IB BIOLOGY B4.2 Ecological Niches

Habitat abiotic factors

made up of non-living factors

Habitat biotic factors

other living organisms

Niche

a unique role that a species plays in its community, including habitat and activities

Obligate anaerobes

poisoned by oxygen (e.g. lives in soil, deep water, animal intestines) (the og prokaryotes)

obligate aerobes

require oxygen

What's hypoxia?

the reduction of O2 (oxygen)

What's anoxia?

The absence of O2 (oxygen)

Facultative anaerobes

Capable of anaerobic and aerobic respiration

Fundamental niche:

Fundamental niche: the potential of a species based on adaptations and tolerance limits.

Realized niche

Realized niche: actual extent of a species when in competition with another species

Autotrophs

Make their own food from inorganic substances

Heterotrophs

Must eat or absorb other organisms or their by-products for nutrition.

Holozoic nutrition

Ingestion, internal digestion, absorption, assimilation, and egestion.

Mixotroph

can make their own food or ingest another organism for it.

Competitive exclusion principle

No two species in a community can occupy the same niche (one will die out and give way for other or both population numbers will decrease).

Saprotrophic nutrition

Decomposers. Secrete digestive enzymes and absorb the products of digestion

Archaea

One of the three domains of life. Obtain energy for ATP production through: 1) Photosynthesis, 2) chemosynthesis, 3) Heterotrophic nutrition.

Chemoautotroph

Energy created using chemical reactions and not the sun - chemosynthesis

Incisors are for

cutting off bite-sized pieces of food

Canines are for

ripping meat and tougher foods. Are sharper

Premolars

For crushing up/slicing food

Molars are for

grinding food