A chemiosmotic model  has been proposed  to explain Polar transport , following steps are involve in the transport of auxin polarly;

a) IAA enters the cell either passively in the undissociated form (IAAH) or by secondary active cotransport in the anionic form (IAA–)

b) The cell wall is maintained at an acidic pH by the activity of the plasma membrane H+- ATPase

c) In the cytosol, which has acidic pH, the IAAH form predominates

d) The anions exit the cell via auxin anion efflux carriers that are concentrated at the basal ends of each cell in the longitudinal pathway

Which of the following is the correct statements about the polarly transporting of auxin?

TLS Online TPP Program

#Question id: 8893

#Unit 9. Diversity of Life Forms

While sampling marine plankton in a lab, a student encounters large numbers of fertilized eggs. The student rears some of the eggs in the laboratory for further study and finds that the blastopore becomes the mouth. The embryo develops into a trochophore larva and eventually has a true coelom. These eggs probably belonged to a(n)

TLS Online TPP Program

#Question id: 8891

#Unit 9. Diversity of Life Forms

While vacationing in a country that lacks adequate meat inspection, a student ate undercooked ground beef. Sometime later the student became easily fatigued, and lost body weight. At about the same time, whitish, flattened, rectangular objects full of small white spheres started appearing in his feces. Administration of niclosamide cured the problem. The student had probably been infected by a

TLS Online TPP Program

#Question id: 8888

#Unit 9. Diversity of Life Forms

In a small stream, you pick up a rock and observe many small, flattened worms crawling on its undersurface. You decide that they belong to the phylum Platyhelminthes. To which class do they probably belong?

TLS Online TPP Program

#Question id: 8858

#Unit 9. Diversity of Life Forms

Which of these factors, when used to label the horizontal axis of the graph in Figure 33.1, would account most directly for the shape of the plot?

TLS Online TPP Program

#Question id: 8852

#Unit 9. Diversity of Life Forms

The upper forelimbs of humans and bats have fairly similar skeletal structures, whereas the corresponding bones in whales have very different shapes and proportions. However, genetic data suggest that all three kinds of organisms diverged from a common ancestor at about the same time. Which of the following is the most likely explanation for these data?

TLS Online TPP Program

#Question id: 7700

#Unit 9. Diversity of Life Forms

The legless condition that is observed in several groups of extant reptiles is the result of ________.