IB Biology B4.1: Adaptations to environment

Habitat

The natural home or environment of an organism.

Species

A group of organisms that can interbreed and produce fertile offspring.

Population

A group of individuals of the same species living in a specific area.

Community

A group of different species that live together in one area.

Ecosystem

A biological community of interacting organisms and their physical environment.

Biotic

Relating to or resulting from living things, especially in their ecological relations.

Abiotic

Physical rather than biological; not derived from living organisms.

Xerophyte

A plant adapted to survive in an environment with little water.

Prop Roots

Roots that grow above the ground to provide support.

Aerial Roots

Roots that are exposed to the air and help in climbing.

Optimum Range

The range of environmental conditions that is most favorable for a species.

Zone of Stress

The area where environmental conditions are less than optimal for a species.

Zone of Intolerance

The area where environmental conditions are too extreme for a species to survive.

Types of transect line sampling:

• continous line: every species touching tape measure

• interuppted line: species touching line at intervals

• continous belt: qudrats places end-toend- along line

• interuppted belt: qudrats placed at intervals

Mutualism

A symbiotic relationship where both species benefit.

Coral Reef formation

• symbiotic relationship between xooxanthellae and coral polyps

• Polyps provide shelter

• polyps respire →CO2 →used by xooxanthellae in photosynthesis →O2 released

Factors envolved in coral reef formation

• water depth: ↓ light ↓ photosynthesis

• pH: ↓ pH = outer calcium layer on polyps dissolves

• Salinity: osmotic potential

• Temp: Coral bleaching

• Water clarity: ↓ light

Biome

a large community of plants and animals that has occurred as a result of environmental factors (temp + rainfall)

• many ecosystems

• similar communities →similar selection pressures →similar morphology

Climograph

A graphical representation of the relationship between temperature and precipitation over a specific period.

Desert

↓ rain ↑ temp (day) ↓ temp (night)

• sparse vegetation (spines) + burrowing nocturnal animals

Grasslands

• semi arid (20-30º)

• ↑ grass

• ↑ grazers ↓ predators

Tundra

• ↓ rain (-40-18º)

• no trees + dark periods

• animals migrate when harsh

Taiga

• ↑ snow (-40-20º)

• coniferous trees

• adapted animals

Tropical rainforest

• ↑ rain (20-25º)

• ↑ biodiversity

• nutrient-poor soil ( rain overland flow)

Temperate forest

• ↑ rain: 4 moderate seasons

• rich soil

• ↑ biodiversity

• deciduous trees

Sand Dune grass species

Marram Grass in:

• ↓ water

• ↑ salinity

• ↓ nutrients

is a Xerophyte

• thicky waxy cuticle (↓ evaporation)

• rolled leaves + hairs trap water vapour

• sunken stomata traps water in pits

Challenges:

• dry air →steep coc. grad →evaporation

• ↓ soil →lost water not replaced

Tropical Tree species

Mangrove trees in:

• ↑ salinity

• ↓ fresh water

• ↓ oxygen

Red Mangroves	Black Mangroves
Ariel root systems: parts of root above water to take in oxygen propped up roots → stability in soft soil partially underwater →shelter for marine animals	Pneuomatophores grow verticallly upwards our of th water logged soil have cells that filter out sand and prevent outwards movement of water

Challenges:

• cells in underwater roots cant take oxygen and rspire

• ↓freshwater so osmotic potential

Hot desert adaptations

Saguro Cactus

• thicky waxy cuticle

• spines (↓ SA:VOL)

• cells can expand to store water

• deep tap roots

Kangaroo Rat

• burrowing animal (in day)

• ↓ urine

Tropical adaptation

Kapok tree

• rapid growth →tall →↑ sunlight

• wide butress roots: ↑ support

Orchid mantis

• mimcry- looks like flower so can eat insaect polinators