Topic 4.1 Flashcards
Pre-reproductive barriers
Geographic: physical distance
Ecological: different environments (tree, grass)
Temporal: e.g. weather
Behavioural: e.g. mating calls
Mechanical: physically cannot mate
Gametic: gametes are not compatible
Post-reproductive barriers
Infertile offspring
Unviable zygote
mixotrophs
(Definition)
Use combination of different modes of nutrition
Examples of mixotrophs
Algae: euglena sp.
- will photosynthesize in sufficient light
- can ingest food particles by phagocytosis
Venus flytrap (Dionaea muxipula)
- can photosynthesize
- traps and digests insects and spiders (to compensate for nutrient poor soil of subtropical wetlands)
Population
Group of organisms of the same species in the same area at the same time
Types of heterotrophs
- consumers
- herbivores
- omnivores
- carnivores
- scavenger
Consumer
- Feed on anything alive or dead
- can be unicellular or multicellular:
Uni: ingest via endocytosis, digest in vacuole
Multi: ingest via mouth, digest in digestive system
Categorized by tropic groups: primary, secondary, etc.
Herbivore
Consumes producers
Omnivore
Consumes both producers and consumers
Carnivores
Feed on other consumers
Scavengers
Feed on mostly dead + decaying animals
Detritivores
Obtain organic nutrients from feeding on non-living organic sources such as detritus and humus
Humus: decaying leaf litter mixed w/ soil
Detritus: dead, particulate organic matter (decaying matter and fecal matter)
Saprotrophs
Live on non-living organic matter. Secrete digestive enzymes on to organic matter and absorb nutrients of digestion
(Also known as decomposers)
Positive association
Species found in same habitat
Negative association
Species occur separately in differing habitats, are in competition and cannot be in the same area
