13.1 Coordination Flashcards
What is coordination
When changes occur in an organisms internal or external environments the organism must respond to these changes in order to survive
Examples:
Internal -> blood glucose conc., temp, water potential and cell pH
External -> humidity, temp, light intensity, new/sudden sounds
How do plants and animals react to changes in their internal environment
Animals and plants respond to these changes differently.
Animals react through electrical responses (via neurones) and chemical responses (via hormones).
Plants react through chemical communication systems including hormones.
Why is coordination needed
Organisms need to coordinate the different cells and their different functions.
What is homeostasis
In large, multicellular organisms, different organs have different functions in the body. Therefore, the functions must be coordinated to maintain a constant internal environment.
What is cell signalling
Cell signalling -> nervous and hormonal systems coordinate the activities of whole organisms. This coordination relies on communication at a cellular level through cell signalling
Occurs through one cell releasing a chemical which has an effect on another cell (target cell).
What can happen through cell signalling
Through this process, cells can:
Transfer signals locally; for example, between neurones at synapses.
Transfer signals across large distances using hormones.
What is coordination in plants
plants don’t have nervous systems like animals, however have to still maintain environments. For example, plants grow towards the sun to maximise photosynthesis.
