Chapter 15 (Micro Iii)

Front 1

ecosystem

Back 1

interaction between living organisms and abiotic elements such as minerals, gasses and water

Front 2

community

Back 2

all living organisms in an ecosystem make up the community

Front 3

individual cells

Back 3

what makes up communities

Front 4

population

Back 4

groups of individual yet similar cells are populations

Front 5

primary producers

Back 5

organisms that harness light energy through photosynthesis or chemosythesis to generate energy.

in the process fix inorganic carbon to inorganic molecules

Front 6

consumers

Back 6

not capable of harnessing light energy

ingest primary producers and use the organic molecules produce to generate eneryg.

Front 7

Deocmposers

Back 7

break down dead organic matter and recycle the constituent parts back into the environment.

Front 8

basic physiological activities are important to consider

Back 8

metabolic activities it undergoes based on available resources.
ability to adapt in the environment
activities required to produce organic matter, decompose, and recycle

Front 9

what is biofilms

Back 9

an accumulation of microorganisms on solid surfaces to form stable, structured communities of microbes supported by an extracellular polysaccharide matrix.

Front 10

where can biofilms be found

Back 10

on surfaces that are capable of picking up nutrients and exposed to microbes

rocks in streams, plaque on teeth, and shower drains.

Front 11

how does SSU rRNA gene sequences assist as a phylogenetic tool

Back 11

have regions that are highly conserved and regions that are highly variable

variable regions can be used as identifiers of phylogenetic relationships between organisms.
- their phylogeny is indicative to how closely they are related evolutionary.

Front 12

what is an OTU

Back 12

OTU is an operation taxonomic unit
it is a method of classification designed to group microbes based on the similarity of their SSU rRNA gene sequences.

- grouped if >97% sequence similarity

Front 13

what gave rise to OTUs

Back 13

OTUs arose because of the difficulty in grouping them into species

they do not sexually reproduce.

Front 14

is is the stable isotope probe method used in studying microbial metabolism

Back 14

SIP is useful to determine metabolism that can't be cultured.
if they are capable of metabolizing the nutrient, the radioisotope will be incorporated into their DNA or RNA and this can be detected by analyzing the DNA or RNA after adding the nutrient.

Front 15

what is oligotrophy

Back 15

the use of nutrients at very low concentrations.

typically occurs in ecosystems or niches where nutrients are present in minor amounts.

Front 16

conditions found in the three main zones of the ocean

Back 16

First 200 m is referred to as the surface zone of the ocean (light can penetrate through water)

Dark mid-water zone does not receive light; temp:2-3C

Deep sea zone: extends below 4000 m and has very high pressure.

Front 17

what are phytoplankton

Back 17

photosynthetic microbes that live int he surface zones of oceans.

Front 18

role of phytoplankton

Back 18

contributes to the oxygen levels in the ocean.

capable of fixing nitrogen gas which contributes the the availability of nitrogen in the ocean.

Front 19

what are zooplankton and viruses in surface ocean waters

Back 19

non-photosynthetic eukaryal microbes that graze on photoplankton in the surface zone.
viruses cause death of phytoplankton by infecting them.

Front 20

roles of zooplankton and viruses in surface ocean waters

Back 20

grazing of both on photoplankton result in the release of nutrients by the photoplankton thus distributing the carbon and energy throughout the ocean ecosystem

Front 21

layers associated with microbial life found in freshwater ecosystems

Back 21

Upper layer: warmer, low density water; aerobic conditions that allow photosynthesis
Middle Layer: thin variable layer call Thermocine - temperature and density is rapidly changing; layer is aerobic; contains heterotrophs that consume the primary producers in the upper layer.
Lower Layer: Colder, high-density water; anoxic; contains methane oxidizing and nitrate reducing bacteria.

Front 22

how do soils form

Back 22

from the microbial decomposition of dead plants and animals and the weather of rocks that contribute minerals.

nutrients are supplied from the roots of plants which helps expand the microbial communities in soils

Front 23

What are the three layers soil is divided into

Back 23

A, B, and C soil horizons

Front 24

distinguish between A, B, and C soil horizons

Back 24

Deepest layer: C horizon is close to the bedrock and is mostly inorganic matter.
Subsoil: B horizon is above C and contains organic matter
Topsoil: A horizon has the most organic matter due to nutrients supplied by the roots of plants and decomposing biomass.

Front 25

rhizosphere vs. bulk soil

Back 25

is the layer of soil directly surrounding the roots of plants.

contains much more organic carbon than bulk soil; thus, greater number of microorganisms growing in these areas comparatively.

Front 26

how in lignocellulose degraded in the environment

Back 26

can't be broken down by microorganisms.

certain fungi contain enzymes like cellulases and peroxidases which depolymerize lignocelluloses into sugars and aromatics.

absence of fungi, lingnocellulose will eventually breakdown but a lot more slowly.

Front 27

humic substances

why are the important in soil ecology?

Back 27

humic substances are organic molecules present in teh soil from the partial degradation of complex like lignin.

they help soil aggregate and form a heterogenous mixture; allows diverse microenvironments to arise, which contributes to the wide diversity of soil habitats.

Front 28

what are the environmental conditions present in hydrothermal vents?

how are these vents formed?

Back 28

regions near volcanoes where molten rock interacts with seawater to cause a violent release of CO2, methane, and hydrogen sulfide.

vents forms due to plate movements and volcanic activity, which allows minerals to be released.