3.1 Flashcards
Under what conditions do organisms survive ost effectively
Within their tolerance limits
What are some factors that contribute to an organisms tolerance limits
Body Temperature, water avilablility, Blood glucose levels, carbon dioxide concentration
What does the law of tolerance state
For each abiotic environmental factor, an organism has a range of tolerances within which it can surivive
Outside an organism’s optimum range, what is the zone called where they can still survive but are under stress and the zone at which they cannot survive
Zone of physiological stress, zone of intolerance
How is communication between different organs and systems achieved ti maintain stability
Through nerves and hormones
What is the role of tissue fluid
It surrounds all body cells and maintains a constant composition. This allows the cells to appropriately function as they are able to maintain the conditions needed to survive
Give an example of an organism responding to change
Baceteria can form spores in response to lack of water and may survive in this form for many years until water becomes available
Multicellular plants maintain their water and solute balance through active transport in the roots and by controlling water loss in the leaves by closing the walls of their stomata
What are some tolerance limits of plants
Mineral composition of the soil
light availability
carbon dioxide levels
tempertaure
wind
pH
What is leibigs law
The environmental factor that is in least supply will limit productivity. E.g. if a plant is in an environment with great soil and ample water but low light, productivity will decrease
Explain eutrophication
Eutrophication is a process where a body of water becomes overly enriched with nutrients, particularly nitrogen and phosphorus. This often results from agricultural runoff, wastewater discharge, and other sources of nutrient pollution. The excess nutrients stimulate an overgrowth of algae, known as an algal bloom. As the algae die and decompose, they consume a significant amount of oxygen in the water, leading to a condition called hypoxia, where oxygen levels are too low to support most aquatic life. This can cause the death of fish and other organisms, disrupt ecosystems, and degrade water quality, making it harmful for wildlife and challenging for human use.
Are organisms able to selectively detect + respond to changes in the external environment?
Yes - this ability is crucial for survival
What detects changes in an organism’s environment?
Sensory receptors
What are cells called that detect stimuli
sensory cells
Define stimuli
A physical or chemical change in the environment that leads to a response
Sensory cells convert the location, intensity and ________ of the stimulus into a message that is then relayed to the CNS
Duration
