1b. Basics In Ecology And Biology

Question 1

Hierarchies of life

Answer 1

Taxonomic
Ecological
Tropic

Question 2

Taxonomic

Answer 2

Classification and naming of organisms. Common names not always clear

Scientific name = Latin. Genus = generic and species = specific name. Family, species and genus are the most important names.

Question 3

Clade

Answer 3

Lineage of different related species that arise from a common ancestor species

Question 4

Speciation

Answer 4

The development of two or more genetically differential species from a single common ancestor species

Question 5

Evolution

Answer 5

Genetically controlled changes in physiology, anatomy and behaviour that occur to Claude over time. Does not always lead to new species. Evolution doesn’t always lead to new species

Question 6

Allopathic speciation

Answer 6

Formulation of new species by geographic isolation=

• natural selection for beneficial traits in each environment
• isolation of populations can increase speciation

Question 7

Sympatric speciation

Answer 7

Formation of species where genetic change causes species to become reproductively isolated in the same geographic area.

This can be caused by polyploid (mutations), more common in plants

Question 8

Ecological hierarchy - individual

Answer 8

Individual organism

Question 9

Population

Answer 9

All individuals of a given species in a prescribed area, able to interbreed frequently.

Question 10

Metapopulations

Answer 10

Separated populations, able to interbreed extremely infrequently

Question 11

Community

Answer 11

All populations of all species in a prescribed area

Question 12

Ecosystem

Answer 12

All interacting physical and biological components of a prescribed area

Question 13

Biome

Answer 13

Large area of the earths surface that have similar climate and vegetation

Question 14

Biosphere

Answer 14

Life on Earth

Question 15

Tropic hierarchy

Answer 15

Organisation of life over the food chain = transfer of energy trophy

Question 16

Autotrophs

Answer 16

Can fix carbon, usually through photosynthesis

Question 17

Heterotrophs

Answer 17

Cannot fix carbon and need to take up organic carbon

Question 18

Photosynthesis by autotrophs = 3 pathways have evolved to overcome limitations due to H2O loss:

Answer 18

1. C3 pathways
2. C4 pathways
3. CAM ( crissulacean acid metabolism) pathway

Question 19

C3 pathway

Answer 19

Co2 converted in 3-carbon molecule, 95% of all plants adapted to temperatures of 20-30 degrees

Question 20

C4 pathway

Answer 20

CO2 converted in 4 - carbon molecule. Higher efficiency of CO2 uptake, optimal for warm and dry climates

Question 21

CAM

Answer 21

CO2 assimilation during the night, adaptations to arid conditions.

Question 22

Omnivores

Answer 22

Eat animals and feed at more that one tropic level

Question 23

Gross primary productivity

Answer 23

Fixation of energy by photosynthesis

Question 24

Liebigs law

Answer 24

Nutrient lo,toed yields are dictated by the availability of most limiting nutrients. This is very important info for farmers

Question 25

Nitrogen

Answer 25

78% of the atmosphere

Taken in by plants by ammonium or nitrate. Nitrate is made available through nitrifying bacteria in the soil. Plants preference for nitrogen differs between ecosystems and can depend on climatic conditions

Nitrogen fixers in soil = bacteria

Plants who can’t take in nitrogen which has led to meat eating plants like Venus fly traps

Question 26

Net primary productivity

Answer 26

GPP Minus plant respiration = plant biomas change over time

Question 27

Flow over energy through a web

Answer 27

On average 10% of renege is passed to the next level

Mammals only assimilate 3% of energy. Insects assimilate 40%

A lot of plants and insects only support a few consumers

Question 28

Carrying capacity

Answer 28

Maximum population size given the available resources

Question 29

Plant nutrients

Answer 29

Plants require many elements for growth and metabolism

• Marco elements participate in metabolism.
• Trace elements, often heavy metals, required for enzyme reactions
• Facultative elements only required in some plant groups

Availability of nutrients depend on the geology, climate, vegetation and human influence

Question 30

Plants - too low pH release

Answer 30

Too much iron and aluminium which may be toxic. Reduce soil biota and break down of plant

Question 31

Plants - too high pH

Answer 31

May limit nutrient availability. Optimal is a neutral pH

Question 32

Global biogeochemical cycles

Answer 32

1. nitrogen
2. Phosphorus
3. Carbon