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Question 1

What is the apoplast, and why is it important in plants?

Answer 1

The apoplast is the space outside the plasma membrane, allowing free movement of materials like water and solutes. It is crucial for diffusion across tissues or organs.

Question 2

What are Casparian bands, and how do they function in plant defense?

Answer 2

Casparian bands are cork-like structures in vascular tissues that create a waterproof barrier, preventing bacterial invasion.

Question 3

How do rhizobium bacteria benefit plants?

Answer 3

Rhizobium bacteria form symbiotic relationships with plants by fixing atmospheric nitrogen into a form usable by the plant, aiding growth.

Question 4

Why do some plants reject their own pollen?

Answer 4

Some plants prevent self-pollination at the stigma to encourage genetic diversity and reduce inbreeding.

Question 5

What chemicals do plants produce to combat environmental stresses?

Answer 5

Plants excrete various chemicals to counteract stresses like drought, heat, and insect attacks, improving their adaptability.

they can detect species of animal that are eating them

Question 6

What is a bacterioid, and what role does it play in nitrogen fixation?

Answer 6

A bacterioid is a transformed bacterium in nitrogen-fixing plants, adapted to facilitate nitrogen fixation in anaerobic conditions.

they cant live without their host

Question 7

What is leghemoglobin, and why is it significant?

Answer 7

Leghemoglobin removes oxygen to maintain the anaerobic conditions needed for nitrogen fixation in plant root nodules.

Question 8

How do endomycorrhiza and ectomycorrhiza differ?

Answer 8

Endomycorrhiza penetrates plant cell walls without entering cell membranes, while ectomycorrhiza forms external interactions.

Question 9

What are biotrophs, and how do they differ from necrotrophs?

Answer 9

Biotrophs feed on living cells and are highly specialized, while necrotrophs kill plant cells and feed on dead tissue.

Question 10

What is a hemi-biotroph?

Answer 10

A hemi-biotroph exhibits a lifestyle that starts with biotrophy (feeding on living cells) and transitions to necrotrophy (feeding on dead cells).

Question 11

What role do nematodes play in plant root systems?

Answer 11

Nematodes signal for cell growth in vascular tissues and extract nutrients, often causing damage to the plant.

they remain dormant in the soil until they sense a root

Question 12

What distinguishes oömycetes from fungi?

Answer 12

Oömycetes are protists with fungal-like characteristics but lack hyphal septa (seperating parts of the hypha with cell walls), being unicellular instead.

Question 13

What determines a plant’s susceptibility to pathogens?

Answer 13

being susceptable means a pathogen can affect the plant in some direct negative way. non susceptable means it cant even detect the plant as a soure of food.

Question 14

What are resistance genes (R-genes) in plants?

Answer 14

R-genes enable plants to recognize specific pathogen effectors and trigger defense mechanisms to combat infection.

Question 15

How do effectors suppress plant defenses?

Answer 15

Effectors are pathogen-produced molecules that disrupt the plant’s defense response by suppressing crucial steps. they can make it so the plant feeds the pathogen.

Question 16

What is phytoalexin, and how does it aid plants?

Answer 16

Phytoalexin is an antibacterial compound produced by plants to resist bacterial infections.

Question 17

How do plants detect fungal infections?

Answer 17

Plants detect fungal infections by recognizing chitin, a structural component in fungal cell walls, triggering defense responses.

chitin

Question 18

What is the significance of the nitrogen cycle in plants?

Answer 18

The nitrogen cycle provides plants with essential nitrogen in usable forms like nitrate or ammonium, crucial for growth.

you need nitrogen to make proteins and dna

Question 19

What is mycorrhiza symbiosis?

Answer 19

Mycorrhiza is a mutualistic relationship where fungi assist plants in nutrient uptake (like phosphorus), and plants provide carbohydrates in return.

Question 20

What are the two types of mycorrhiza?

Answer 20

The two types are endomycorrhiza, which penetrates cell walls, and ectomycorrhiza, which forms external associations.

Question 21

How do plants resist necrotrophic pathogens?

Answer 21

Plants produce defensive chemicals and strengthen their cell walls to limit pathogen spread and damage.

they can also kill off any infected parts to save the rest

Question 22

What is the role of appressoria in fungal infections?

Answer 22

Appressoria are specialized fungal structures used to penetrate plant tissues by generating high turgor pressure.

Question 23

What is a haustorium, and which pathogens use it?

Answer 23

A haustorium is a structure formed by biotrophic pathogens to extract nutrients from living plant cells without killing them.

Question 24

What is RNA interference (RNAi) in plants?

Answer 24

RNAi is a defense mechanism where plants degrade double-stranded RNA from viruses to prevent infection.

Question 25

What are the physical defenses of plants?

Answer 25

Plants use barriers like cuticles, trichomes, and spines to deter herbivores and pathogens. | raphides zijn micro splinters die schade veroorzaken als je het op eet

Question 26

What are induced plant defenses?

Answer 26

Induced defenses are activated in response to an attack, such as producing phytoalexins or reinforcing cell walls.

Question 27

What are parasitic plants, and how do they affect crops?

Answer 27

Parasitic plants, like Striga, extract nutrients from host plants using haustoria, often reducing crop yields. | plants growing on other plants

Question 28

What is the significance of quorum sensing in bacterial infections?

Answer 28

Quorum sensing allows bacteria to coordinate infection strategies based on their population density.

Question 29

What is a hypersensitive response in plants?

Answer 29

The hypersensitive response is a localized cell death mechanism to prevent pathogen spread.

Question 30

What is induced systemic resistance?

Answer 30

Induced systemic resistance is a plant-wide defense response triggered by beneficial microbes or minor infections.

Question 31

How do viruses spread within plants?

Answer 31

Viruses move through plasmodesmata and vascular tissues to infect different parts of the plant.

Question 32

What are biotic and abiotic stresses in plants?

Answer 32

Biotic stresses include pathogens and herbivores, while abiotic stresses involve drought, temperature extremes, and salinity.

Question 33

What is translocation in plants?

Answer 33

Translocation is the movement of sugars and nutrients through the phloem to support growth and development.

Question 34

What is the role of trichomes in plant defense?

Answer 34

Trichomes are hair-like structures that deter herbivores and reduce water loss.

Question 35

How do pathogens use effectors to bypass plant defenses?

Answer 35

Effectors suppress specific plant immune responses, enabling pathogens to invade.

Question 36

What are necrotrophic effectors?

Answer 36

Necrotrophic effectors are molecules that kill plant cells, creating nutrients for necrotrophic pathogens.

Question 37

How can breeding increase plant resistance?

Answer 37

Breeding introduces resistance genes or strengthens general defenses to improve a plant's ability to withstand pathogens.

Question 38

What is the significance of systemic acquired resistance?

Answer 38

Systemic acquired resistance provides long-term immunity throughout the plant after a localized infection.

Question 39

What is the role of cuticles in plant defense?

Answer 39

The cuticle is a waxy layer that protects plants from water loss and pathogen entry.

Question 40

What are macro and micronutrients in plants?

Answer 40

Macronutrients like nitrogen, phosphorus, and potassium are needed in large amounts, while micronutrients like zinc and iron are required in smaller quantities but are equally essential for plant health. | macro stikstof fosfoor kalium, micro zink ijzer

Question 41

What is the role of stomata in abiotic stress responses?

Answer 41

Stomata regulate gas exchange and water loss. During stress like drought, they close to minimize water loss while balancing carbon dioxide uptake.

Question 42

How does pH affect nutrient availability in soils?

Answer 42

Soil pH influences the solubility of nutrients, with certain nutrients becoming unavailable to plants in highly acidic or alkaline conditions. the roots swap out electrolytes with its own particles to extract them from the soil

Question 43

What is the significance of the nitrogenase enzyme?

Answer 43

Nitrogenase catalyzes the conversion of atmospheric nitrogen (N₂) into ammonia (NH₃) during nitrogen fixation, a critical process for plant nutrition.

Question 44

What are cleistothecia and oöspores in fungal pathogens?

Answer 44

Cleistothecia are closed fruiting bodies of some fungi, while oöspores are thick-walled sexual spores of oömycetes, both aiding in survival.

Question 45

How do nematodes manipulate plant roots?

Answer 45

Nematodes induce gall formation in roots and extract nutrients, often weakening the plant.

Question 46

How does induced systemic resistance differ from systemic acquired resistance?

Answer 46

Induced systemic resistance is triggered by beneficial microbes, while systemic acquired resistance follows pathogen attack, both providing whole-plant immunity.

Question 47

What is the role of secondary metabolites in plants?

Answer 47

Secondary metabolites like alkaloids and flavonoids defend against herbivores and pathogens and mediate environmental interactions.

Question 48

How do plants use phytohormones in stress responses?

Answer 48

Phytohormones like abscisic acid, salicylic acid, and jasmonates regulate responses to biotic and abiotic stresses.