Habitats Flashcards
(19 cards)
Define habitat.
A habitat is the environment in which a community, species, population or organism normally lives
The interaction between a community and its abiotic environment (habitat) forms an ecosystem
List characteristics that can be used to describe a habitat.
Geographical Location: The physical area an organism inhabits.
Physical Conditions: Environmental factors like temperature, light, soil type, and water availability.
List the components of a habitat.
Biotic Factors:
* Living elements (plants, animals, fungi, microorganisms).
* Include predation, competition, mutualism, and other interactions.
Abiotic Factors:
* Non-living elements (temperature, light, water, soil, air).
* Often define habitat boundaries and which organisms can survive there.
What are abiotic factors?
Non-living components of an ecosystem, such as temperature, water availability, salinity, and soil type.
Outline the adaptations of Marram grass to live in sand dune environments.
Sand dunes are characterised by low levels of loosely-packed sediment with reduced nutrient levels and minimal water availability.
Marram grasses have horizontal underground stems (rhizomes) to maximise root penetration and stabilise the plant.
Its root system is deep and extensive to improve anchorage and access to deeper reservoirs of underground water.
Leaves are curled to reduce exposure of stomata to external air (reducing transpiration loss in windy conditions).
Outline the adaptations of a mangrove tree that lives in a muddy swapms.
Mangrove swamps are characterised by waterlogged soils with low oxygen availability and high levels of salinity.
Mangroves may have parts of their roots above ground (aerial root system) to take in oxygen for cell respiration.
Certain parts of a mangrove plant (e.g. stems or leaves) may contain salt glands which actively eliminate salt.
Explain the range of tolerance.
Each species has an optimal range of abiotic factors within which it can thrive.
Conditions outside this range lead to stress or intolerance, making survival or reproduction impossible.
List abiotic variables that affect plant species distribution.
- Temperateure
- Water availability
- Light intensity
- Soil pH and nutrients
List abiotic variables that affect animal species distribution.
- Temperature
- Water availibility
What are the zones on a range of tolerance?
Optimal Zone: Ideal for growth and reproduction.
Stress Zone: Survival possible, but reproduction is limited.
Intolerance Zone: Conditions are lethal; the species cannot survive.
State are the key abiotic limiting factors and their role in distribution.
Temperature: Influences enzyme activity and metabolism.
Water Availability: Too little or too much can hamper survival.
Light Intensity: Critical for photosynthesis and animal visibility.
Soil pH/Salinity: Affects nutrient availability and water uptake.
Oxygen Levels: Essential in aquatic habitats, where oxygen solubility changes with temperature.
List conditions required for the formation of coral reefs.
Optimal depth for light penetration: coral can only survive at shallow depths where sufficient light can penetrate for the algae to photosynthesise
Water clarity: water must be clear enough for light to penetrate
Temperature: heat stress can lead to bleaching
Salinity: stable salinity is necessary for osmotic balance
Low pH: low pH conditions reduce the availability of carbonate ions the coral needs to build their calcium carbonate exoskeletons
Define biome.
A biome is a geographical area that has a particular climate and sustains a specific community of plants and animals.
Biomes consist of many ecosystems that all contain similar communities due to convergent evolution.
State the two abiotic factors that are the principal determinants of biome distribution.
1. Temperature:
Influence on Metabolism and Growth
* Warm regions (e.g., tropics) foster rapid plant growth and high biodiversity due to abundant energy.
* Cold regions (e.g., tundra) limit plant growth and species diversity because metabolic activities slow in low-temperature environments.
Impact on Ecosystem Productivity
* Higher temperatures generally boost photosynthesis and nutrient cycling, resulting in lush vegetation.
* Lower temperatures restrict these processes, often yielding more sparse and specialized communities.
2. Rainfall
* Water is vital for all living organisms; varying levels of rainfall create gradients of vegetation density.
* The timing of rainfall influences growing seasons and the life cycles of organisms.
State key climate characteristics of major biomes.
1. Tropical forest
high temperature
high levels of precipitation
high levels of diversity in both animal and plant species
2. Temperate forest
moderate temperatures with clear seasonal changes
high level of biodiversity
3. Taiga
cold and icy with a small amount of precipitation
dominated by coniferous trees and there is little variation in species
4. Desert
extreme temperatures, very low precipitation and minimal rainfall
consist of a small number of well-adapted species
5. Grasslands
moderate temperatures with wet and dry seasons
not enough water for significant tree growth, communities consist of grazing animals and some predators
Outline the adaptations of an animal living in a hot desert.
The Fennec Fox
Avoiding Heat
* Nocturnal: Hides in cool dens by day, active at night.
* Large ears radiate body heat, aiding cooling.
Adaptations for Movement
* Hair-covered footpads protect from scorching sand.
Water Conservation
* Gains most water from food, minimizing need for free water sources.
Outline the adaptations of a plant living in a hot desert.
The Saguaro Cactus
Minimizing Water Loss
* Thick waxy cuticle reduces transpiration.
* Spines instead of leaves lower surface area and deter herbivores.
Water Storage and Collection
* Wide-spreading root system plus a deep taproot ensure maximum water uptake.
Outline the adaptations of an animal living in a tropical rainforest.
The Spider Monkey
Mobility in the Canopy
* Long arms and legs allow agile climbing.
* Prehensile tail serves as a fifth limb for balance and gripping.
Diet
* Feeds primarily on fruit and seeds, plentiful in the tropical rainforest canopy.
Outline the adaptations of a plant living in a tropical rainforest.
The Yellow Meranti
Competition for Sunlight
* Grows over 100 meters tall to outcompete neighbors for light.
Support Structures
* Buttressed trunk stabilizes in shallow, rainforest soils.
* Smooth bark sheds rainwater quickly, preventing fungal growth.
