Taxes + Kinesis Flashcards
What is a stimulus?
A detectable change in environments
What is a receptor?
A receptor is a detector for changes in the environment
What happens when taxes occur?
Taxes involve organisms moving their entire bodies towards favourable stimulus/away from unfavourable stimulus
How do organisms increase their chances of survival?
Organisms increase their chances of survival by responding to stimuli through different response mechanisms
What are taxes and kinesis?
Taxis and kinesis are simple responses that keep organisms within favourable conditions of their environment
What are different examples of taxes?
Positive phototaxis = towards light
Negative chemotaxis = negative chemotaxis
What is the movement of an organism towards a stimulus known as?
What is the movement of an organism away from a stimulus known as?
Movement towards a stimulus = positive taxis
Movement away from a stimulus = negative taxis
What is an example of a positive taxis? (bacteria)
Bacteria show positive taxis (chemotaxis), where they move towards certain chemicals to aid survival
What is an example of a negative taxis? (earthworms)
Earthworms show a negative taxis (phototaxis), where they move towards light. They will move towards dark environments, to help them avoid dehydration, predators and locate food
What happens when kinesis occurs?
Kinesis involves organisms changing speed of movement and the rate they change direction
Is kinesis directional or non directional response?
Kinesis involves an animal responding to a stimulus but not directionally
What will happen when an organism move from an area of beneficial stimuli to harmful stimuli, involving kinesis?
If an organism moves from ana rea of beneficial stimuli to an area of harmful stimuli. The kinesis response will be an increase rate of changing direction so to return to the favourable conditions quickly
What will happen if an organism is surrounded by negative stimuli, involving kinesis?
If an organism is surrounded by negative stimuli, the rate ofn turning will decrease to keep it moving in a relatively straight line to increase the chances of it finding a new location with favourable conditions
What is an example of kinesis? (woodlice)
Woodlice respond to water.
If a woodlouse crossed a border from a damp to dry area, their kinesis response would be turning rapidly to increase the probability of ending back up in the damp area
If the woodlouse was in a completely dry area, the turning rate would decrease so that it would move in a straight line to increase the chances of finding a new damp area
