Topic 5A- Evosystems And Photosynthesis Flashcards
(34 cards)
Read up on definitions for 5A
What is interspecific competition?
What will its affect be on the population size of each species?
Competition between different specific species, where they compete for the same resources in their habitat.
They will reduce as less resources will be available for growth and reproduction in both.
What is intraspecific competition?
Competition within a species.
What is the carrying capacity?
The maximum stable population size which an ecosystem can support with resources.
Which are more abundant usually, prey or predator?
What is the graph for predation like?
Prey, if you think of foxes and rabbits, foxes could eat multiple rabbits, so rabbits must have be in population surplus by a lot.
As prey population increases, more food/resources are available for predators, so the predators population increases as they can prioritise their energy for growth and reproduction.
As the predator population increases, the population size of the prey decreases as they’re consumed.
There’s now less food for the predators, so the population of predators decreases. And so on.
What is distribution affected by?
Abiotic factors (such as light availability or salt conditions)
Biotic factors(interspecific competition). If one species is better adapted than another in an area, they will be able to out compete the other species for resources, better adapted to the conditions of the surrounding environment and will be able to grow and reproduce. The less advantageous species will therefore be deficient of resources and will reduce in population size, the its distribution in that given area will be reduced, they may even have to move.
What is the definition of a niche?
The unique role which ONE species occupies within a habitat. This can only be occupied by ONE species, if more than one species occupies the same niche, one will outcompete another until only one occupies the niche. This includes:
The organisms a species eats, or what its eaten by (biotic)
The oxygen an organism breathes in, the carbon dioxide it breathes out (abiotic).
How can you investigate populations of organisms?
Measuring abundance using quadrants as an estimate.
Measuring the distribution of an organism in an area you’re investigating.
How would you do a unbaised sample?
Do a random sample. Do this by:
Picking a random coordinate based off a grid assignation, and placing the quadrant grid on these coordinated.
How and why would you do a systematic sample?
Why- there may be a large variety of abiotic and biotic features within a particular habitat, and by selecting random areas, you may miss areas which the species are distributed in, and you want to sample ALL abiotic and biotic factors.
How- measure samples in fixed intervals from each other. This could include placing a quadrats along a line (this is called a line transect).
What is it known as when a habitats abiotic factors change gradually from one area to another?
An environmental gradient.
What is a point quadrant?
How do you calculate its percentage cover?
Where are they useful?
A horizontal bar with a series of holes at set intervals, held up by two horizontal poles. Used to investigate plant species.
They’re placed on the ground at random points.
The points are dropped through the holes, and anything it touches is recorded.
Percentage cover is calculated by the number of poles that touch a given species/total number of poles dropped x100.
In areas where the vegetation it particularly dense.
What can be used to investigate the distribution of plant populations?
What types of transects are there?
Transects.
Line- placing frame quadrats next to each other along a line
Belt- placing tape along the transect, anything which touches the tape is recorded.
Interrupted transects- taking measurements at set intervals along a line. You could place frame or point quadrats to do this.
What are the different ways to measure abiotic factors within a habitat?
Climate
Oxygen availability
Solar input
Soil conditions (edaphic factors)
Topography (the shape and features of the earths surface)
Climate-
Temperature: measured using a thermometer
Rainfall: measure using a rain gauge (cylinder attached to a measuring cylinder)
Humidity: el extrinsic hygrometer
Oxygen availability- using an oxygen detector by measuring oxygen content present in water in an aquatic habitat.
Solar input- light sensor
Soil content-
Soil pH: using pH paper or meter after being mixed with water.
Moisture content: measure mass before hand and after putting into an oven (80-100 degrees), to see weight of soil once dried out.
Topography-
Relief (change in height) can be measured by going to different areas and measuring the heights using GPS, or contour lines on a map.
Slope angle-
Clinometer. This is a protractor with a piece of string attached to the centre with a weight attached to the string. Point the flat edge of the protractor to the slope of the hill and the string will land on the slope angle.
What is succession?
The process of environmental change over time
What is primary succession?
When new land is formed or exposed. There is no soil or organic materials to start with however.
For example, a volcano erupts to form a new rock surface. Or sea levels lower to reveal new land.
What is secondary succession?
Where land is cleared of all plants (i.e. by a fire, or deforestation), but soil remains.
Describe the series of primary succession.
Initial conditions are harsh/hostile. There’s no soil to retain water, so not many species are able to colonise this land. Only pioneering species which are SPECIALLY ADAPTED to the harsh environment are able to grow at this time (for example, lichens and moss).
These pioneering species die, and are decomposed to form a basic soil. This can retain water and minerals. This means that new species which are adapted to use soil when growing can grow. The abiotic conditions are changed, and become less harsh. They die and are decomposed and the soil becomes deeper.
More complex species such as grass and small flowering plants can now move in as they can be supported by the environment. They die and are decomposed to form deeper soil. The abiotic conditions change and can support more complex species such as shrubs and small trees to colonise the area.
These die out and are decomposed to form deeper soil. This can then allow for organisms adapted for very deep soil and water/mineral access to colonise. These are large trees.
Throughout this process, when new species move in, they will be in competition and the better adapted will out compete the plants and animals which are already there. This is the dominant species.
As each species moves in, diversity increases.
Eventually an ecosystem will reach a point where it will not become more complex, this is a climax community, where the ecosystem is supporting the most complex and largest community of plants it can. It won’t change much more past this point.
Give examples of the species involved in primary succession of a bare rock to a woodland.
Lichen-Moss-Grass+small flowering plants-shrubs+ferns+small trees-Large trees
Why do different ecosystems have different climax communities?b
They have different abiotic conditions.
In temperate conditions, there is plenty of available water and minerals, with mild temperatures. And the seasons don’t change much
What is the type of climax community formed when an ecosystem is artificially prevented from developing (i.e. human activity)?
Plagioclimax community
How is glucose used to provide energy to cells?
Remember glucose cannot provide direct energy to a cell
Glucose is broken down during respiration, releasing energy to phosphorylate ADP to ATP.
ATP is then used to provide an immediate energy supply to parts of cells in the body which require it for energy requiring processes.
What is a coenzyme?
A molecule which aids the function of an enzyme.
Name the structures found in a chloroplast.
Inner and outer envelope
Thylakoid and thylakoid membrane
Granum (stacked thylakoid)
Stroma
Lamella
Starch grains
