B16 Adaptations, interdependence and competition Flashcards
(29 cards)
What is a community?
is two or more
populations of organisms.
What is an ecosystem
is the interaction between a
community
of living organisms and their environment. It is also two or more populations of organisms (usually many more) in their environment.
What is a population?
A population is all the organisms of the same or closely-related
species in an area.
What is interdependence and give an example?
All organisms in an ecosystem depend upon each other. If the population of one organism rises or falls, then this can affect the rest of the ecosystem.
A simple food chain is:
grass → rabbit → fox
If the foxes in the
food chain above were killed, the population of rabbits would increase because they are no longer prey to the foxes. As a result the amount of grass would decrease because the increased population of rabbits would be eating it.
Often very small changes to ecosystems have large consequences, which can be difficult to predict. This means that all the organisms in an ecosystem are dependent upon each other. We call this
interdependence.
What is a stable community?
A stable community is one in which the size of the populations of all species remain relatively constant over time. In the example above the amount of grass, and the numbers of rabbits and foxes all remain relatively constant. The different populations are living in a healthy balance with their environment.
What are abiotic factors?
Non-living elements of an ecosystem, such as climate, temperature, water, and soil type.
What are examples of abiotic factors?
Light intensity
Temperature
Moisture levels
Soil pH content
Soil mineral content
Wind intensity and direction
Carbon dioxide levels for plants
Oxygen levels for aquatic animals
What are biotic factors?
Living elements of an ecosystem, such as plants and animals.
Give examples of biotic factors
Availability of food
New predators
New pathogens
Out-competition
What do plants compete over?
Light
Water from the soil
Minerals from the soil.
Space
What is the difference between interspecific and intraspecific competition.
Intraspecific competition means The competition between organisms within the same species.
while
Interspecific competition means
The competition which occurs between organisms of different species for a common resource.
What do animals compete over?
Food
Mates
Territory
What is quadrat?
A quadrat is a square frame used in ecology and geography to isolate a standard unit of area for study. Here’s how they work:
Purpose: Quadrats are used to sample populations of plants or slow-moving animals in a consistent way. They help estimate population size, density, and distribution.
Method: A quadrat is placed randomly or systematically within the study area. The number of individuals of each species within the quadrat is counted. This process is repeated multiple times at different locations.
Data Analysis: The data collected from multiple quadrats are then averaged to estimate the population density or frequency of a species within the entire study area.
Types: Quadrats can vary in size depending on the organisms being studied and the habitat.
What is quantitative sample?
records the number than the type
What does a Quadrat sample?
Number of an individual species - the total number of individuals of one species (eg daisies) is recorded.
Species richness - the number of different plant or animal species is recorded but not the number of individuals within a species.
Percentage cover
How to use a transect?
Choose your transect line: Decide where you want to sample. This might be across an environmental gradient e.g.,from a forest edge to the interior or to investigate changes in species distribution.
Lay out the transect: Use a measuring tape or rope to create a straight line across the area you want to study.
Sampling methods: Sample within a defined width along the line e.g. ,1 meter on either side. This is better for smaller, more numerous organisms like plants or insects.
Data collection: At regular intervals along the transect , record the species present and their abundance. You can estimate abundance using: Frequency: The percentage of quadrats in which a species occurs. Density: The number of individuals per unit area. Percentage cover: The proportion of the quadrat covered by a species.
Environmental data: Record any relevant abiotic environmental factors, such as light intensity, soil pH, or moisture levels, at each sampling point.
Data analysis: Plot your data to show how species distribution changes along the transect. You can correlate species distribution with environmental factors to identify relationships.
What is systematic sampling?
Used where the study area includes an environmental gradient. A transect is used to sample systematically along the environmental gradient across equal intervals.
Structural adaptations of a plant(cactus)
Spines: Instead of leaves, cacti have spines. These reduce the surface area for water loss through transpiration. They also protect the cactus from herbivores.
Succulent Stems: Cacti have thick, fleshy stems that store water. The stem is also green, allowing it to perform photosynthesis.
Waxy Coating: A waxy layer or cuticle covers the stem, reducing water loss.
Shallow, Widespread Roots: Cacti have extensive root systems that spread out widely but remain close to the surface. This allows them to quickly absorb any rainfall before it evaporates.
Ribs or Folds: Many cacti have ribs or folds in their stems, which allow the stem to expand and contract as it absorbs or uses water.
What is an extremophile?
An extremophile is an organism that lives in an extreme environment. An extreme environment is one in which most organisms would find it difficult or impossible to survive. The organisms that live in these places have highly specialised
adaptations. Examples of extreme environments include the Polar Regions, deserts, the deep ocean bed, hot geothermal springs and the tops of our highest mountains.
What are the adaptations of colder climates?
Animals, like polar bears, at the North Pole are adapted to suit these conditions. They have thick white fur for insulation and camouflage. They have acute senses of smell and sight to hunt prey. They have small surface area : volume ratio to minimise heat loss and a thick layer of fat to keep warm.
Penguins at the South Pole have many of the same adaptations. In addition, the male Emperor penguins have evolved to insulate their egg on their feet throughout winter. This is a behavioural adaptation.
How are camels adapted to face the hot conditions.
large, flat feet - to spread their weight on the sand
thick fur on the top of the body for shade, and thin fur elsewhere to allow easy heat loss
a large surface area to volume ratio - to maximise heat loss
the ability to go for a long time without water - they lose very little water through urination and perspiration
the ability to tolerate body temperatures up to 42°C
slit-like nostrils and two rows of eyelashes - to help keep out sand
What are the biggest challenges with living in a desert?
Coping with the lack of water
Stopping body temperature getting too high or low as desert nights are cold
Why do some plant leaves adapt to become smaller?
To stop water loss in dry conditions
What are the 3 types of adaptations
Structural adaptations: These are physical features of an organism’s body that help it to survive in its environment. Examples include the thick fur of a polar bear or the long neck of a giraffe.
Behavioural adaptations: These are the actions or behaviours that an organism exhibits to survive. Examples include migration, hibernation, or hunting strategies.
Physiological adaptations: These are internal, often unseen, adaptations related to the function of an organism’s body. Examples include the ability of camels to conserve water or the production of venom by snakes.
