Flashcards
Importance of Biodiversity
Why is it important?
3 categories help maintain health of biosphere
Maintaining balance in terms of food, fresh water, organic materials for medicines, decomposition of wastes and sites for humans to enjoy natural beauty
Molecular (Genetic) Diversity
What is it?
Genes of a population, different alleles of a gene
Share similar structural and biochemical characteristics
Phenotypes (look like) of a species
Genetically distinct, reproductively isolated
Population (Species) Diversity
What is it?
Composed of some common elements, form trophic levels: producers (Plants), consumers (Humans/Animals), and decomposers (organisms that break down organic material)
Same species within area/group of individuals of one species in particular place and time
Classifications: Competition, predation, and symbiosis
Genetic drift - (Change in allele frequencies due to chance. E.g. eye colour)
What is it?
Random event
Survivors not more fit than others; survive through chance
Drastic reduction in gene pool, bottleneck (change in gene pool caused by drastic reduction in population size) may occur
Natural disaster e.g. fire survivors are there because fire didn’t get to them not because they were stronger
Founder effect e.g. organisms start new population on an island, do not necessarily represent original population they came from, random sample
The effects of genetic drift are the strongest in small populations
Competition and Predation
What is it?
Consumption of one population by another
Also drives adaptation, with prey attempting to avoid being eaten while predators develop more impressive ways to eat
Both predation and competition shape communities
Symbiosis
What is it?
Interaction between two different organisms through which one of them benefits
Other organism may also benefit, be harmed or even killed
Interactions that occur between two different species
Classified either mutualism, commensalism, or parasitism, depending on the impact the relationship has on both participants
Nutrition and Tropism
What is it?
Autotrophs make their own food. E.g. grasses, shrubs, trees
Heterotrophs take their energy from bodies of other organisms
Food Chains
What is it?
A simple sequence of who eats whom in an ecosystem
Shows what is eaten. E.g. the lettuce is eaten by the rabbit
Tropic Pyramids
What is it?
Feeding relationships
Trophic levels and are numbered, how far removed a predator is form the producer of the food web or chain
Producers are always the first trophic level, consumers are next
Energy
What is it?
Energy captured by plants, used by plants in its normal life processes
Not totally efficient, most of the energy is lost as heat
Some food may not have been digested
Some of the producers die before the consumer eats it
Second order consumers receive about 10% of the energy from the first order consumer
90% of the energy is lost at each trophic level of a food chain
Adaptations
What is it?
Advantage to an individual
Genetic, phenotypic - what it looks like
Structural, physiological (functional) or behavioural
Only give advantages in particular conditions, change, not still be advantageous
Adaptations Explained
Structural - morphology of a species
Physiological - metabolic (chemical) processes of a species
Behavioural - patterns of activity of a species
Ecosystem Diversity
What is it?
Different components, most ecosystems have their own particular community of producers, consumers, and decomposers
Majority of habitats are dry with nutrient poor soils and high light intensity
Produced adaptations in producers to cope with these conditions
Surviving The Elements
What is it?
Interactions in the community; intraspecific or interspecific, competition
Availability of resources; biotic or abiotic
Weather and climate
Human activities
Greater the molecular diversity in a population the more likely it will survive change in its habitat
Biodiversity and Biological Classification Questions
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