Communication + Homeostasis Flashcards
Other than a suitable pH and tempreture, what do enzymes need to work at an optimum level?
An aqueous environment that keeps substates and products in solution (eg water)
Freedom from toxins and excess inhibitors
In terms of the enviornment, what is a stimulus?
An environmental change (eg, tempreture change)
How do the activites of a cell alter their own enviornment?
And give an example of a stimulus and response to do with this
Metabolic activities use up substrates, and produce products (possibly toxic)
Stimulus = build up of toxins
Response = removal of toxins
How does the blood help maintain the internal enviornment of the cells?
Removes the waste and toxins
Ensures that all cells are supplied with enough substrates that are needed?
What will a good communication system do?
Cover the whole body
Enable specific / rapid communication
Enable both short / long term responses
What type of communication system allows rapid responses?
Neuronal system
Define Homeostasis
The maintanence of a constant internal environment
Explain positive feedback
A process that increases any change that is detected by the receptors
Explain negative feedback
The process that brings about a reversal of any change in conditions, so an optimum steady state is maintained
Stimulus»_space; receptor»_space; communication pathway»_space; effector»_space; responce
True of false? An ectotherms body tempreture changes with the environmental tempreture, and requires less food
True
How does an ectotherm control their tempreture?
Alters its physiology (moves outside / underground)
Define the term Endotherm
An organism that can use internal sources of heat, such as heat generated from metabolism, to maintain its body tempreture
