Of the Steps Below, Which Would Be Fourth in the Sequence

question 56

Multiple Choice

Of the steps below, which would be fourth in the sequence for the formation of a root nodule?

• A) Bacteroids are formed.
• B) The root produces flavonoids that attract Rhizobium bacteria to the vicinity of the root.
• C) Flavonoids trigger transcription of the bacterial nod genes.
• D) The plant produces leghemoglobin.
• E) Nod factors secreted by the bacteria cause cell division leading to the formation of primary nodule meristem.

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Definitions:

Pleural Cavity

The thin fluid-filled space between the two pleural membranes surrounding each lung, providing lubrication during breathing.

Pleura

The thin, protective membranes surrounding the lungs and lining the inner chest wall, facilitating smooth movement of the lungs during breathing.

Pleurisy

An inflammation of the pleurae, which are the layers of tissue lining the lungs and inner chest wall, often causing sharp chest pain with breathing.

Pleural Cavity

The thin fluid-filled space between the two layers of the pleura surrounding the lungs, providing lubrication during respiratory movements.