B4.1 Adaptations to environment

Question 1

What is a habitat?

Answer 1

a habitat is the place where an organism lives, which could be both in terms of its geographical as well as its physical location within an ecosystem.

Question 2

What is the distribution of organisms depend on?

Answer 2

The distribution of an organism in a specific environment depends on both, abiotic & biotic factors. However, it’s mostly abiotic factors to which organisms show specific adaptations.

Question 3

What is a biotic factor?

Answer 3

Biotic factor = “living” factors which have impact on feeding, predator-prey, symbiotic, mutualistic or other forms of interdependent relationships.

Question 4

What is an abiotic factor?

Answer 4

Abiotic factor = “non-living” physical factors. They have an influence on specific adaptations or organisms to live in their respective habitats.

Question 5

What are the condition plants adapt for in high altitude habitat?

Answer 5

Plants growing in high altitude are exposed to many diff types of abiotic stress, e.g. UV radiation, low temp, water scarcity & frozen soil (permafrost) which makes rooting & absorption of nutrients & water difficult.

Question 6

What are the condition plants adapt for in dry habitat?

Answer 6

Plants growing on beach dunes have challenge of water conservation & tolerance of high salt conc which hinders water uptake by osmosis. sand retain little water & it contains little organic matter (which normally helps to store water).

Question 7

What are the condition plants adapt for in waterlogged habitat?

Answer 7

Mangroves swamps develop in tropics & subtropics where they grow under sheltered conditions & where mud accumulates. Soil is waterlogged, anaerobic & with high salt conc (due to evaporation of water).

Question 8

How is the alpine edelweiss adapted for it’s high altitude habitat?

Answer 8

• woolly hair traps air & insulates the plant against low temps
• white hair or pigmentation protects plant against sun & UV radiation

Question 9

How is the alpine moss campion adapted for it’s high altitude habitat?

Answer 9

• small leaves to prevent excessive evaporation of water from the leaves by transpiration
• stunted growth to stay low to the ground protects them from harsh weather conditions

Question 10

How is the alpine cobweb houseleek adapted for it’s high altitude habitat?

Answer 10

• thick and fleshy leaves helps with conservation for the plant growing on rock or when the soil is frozen

Question 11

How is the marram grass adapted for it’s dry habitat?

Answer 11

• thick waxy cuticle reduced water loss through transpiration
• rolled up leaves create a humid chamber and reduces exposure to wind (reducing transpiration)
• underground stems (rhizomes) provide stability and can extend deep into the ground to obtain water
• accumulation of carbohydrates in root and leaf cells –> storage of sugars increases osmotic potential & helps to absorb water

Question 12

How does pneumatophores and cable roots help mangroves adapt to their waterlogged habitat?

Answer 12

• Pneumatophores are vertical roots which grow into air & absorb oxygen
• Cable roots provide stability & often grow close to ground to absorb oxygen

Question 13

How does stilt roots (growing in downwards arch from stem) help mangroves adapt to their waterlogged habitat?

Answer 13

• Anchor the trees into ground & increases stability

Question 14

How does buoyant seeds help mangroves adapt to their waterlogged habitat?

Answer 14

• Can be carried away by ocean currents & allow dispersal to fertile soil

Question 15

How does salt glands in leaves help mangroves adapt to their waterlogged habitat?

Answer 15

• Excess salt removal due to high salt water uptake

Question 16

What is a distribution map?

Answer 16

a distribution map show the distribution of a species where it lives. It reflects the factors that affect species, especially abiotic factors.

Question 17

what abiotic factor which affect distribution by shown on a distribution map?

Answer 17

Animal distribution are affected by abiotic factors e.g. water availability, temp, light intensity, soil pH, soil salinity & availability of mineral nutrients. E.g. butterfly (Glanville Fritinary, Melitaea cinxia) prefers living in hot & dry places. On a distribution of Switzerland, the meadow of lowland areas or narrow valley are preferred habitats.

Question 18

How can one measure a plants range of tolerance of an abiotic factor?

Answer 18

To investigate range of tolerance of an abiotic factor e.g. pH, temp or light intensity, a transect can be used. Diff types of sampling data with transects, two most important = line transect (organisms found at regular sample point are recorded) or belt transect (quadrats are placed at regular sample points & abundance of organisms within each is recorded)

Question 19

What are coral reeds?

Answer 19

Coral reefs are biodiverse marine ecosystems which are only able to develop where conditions are suitable for hard corals. Corals = animals, which share a mutualistic relationship with tiny algal cells called zooxanthellae, form rocky structure of reef. Zooxanthellae perform photosynthesis, so light is required.

Question 20

what are the conditions required for coral reef formation?

Answer 20

• Low depth: less than 50m so that light can penetrate & photosynthesis carried out
• pH: above 7.8 to allow deposition of CaCO3 in coral skeleton
• Salinity: between 32-42 parts per thousands of dissolved ions to avoid osmotic problems
• Clarity: turbidity would prevent penetration of light so water must be clear
• Warm temp: 23-29°C so both coral & its zooxanthellae remain healthy

Question 21

What is a biome?

Answer 21

A biome = biogeographical unit consisting of a biological community, that has formed in response to physical environment in which they are found, & a shared regional climate.

Question 22

What are the two main abiotic factors which determine distribution of terrestrial biomes?

Answer 22

Earth temp & annual rainfall ear two main abiotic factors which determine distribution of terrestrial biomes.

Question 23

What happens to species that live in the same biome?

Answer 23

Species composition of organism living in biomes will vary depending on geographical location, but adaptations are likely to be similar.

Question 24

What is the precipitation, seasonal variation, temp and type of plant community of the tropical biomes?

Answer 24

Precipitation: High
Seasonal variation: Minimal
Temperature: High
Type of plants community: Very high plant biodiversity

Question 25

What is the precipitation, seasonal variation, temp and type of plant community of the temperate biomes?

Answer 25

Precipitation: Medium/High Seasonal variation: Warm summer, cold winters, spring & autumn Temperature: Medium Type of plants community: Deciduous broad-leafed trees which loose leaves in colder season

Question 26

What is the precipitation, seasonal variation, temp and type of plant community of the taiga (boreal) biomes?

Answer 26

Precipitation: Medium/high Seasonal variation: Short summers, long cold winters Temperature: Low Type of plants community: Evergreen forests dominated by conifer trees

Question 27

What is the precipitation, seasonal variation, temp and type of plant community of the desert biomes?

Answer 27

Precipitation: Very low Seasonal variation: Minimal variation Temperature: High Type of plants community: Little vegetation, often with spines for leaves, adapted for water conservation

Question 28

What is the precipitation, seasonal variation, temp and type of plant community of the grassland biomes?

Answer 28

Precipitation: Medium/High Seasonal variation: Dry & cold seasons Temperature: high/Medium Type of plants community: Crass species, little significant trees growth bc of lack of water

Question 29

What is the precipitation, seasonal variation, temp and type of plant community of the tundra biomes?

Answer 29

Precipitation: Medium/Low Seasonal variation: Short summer, very cold winter Temperature: Very low Type of plants community: No trees bc of lack of water & short growing season. Soil is frozen for most of yr --> little growth

Question 30

What are the similar adaptations to the abiotic environment that all plant growing in the tundra share?

Answer 30

- close to ground - small in height - slow growing - have hairs to trap heat - germinate, flower & set seeds within very short growing season - waxy leaves help preserve water - shallow root system helps to avoid permafrost

Question 31

What adaptations do cacti show to life in hot desert?

Answer 31

- wide-spreading root system to collect water up to 30m from stem - deep tap roots that collect water from up to 1m down on subsoil - fat stems with storage tissue to conserve water after infrequent desert rains - pleated stems that allow shrinkage in droughts & swelling after rain - vertical orientation of stems to reduce interception of sunlight at midday & maximize it at cooler times of day - thick waxy cuticle on stem epidermis to reduce transpiration - leaves reduced to spines, to reduce SA for transpiration & prevent herbivores from eating slow growing cactus - CAM metabolism allowing stomata to open at night & close during heat of day, reducing transpiration

Question 32

What adaptations does fennex fox show to life in hot desert?

Answer 32

- nocturnal: it avoids highest temp during daylight hrs - build underground den where it can stay cool during day - long thick hair to provide heat insulation both for cold nights & hot days - hairs covering pads of feet to provide insulation when walking on very hot sand - pale-coloured coat that reflects sunlight ( darker coat = absorb light) - large ears radiate heat & help keep body temp down - variable ventilation rate that can be increased to more than 600 breaths/min (panting) to cause heat loss by evaporation

Question 33

What adaptation does the spider monkey show for life in tropical rainforest?

Answer 33

- long arms & legs for climbing & reaching for fruit - flexible shoulders allowing swinging from tree to tree - large hook-like hands without thumbs that can grasp branches & lianas & pick fruit - feet that can act like extra hands, grasping branches & allowing arms to be used for feeding or other purposes - long tail that can grip onto branches & act like a fifth hand - highly developed larynx allowing a wide range of sounds to be made to communicate in the dense rainforest canopy - sleeping at night & active in daytime when vision is most acute & distances can be judged between branches - breeding at any time of yr as there is a constant supply of fruit, nuts, seed, buds, flowers, insects & eggs

Question 34

What adaptations does Philodendron show for life in tropical rainforest?

Answer 34

- climbing habitats, allowing them to reach sunlight in understory - climb over other plants or climbing trunks of tress with aid of aerial roots - growing habitat can be epiphytic: growing on other plants, hemiepiphytic: growing both on other plants & from soil, rarely terrestrial as epiphytes typically grow on a host plant, absorbing moisture & nutrients from air, rain or surrounding debris -aerial roots: attach itself to tree & collect water & nutrients - drip trips: allow water fall off quickly so can capture as much sunlight as possible - wide/large leaves: helps capture the little light available in dark environment since understory only gets 5% of rainforest sunlight - waxy cuticle: causes water to form discrete droplets rather than spreading out