Damaged sieve elements are sealed off, but because of the processs that plug sieve plates pores, excuded phloem sap from wounds that sever sieve elements. Exudation of sap enhanced by the inclusion of;

#Question id: 1753

#Unit 4. Cell Communication and Cell Signaling

In the germinal center, B-cells become memory cells under the influence of:

#Question id: 4646

#Unit 11. Evolution and Behavior

The treeʹs horizontal axis is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V—Z) represent various common ancestors. Letʹs say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

Which of the five common ancestors, labeled V—Z, has been least successful in terms of the percent of its derived species that are extant?

#Question id: 10288

#Unit 6. System Physiology – Plant

 If all the ATP are radiolabelled in the cytosol, then predict about radioactivity of each compound.

 a) All enzyme  of glycolysis will be radiolabelled except 2-phophoglycerate and phosphenol pyruvate

 b) 2-phophoglycerate and phosphenol pyruvate are radiolabelled only the next cycle of glycolysis after cytosolic ATP radiolabelling

 c) 1,3 bisphosphoglycerate will be radiolabelled at 1 and 3 both position

 d) 2-phosphoglycerate are not radiolabelled because its enzyme phosphoglycerate mutase active site contain histidine residue exchange phosphate group from 3-phosphoglycerate

 which prediction about radiolabelling is incorrect?

#Question id: 26998

#Unit 10. Ecological Principles

#Question id: 28969

#Unit 7. System Physiology – Animal