Ecology

Question 1

Ecology

Answer 1

Study of the interactions that determine the distribution and abundance of organisms. Considers interactions that occur both biotic and abiotic levels.

Question 2

Patterns of distribution

Answer 2

Random = equal probability of occurring anywhere. Regular = uniform spacing. Clumped = individuals live in areas of high local abundance separated by areas of low-abundance.

Question 3

biome

Answer 3

Major life zones. Terrestrial biomes are most often characterised by the main vegetation types. Aquatic biomes are described by their physical environment. Water is important in determining a biome.

Question 4

Factors that determine abundance and diversity of organisms

Answer 4

Availability of resources such as energy light temperature nutrients and water.

Question 5

Hopkins law

Answer 5

Air cools as it rises. Hot air can retain moisture.

Question 6

Coriolis effect

Answer 6

Patterns of deflection taken by objects.not firmly connected to the ground as they travel around the Earth. This deflection is based on earth's rotation and the different speeds and which the planet rotates depending on distance from the equator.

Question 7

Convection cell

Answer 7

Ascending warm moist air at equator releases rain. Descending dry cold air at 30 degrees North absorbs moisture but does not release it.

Question 8

Angle of incidence of sunlight

Answer 8

Sunlight strikes the tropics more directly. At higher-latitude sunlight strikes at an oblique angle and that is less effective in heating.

Question 9

Winds

Answer 9

Trade winds blow from east to west in tropics. Westerlies blow from West to East in the temperate zones.

Question 10

Rain shadow

Answer 10

Mountains obstructing prevailing winds force air to move up. Air cools it moves up and loses it's water content. Rainshadow forms on the other side with no rain falling in that area.

Question 11

Primary production

Answer 11

Conversion of energy into chemical energy that is stored in organic compounds in living organisms.
Chemotrophs = obtain the energy to oxidation of inorganic molecules
Phototrophs = use photosynthesis
Radiotrophs = fungi that hypothetically can use ionising radiation as an energy source.

Question 12

Net primary production

Answer 12

Gross production - cellular respiration.

Question 13

Trophic levels

Answer 13

The positions an organism occupies in the food chain. Primary producers = plants. Never more than 5 trophic levels because 90% of energy is lost as you move from level to level.

Question 14

Ecological efficiency

Answer 14

Percentage of energy from a food source that is used for growth and reproduction. Waste is the unassimilated energy. Growth is energy assimilated as biomass or reproduction.

Question 15

Bioaccumulation

Answer 15

Contaminant levels build up in an individual organism overtime

Question 16

Biomagnification

Answer 16

Contaminant builds up across food chain levels lowest in primary consumers and highest and quaternary consumers. Example is permafrost buildup of nuclear fallout, lichen and reindeer.

Question 17

Biodiversity

Answer 17

The variety or variability of life synonym eco system. Also measure a variation at the genetic species and ecosystem level

Question 18

Niche

Answer 18

What rules an organism fills in their habitat and where

Question 19

Realised niche

Answer 19

Actual distribution of the organism as limited by interactions with others

Question 20

Fundamental niche

Answer 20

Possible distribution of the organism as determined by its evolutionary history.

Question 21

Island equilibrium theory of biogeography

Answer 21

Species diversity on islands will represent a dynamic balance between the probability of successful colonisation by new immigrant species and Extinction of existing residents species.
Small islands have slower rates of immigration and higher rates of Extinction. Large islands have higher rates of immigration and slower rates of Extinction.

Question 22

Von Humboldt species-area curve

Answer 22

As the area explored increases species richness increases but to a certain point above which increased diversity would strain resources

Question 23

Specialists

Answer 23

More ecologically efficient but at the cost of having a more restricted fundamental niche when ample resources are available specialist outcompete generalists. Specialists are less resiliant to disturbance.

Question 24

Generalists

Answer 24

Less ecologically efficient but with a larger fundamental niche. More resilient in the face of disturbance.

Question 25

Competitive exclusion

Answer 25

A comparative advantage that will eventuate in success for the species and Extinction of the other

Question 26

Intermediate disturbance hypothesis

Answer 26

Diversity will be highest when disturbance prevents competitive exclusion but is low enough to allow for species to prosper. disturbance may be due to interaction with the environment or other species.

Question 27

Keystone species

Answer 27

Species with the largest number of interactions with an ecosystem. Had a disproportionate effect on other organisms. Examples include prairie dogs and sugar maple tree.

Question 28

Red Queen hypothesis

Answer 28

Evolutionary theory that species must constantly adapt evolve and proliferate in order to survive whilst competing against other ever-evolving species. Evolutionary arms race 4 survival. Example gazelles v cheetahs in terms of speed

Question 29

Symbiosis

Answer 29

Any relationship or interaction between two dissimilar organisms. includes parasitism, competition, predation and herbivory, mutualism commensalism and facilitation

Question 30

Biodiversity hotspots

Answer 30

Regions characterised by exceptional levels of plant endemism and excessive exceptionally rich in species. 34 on the planet.

Question 31

Population size parameters

Answer 31

Sources of increase = birth and immigration. sources of decrease = death and emigration

Question 32

Intrinsic rate of growth

Answer 32

Rate of growth with no extrinsic limiting factors. Constrained only by the species life-history traits. Leads to exponential growth curve.

Question 33

Exponential growth

Answer 33

Cause when there are unlimited resources and no external limitation. is not sustainable

Question 34

Logistic growth

Answer 34

Involves a carrying capacity. Population size increases until carrying capacity is reached at which point it will plateau or decrease. Carrying capacity is determined by interactions with the environment and other species.

Question 35

Life-history traits

Answer 35

Reflect evolutionary adaptations of reproduction strategies and age-specific distribution of reproduction and mortality. Traits include the number of offspring level of investment ages sexual maturity senescence and death

Question 36

Types of survivorship

Answer 36

Type 1 = mortality accelerates with age for example humans. Type 2 = mostly consistent mortality rate for example squirrels. Type 3 = mortality decelerates over lifespan but starts at high rate for example turtles.

Question 37

Precocial

Answer 37

Born in advanced state able to feed and move independently almost immediately

Question 38

Altricial

Answer 38

Born helpless requiring significant parental care to survive

Question 39

Iteroparity

Answer 39

An organism that's able to have offspring many times over the course of their lives

Question 40

Semelparity

Answer 40

Life history characterised by death after first reproduction for example major seed crops such as corn wheat and oats or salmon