Plant adaptations for protection Flashcards
Name some harmful environmental conditions that plants are subjected to
Plants are subject to a large range of potentially harmful environmental conditions. These include being eaten by herbivores, being infected with disease-causing micro-organisms, losing water and the danger of overheating.
Plants have a number of adaptive features, what categories do these get separated into?
To protect themselves, plants have a large number of adaptive features. Some of these features are anatomical (or structural); others are chemical.
What is the most basic adaptive protective feature for plants?
Plants are enclosed by a physical barrier consisting of epidermis or bark.
Plants are enclosed by a physical barrier consisting of epidermis or bark. What does this do for the plant? (2)
These protective layers prevent the entry of pathogens and reduce the loss of water from the plant.
What can the epidermis be covered by? (also a protective anatomical feature)
In addition, the epidermis is often covered with a protective cuticle.
In some plants the epidermis can be adapted to have what form of protective features?
In some plants, the epidermis cells are adapted to form thorns (e.g. blackberry bushes or stinging hairs (e.g. nettle leaves).
A shortage of water in a plant can cause what to happen to the guard cells?
A shortage of water in a plant causes the guard cells to shrivel.
A shortage of water in a plant causes the guard cells to shrivel. What effect does this have on the stomata of the plant? What does this, therefore, do as a protective feature?
This has the effect of closing the stomata and therefore reducing any further loss of water by transpiration.
What does excessive heat do to a plant? (chemical protective feature)
Excessive heat may cause plant enzymes to lose shape and become denatured. This may harm or even kill plants. Many plants form special heat-shock proteins once the temperature rises above about 40°C.
What do many plants form once the temp rises above 40degrees C.
Many plants form special heat-shock proteins once the temperature rises above about 40°C.
What do the heat-shock proteins do once produced as a result of high temps? Why do they do this?
These heat-shock proteins normally surround other proteins (especially enzymes) and help them to maintain their shape.
When a plant is infected by a micro-organism the plant is sometimes able to produce what?
When a plant is infected by a micro-organism the plant is sometimes able to produce stress proteins.
What are some stress proteins called that are produced when a plant is infected by a micro-organism?
Some of these stress proteins are called phytoalexins.
What are phytoalexins?
stress proteins produced by plants
What are the three main actions of stress proteins?
Stress proteins act in different ways, some of which include:
- Damaging the micro-organisms by attacking their cell walls
- Stimulating the formation of specialised plant cell walls that prevent the spread of the micro-organism.
- Stimulating nearby plant cells to respond to the micro-organism.
