Plant Defences and Diseases Flashcards
Infection and Response (17 cards)
What do plants need mineral ions for?
For growth and to prevent deficiency symptoms
Mineral ions like nitrates are essential for processes such as protein synthesis.
What happens if there is a lack of nitrates in plants?
Causes stunted growth
Nitrates are crucial for protein synthesis, which is necessary for plant development.
What are magnesium ions needed for in plants?
Making chlorophyll
Chlorophyll is essential for photosynthesis.
What deficiency symptoms do plants exhibit when lacking magnesium?
Chlorosis and yellow leaves
Chlorosis is a condition where leaves produce insufficient chlorophyll.
What types of pathogens can infect plants?
Viral, bacterial, and fungal pathogens
These pathogens can cause various diseases in plants.
What is a common pest that can infest plants?
Aphids
Aphids can cause significant damage to plants.
List common signs that indicate a plant has a disease.
- Stunted growth
- Spots on the leaves
- Patches of decay (rot)
- Abnormal growths (e.g., lumps)
- Malformed stems or leaves
- Discoloration
How can infestations of pests be identified?
They are usually easy to spot on the plants
Infestations can be visually observed.
How can different plant diseases be identified?
- Looking up signs in a gardening manual or website
- Taking the infected plant to a laboratory
- Using testing kits with monoclonal antibodies
What is a physical defense that plants have?
A waxy cuticle on leaves and stems
This cuticle serves as a barrier to stop pathogens from entering.
What surrounds plant cells, providing a physical barrier against pathogens?
Cell walls made from cellulose
Cell walls protect against pathogens that may penetrate the cuticle.
What do layers of dead cells around plant stems do?
Act as a barrier to stop pathogens entering
An example is the outer part of bark on trees.
What type of chemical defenses can some plants produce?
Antibacterial chemicals
Examples include the mint plant and witch hazel.
What is an example of a plant that produces poisons to deter herbivores?
Tobacco plants
Other examples include foxgloves and deadly nightshade.
What mechanical defenses do some plants have?
- Thorns and hairs
- Leaves that droop or curl when touched
How do some plants prevent themselves from being eaten?
By mimicking other organisms
For example, the passion flower has spots that resemble butterfly eggs.
What is a unique adaptation of some plants in the ‘ice plant family’?
They mimic stones and pebbles
This adaptation helps to avoid being eaten by herbivores.
