PSEC Year 1 Flashcards
Name 2 Abiotic factors in Ecology
Any two from:
-Temp -Soils
-Relative humidity
-pH -Topography
-Salinity -Altitude
-Pollutants -Latitude
-Climate -Nutrient availability
-Geology -Stochastic events
Name two levels of organisation in ecology
Any two from:
Biosphere
Biome
Ecosystem
Community
Population
Organism
Name 3 Biotic Factors that could influence an ecosystem
Any 3 from:
Competition
Predation
Herbivory
Pollination
Seed Dispersal
Reproduction
Care of offspring
Social Interactions
Paracitism
Disease
Mutualism (symbiosis)
Defences
Define the term ‘Niche’ in terms of ecology
The role and position a species has in its environment
What is an autotroph
An organism that is able to use external sources of energy (e.g sunlight) in the synthesis of their organic food materials.
What are photosynthetic organisms and give an example.
Autotrophs that have special pigments that capture and convert light into usable chemical energy
e.g Algae, plants and certain prokaryotes
What is Heterotrophic nutrition and name the four different types
Heterotrophic organisms must be supplied with ready made organic compounds from which they derive their energy
holozoic
saprotrophic
parasitic
mutualism
Define holozoic nutrition
Complex food taken into specialised digestive system – characteristic of free-living animals
Define Saprotrophic nutrition
Where an organism feeds on dead organic remains of other organisms
What is parasitic nutrition
Where an organism obtains food from another living organism, called a host
What is Mutualism
A form of symbiosis – Two organisms where both organisms derive a benefit from the relationship
Put these 5 stages of Holozoic nutrition in order:
Digestion
Assimilation
Egestion
Ingestion
Absorption
Ingestion
Digestion
Absorption
Assimilation
Egestion
Define ingestion
Food taken into the body through the mouth
Define the term digestion
Food broken down by enzymes in the stomach, duodenum and ileum
Define the term absorption in terms of ecology
Smaller molecules taken into the bloodstream through duodenum and ileum
Define the term Assimilation
absorbed products are incorporated and used by the organism
Define Egestion
The undigested parts of food are dispensed through defaecation
What is another name for saprotrphic organisms and give two examples
Decomosers
Fungi and bacteria
what are parasites that live on the outside of the hosts body called
Ectoparasites
What are parasites that live inside the host called
Endoparasites
what % of energy is carried over between trophic levels
10%
what % of energy is lost through respiration between trophic levels
90%
what is gross primary productivity (GPP)
All the biomass generated by primary producers
What is Net Primary Productivity (NPP)
What is left over after the primary producers have used the energy for respiration
What does the 10% rule limit
The number oftrophic levelsanecosystemcan support.
What is Parasitism
is a relationship where one organism benefits whilst reducing the fitness of another.
What is parasitoidism
is a relationship where one organism benefits and the other organism dies (not necessarily immediately !)
What is commensalism
a relationship between two organisms where one organism benefits and the other is not negatively affected.
what is a predator prey relationship?
a feeding relationship between two organisms (hunter and hunted).
List 4 predator attributes
Any four from:
Teamwork
Camouflage
Patience/ immobility
Trapping
Strength
Lures/ deception
Stamina
Venom/poison
Sonar/Electromagnetism
Use of tools/ weaponry
Stealth
Speed
Define the term population
all the individuals of a species that live together in an area
What are the three key measures of population
Size
Density
Dispersion
define fecundity
The Biological potential to have offspring dictated by the number of gametes
define fertility
the actual rate of reproduction and births (Measurable)
What are the three types of dispersion
clumped
even or uniform
random
what are limiting factors and name two
Any biotic or abiotic factor that restricts the existence of organisms in a specific environment.
Amount of Food
Amount of Water
Temperature
Amount of Suitable Habitat
Available Light
Define density dependent factors
Factors that can affect a population that increase as the population density increases.
name 2 density dependent factors
Disease
Parasitism
Prey Availability
Predation
Competition
Define density independent factors
factors that control a population irrespective of population density
List 2 density independent factors
Light
Nutrients
Climate
Seasonality
Natural Disasters
what is a carrying capacity?
the maximum population size that can be supported by the available resources
List three qualities of r strategists
Short life span
Small body size
Reproduce quickly
Have many young
Little parental care
give an example of an r strategist
Cockroaches, Weeds, Bacteria, House Flies
what kind of environments do r strategists live in
unstable
what kind of environment do K strategists live in?
Stable
List three qualities of K strategists
long life span
large body size
reproduce slowly
have few young
provides parental care
Give an example of a k strategist
humans, elephants
What is a type I survivorship curve
organisms that have low mortality until late in life when aging takes its toll.
Give an example of an organism with a type I survivorship curve
humans
What is a type II survivorship curve
the chance of death is equal at all ages or those that suffer severe random mortality throughout life
Give an example of a type II survivorship curve
Many songbirds
What is a type III survivorship curve
very high mortality among the young but flattens out as those individuals who reach maturity survive for a relatively longer time
Give an example of an organism with a type III survivorship curve
Small Mammals and Fish
(many r strategists)
What are the 3 forms of competition
Interference Competition
Exploitation Competition
Apparent Competition
what is a boom population cycle
Small population well below carrying capacity
Absence / low population of a predator / competitor
High Fecundity
Low Infant Mortality
High Food Availability
High quality, available habitat
What is a bust population cycle
Population outstripping the carrying capacity – The environment is no longer able to support the large population
Increased intra-specific competition
Decreased food availability
Reduced fecundity
Reduction in habitat
Increased mortality (often severe)
What is taxonomy
The classification and naming of living organisms in an ordered system
What are the five kingdoms
Animalia
Plantae
Fungi
Protoctista
Monera
what is the genetic make up of of an organism called
A Genotype
Define the term ‘Divergent evolution’
Divergence from a common ancestor. One species becomes many to fill the available niches
give an example of divergent evolution
Darwins finched
Define parallel evolution
organisms not closely related evolve similar adaptations as they live in similar environments or ecological niches
e.g Hedgehog/Echidna/Tenrec/Porcupine
Define convergent evolution
Very distantly related organisms evolve similar traits (analogous structures) as a result of having a similar lifestyle.
e.g Birds (Aves), Mammals (Mammalia) and Reptiles (Reptilia) independently evolved the wing
What is the difference between parallel and convergent evolution
convergent evolution occurs when descendants resemble each other more than their ancestors did with respect to some feature. Parallel evolution implies that two or more lineages have changed in similar ways, so that the evolved descendants are as similar to each other as their ancestors were
What is Co-evolution
one species acts as a selective force on a second species, inducing adaptations that in turn act as selective force on the first species.
What did Mendel figure out
he basic principles of genetics.
He showed that offspring
received characteristics from both
parents, but only the dominant characteristic trait was expressed.
What was darwins theory
Where food was limited, competition meant that only
the fittest would survive.
This would lead to the natural selection of the best adapted individuals and eventually the evolution of a new species.
What was Alfred Russell-Wallace’s theory?
species evolve by adapting to their environment
Name 3 reasons for global ecosystem change
any three from:
Over harvesting
Introduction of non native species
Habitat destruction
Fragmentation
Climate change
Any form of pollution