SSC MTS EXAM

SSC

BIOLOGY

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
What could be used in a technique for measuring flow rates in phloem?I. PotometersII. Aphid styletsIII. 14CO2
A
I and II
B
I and III
C
II only
D
II and III only
Explanation: 

Detailed explanation-1: -Aphids possess a protruding mouthpiece (called a stylet), which pierces the plant’s sieve tube to allow sap to be extracted. The penetration of the stylet into the sieve tube is aided by digestive enzymes that soften the intervening tissue layers.

Detailed explanation-2: -Aphids don’t suck; rather, the phloem contents are forced into the aphid (thus the phloem is under pressure) and the excess oozes out the anus (honeydew). Thus, aphid studies demonstrate that the phloem is under pressure. Further, the honeydew can be collected and we can identify its composition.

There is 1 question to complete.