Bark refers to
phellem + phellogen + phelloderm
periderm + cortex
phellem + phelloderm + secondary phloem
periderm + cortex + pericycle + secondary phloem
D.
periderm + cortex + pericycle + secondary phloem
Bark is a loose term and is used to define all the tissues outside vascular cambium. It is the outermost layer of stems and roots of woody plants. It is further differentiated into outer bark or rhytidome (consisting of dead cells) and inner bark (of living cells, i.e., periderm, cortex, pericycle and secondary phloem). The outer layer of the bark are being constantly peeled off on account of the formation of new secondary vascular tissues in the interior. Bark is insect repellent, decay proof, fire-proof and acts as a heat screen.
The outermost limiting layer of mycoplasma is made up of
cell wall
cell membrane
mucilaginous sheath
slime layer
Which of the following statements about Spirogyra is correct?
Lateral conjugation takes place in homothallic species
Scalariform conjugation takes place in homothallic species.
Lateral conjugation takes place in heterothallic species
The type of conjugation is unrelated to homothallic and heterothallic species
Which of the following is true?
Umbel is a racemose inflorescence where all stalked flower aggregate on the flat receptacle
Raceme is a racemose inflorescence having main axis shortened & flower born acropetally
Spadix is a racemose inflorescence having pendulous spike with main axis much flattened.
Spike is a racemose inflorescence having sessile flowers
Jute fibres deteriorate quickly because
cellulose content is high
lignin content is high
cellulose content is low
lignin content is low
The branched sclereids present in hydrophytes are
osteosclereids
trichosclereids
macrosclereids
astrosclereids
The enzyme decarboxylase catalyses the following step
conversion of citric acid to cis aconitic acid
fumaric acid to malic acid
oxalosuccinic acid to - ketoglutaric acid
malic acid to oxaloacetic acid
Which ofthe following is true regarding the given electron transport chain?
CoQ Cyt c Cyt aa3 O2
CoQ Cyt c is H+ absorbing site
aa3 O2, H+ yielding site
CoQ Cyt c is H+ yielding site and aa3 O2 is H+ absorbing site
No H+ is absorbed or released