POM are present in the deep sea, they are sinking down the deep-sea
What is the surface to volume ratio?
Surface to volume to ratio.
Volume is the 3 Dmentional space inside the cell.
The greater the volume = more energy to stay alive and more waste to produce.
As the size of the cell increases the surface to volume ratio decreases.
How is the surface to volume ratio related to the ability of microbes to utilize DOM and POM?
Because the smaller the size of the cell the increase in surface to volume ratio which makes microbes more efficient to exchanging energy with the environment by utilizing DOM and POM so they can then return the waste to the environment BC they are smaller in size.
What are the main microbial groups involved in the microbial loop?
Bacteria
Bacteriophages (viruses)
Microflagellates and ciliates
What appears to be the role of viruses in the microbial loop?
Control bacteria population by infection and killing them.
How does energy flow between the main microbial groups and the food chains in the oceans?
Primary producers are eaten by primary consumers which are then eaten by secondary consumers which are eaten by keystone species; all of these produce DOM which is eaten by bacteria and bacteria is eaten by ciliates or microflagelltes which are eaten by primary consumers, all the primary produced and all the consumers then produce POM from waste which sinks the the deep sea and is eaten by bacteria or it can be dissolved into DOM.
