B4.1 - Adaptation To Evironment Flashcards
(27 cards)
What is a habitat?
Geographical and physical location where an organism or species lives.
What factors are included in defining a habitat?
Physical location (e.g., tropical forest), geographical location (latitude + altitude), ecosystem type (e.g., desert), and abiotic conditions such as soil type, light levels, temperature, and water availability.
What is an adaptation?
A structural, physiological, or behavioural trait that improves survival in specific abiotic conditions.
What are examples of sand dune adaptations in Marram Grass?
• Lives in dry, salty, shifting sand (low water availability)
• Thick waxy cuticle: ↓ water loss
• Sunken stomata with hairs: traps moist air ↓ transpiration
• Rolled leaves: trap humid air ↓ exposure to wind
• Extensive root system: anchors in sand & absorbs moisture
What are adaptations of the Red Mangrove tree?
• Lives in waterlogged, saline, anoxic soil (low O₂ & high H₂O)
• Pneumatophores (breathing roots): absorb O₂ from air
• Salt excretion glands in leaves: remove excess salt
• Prop/cable roots: provide stability in soft mud
• High solute concentration in roots: draws in water via osmosis
What abiotic factors affect species distribution?
• For animals: temperature, water availability, oxygen, salinity
• For plants: temperature, salinity, light, soil pH, mineral content
What is species distribution?
Where species are found based on whether abiotic factors are within their range of tolerance.
What is a limiting factor?
Abiotic variable that restricts the survival or distribution of a species.
What is the Law of Tolerance?
For each abiotic factor, organisms have:
• An optimal range (ideal conditions)
• A zone of stress (survival but ↓ fitness)
• A zone of intolerance (organism cannot survive)
What is a transect?
A line that spans several different levels of a specific variable (e.g., altitude) to study species distribution.
What is a line transect?
Species are recorded along a line.
What is a belt transect?
Quadrats are placed continuously or at intervals along the line, and the abundance of organisms within each is recorded.
What are the conditions required for coral reef formation?
• Shallow water (<50 m): so light reaches symbiotic algae — zooxanthellae
• Clear water (low turbidity): to allow sunlight
• Warm temperature (23–29°C)
• Slightly alkaline pH
• Stable salinity (~35 ppt)
Why does coral bleaching occur?
When tolerance ranges are exceeded, e.g. due to ocean warming or acidification.
What abiotic factors determine terrestrial biomes?
- Temperature
- Rainfall
What is a biome?
A group of ecosystems with similar abiotic factors in different geographical areas.
Why do biomes have similar communities?
Due to convergent evolution — unrelated species evolve similar traits due to similar environmental pressures.
What are the features of the tropical rainforest biome?
Constant high temperature (25–30°C), no seasons, high rainfall all year (2000–4000 mm), high humidity.
Example: Amazon
What are the features of the taiga biome?
Long cold winters (-10 to -40°C), short summers (~15°C), 2 seasons, low–moderate rainfall (300–850 mm).
Examples: Canada, Russia
What are the features of the tundra biome?
Very low temperatures (below -50°C), short summers (5–10°C), low rainfall (<250 mm/year), permafrost soil.
Example: Arctic
What are the features of the hot desert biome?
Hot days (35–50°C), cold nights (0°C), low rainfall (<250 mm/year).
Example: Sahara
What are the features of the temperate forest biome?
Warm summers (20°C), cold winters (10°C), moderate to high rainfall (750–1500 mm/year), 4 clear seasons.
Example: Europe
What are the features of the grassland biome?
Hot summers, cold winters, low rainfall (~1000 mm/year), 4 seasons.
Example: USA
What are adaptations of the Saguaro cactus?
• Water storage in stem
• Spines instead of leaves (↓ transpiration & protection from herbivores)
• Thick waxy cuticle (↓ water loss via evaporation)
• Widespread & shallow roots (absorbs rainwater quickly)
