Table of Contents
What is the difference between constitutive and induced defenses?
Both types are achieved through similar means but differ in that constitutive defenses are present before an herbivore attacks, while induced defenses are activated only when attacks occur.
Are constitutive defenses always present?
Constitutive defenses are always present in the plant, while induced defenses are produced or mobilized to the site where a plant is injured. There is wide variation in the composition and concentration of constitutive defenses and these range from mechanical defenses to digestibility reducers and toxins.
What are inducible defenses?
Inducible defenses are responses activated through a previous encounter with a consumer or competitor that confer some degree of resistance to subsequent attacks.
What are two chemical defenses of plants?
Chemical defenses : Formed by chemical compounds stored, like phenolics, terpenoids, and alkaloids, and released under attack. Antinutritive defenses include chemical, toxins, defensive proteins, enzymes, and resin deposits that can flow to repel or physically trap small organisms.
What are constitutive defenses?
Constitutive defences include mechanical barriers such as in animals, the skin and gut walls in addition to preformed antimicrobials in vertebrates [2], the phenyloxydase cascade in invertebrates [4], alongside numerous plant toxins that generally act constitutively [5].
Why might an organism evolve an inducible defense instead of a constitutive defense?
Inducible defenses are responses activated through a previous encounter with a consumer or competitor that confer some degree of resistance to subsequent attacks.
What is the difference between constitutive defense and induced defense in plants?
Constitutive defences include mechanical barriers such as in animals, the skin and gut walls in addition to preformed antimicrobials in vertebrates [2], the phenyloxydase cascade in invertebrates [4], alongside numerous plant toxins that generally act constitutively [5].
What are two types of plant defenses?
Both types are achieved through similar means but differ in that constitutive defenses are present before an herbivore attacks, while induced defenses are activated only when attacks occur.
What are three plant defenses?
There are two main types of plant defenses: constitutive and induced. Constitutive – A constitutive defense is one that is always present in the plant. Most plant defenses are constitutive.
What do spines barbs and thorns help protect plants against?
Constitutive defences include mechanical barriers such as in animals, the skin and gut walls in addition to preformed antimicrobials in vertebrates [2], the phenyloxydase cascade in invertebrates [4], alongside numerous plant toxins that generally act constitutively [5].
What are 2 ways plants defend themselves?
The first line of defense in plants is an intact and impenetrable barrier composed of bark and a waxy cuticle. Both protect plants against herbivores. Other adaptations against herbivores include hard shells, thorns (modified branches), and spines (modified leaves).
What are some examples of chemical defenses?
Table 3. Chemical Defenses of Nonspecific Innate ImmunityDefenseExamplesFunctionChemicals and enzymes in body fluidsDigestive enzymes and bileKill bacteriaLactoferrin and transferrinBind and sequester iron, inhibiting bacterial growthSurfactant in lungsKills bacteria16 more rows
What is the advantage of adopting an induced defense over a constitutive defense?
Inducible defenses allow plants to be phenotypically plastic. This may confer an advantage over constitutive defenses for multiple reasons. First, it may reduce the chance that attacking insects adapt to plant defenses
What is a constitutive defense?
Inducible defenses are responses activated through a previous encounter with a consumer or competitor that confer some degree of resistance to subsequent attacks.
How do defense mechanisms evolve?
Constitutive (continuous) defenses include many preformed barriers such as cell walls, waxy epidermal cuticles, and bark. These substances not only protect the plant from invasion, they also give the plant strength and rigidity.
What is a constitutive defense in plants?
Constitutive (continuous) defenses include many preformed barriers such as cell walls, waxy epidermal cuticles, and bark. These substances not only protect the plant from invasion, they also give the plant strength and rigidity.
What are the 3 types of plant defenses?
Inducible defenses are responses activated through a previous encounter with a consumer or competitor that confer some degree of resistance to subsequent attacks.
What are the plant defenses?
The first line of defense in plants is an intact and impenetrable barrier composed of bark and a waxy cuticle. Both protect plants against herbivores. Other adaptations against herbivores include hard shells, thorns (modified branches), and spines (modified leaves).
What is the most common type of plant defense?
Plant defenses include tough, thick, indigestible leaves, along with spines, thorns, stinging hairs (Figure 9.6), and poisons (secondary compounds) produced in the plant tissues.
What defenses do plants have?
Plants have evolved many secondary metabolites involved in plant defense, which are collectively known as antiherbivory compounds and can be classified into three sub-groups: nitrogen compounds (including alkaloids, cyanogenic glycosides, glucosinolates and benzoxazinoids), terpenoids, and phenolics.
How could plants defend themselves?
Constitutive (continuous) defenses include many preformed barriers such as cell walls, waxy epidermal cuticles, and bark. These substances not only protect the plant from invasion, they also give the plant strength and rigidity.
How do thorns protect plants?
Thorns represent the modification of an axillary shoot system in which the leaves are reduced and die quickly and the stems are heavily sclerified and grow for only a limited time (determinate growth). Thorns appear to protect the plant against herbivores
In what ways are Thorn and spines useful to a plant explain?
Explanation: The leaf of the plants or cactus modified into the spines or thorns to reduce the water loss from the plant body. To reduce loss of water means they need to reduce the pores of the leaves so the desert plant changed their leaves to the spines or thorns to reduce the pores and reduce the water loss.
What type of plant will actually eat insects as a defense?
Some plants have actually turned the tables on insects and not only defend against them, but eat them. One example is the venus flytrap which has a trap that looks like leaves. If a fly, or other insect, happens upon its leaves, it will quickly snap the trap close and then release enzymes to digest the insect.
What do you call the spines and thorns of some plants which they use to protect themselves from danger?
Acacia collinsii: The large thorn-like stipules of Acacia collinsii are hollow and offer shelter for ants, which in return protect the plant against herbivores. Modified leaves on a cactus: The spines on cactus plants are modified leaves that act as a mechanical defense against predators.
