metabolism germination 2

What are the early signals produced by stress exposure?

• Change in intracellular Ca2+, secondary signaling molecules such as inositol phosphate, and ROS accumulation

• Secondary signaling molecules such as inositol phosphate, activation of kinase cascades, and lipid peroxidation

• Change in intracellular Ca2+, activation of kinase cascades, and DNA repair

• Activation of kinase cascades, DNA repair, and lipid peroxidation

What is the main source of ROS during seed germination?

• β-oxidation pathway in glyoxysomes

• Extracellular peroxidases

• NADPH oxidases of the plasma membrane

• Mitochondrial electron transport chain

Which molecule is recognized as an important signaling molecule and can diffuse easily through membranes?

• Ca2+

• H2O2

• ROS

• Inositol phosphate

What is the most frequently oxidized base in RNA during seed germination?

• Thymine

• Cytosine

• Guanine

• Adenine

Which phytohormones act as negative regulators of seed germination?

• Jasmonic acid and Salicylic acid

• Auxins

• Gibberellins

• Brassinosteroids

What is the key mechanism for coping with early abiotic-stress conditions during seed germination?

• Increase in ABA levels

• Activation of GA biosynthesis

• Stimulation of protein synthesis

• Crosstalk relation between seed dormancy and germination

What inhibits water uptake by preventing cell wall loosening of the embryo?

• Abscisic acid

• Gibberellins

• Jasmonic acid

• Salicylic acid

Which enzymes are involved in the degradation of endosperm starch during seed germination?

• Lactate dehydrogenase

• α-amylase and β-amylase

• Dehydrogenases

• Succinate dehydrogenase

What is the main source of energy and carbon source for the growing embryo during seed germination?

• Glucose

• NADH

• Storage lipid breakdown product

• Stored ATP

Which hormone is involved in direct enhancement of the growth of the embryo during the late phase of germination?

• Abscisic acid

• Salicylic acid

• Jasmonic acid

• Gibberellins