which of the following is a net sugar source for a deciduousangiosperm tree?

A. new leaves in early spring

B. fruits in summer

C. roots in early spring

D. roots in early autumn

Which type of mutant would be most likely to produce a bushierphenotype?

A. strigolactone underproducer
B. auxin overproducer
C. cytokinin underproducer
D. strigolactone overproducer
E. gibberellin overproducer

Which of the following observations provides the strongestevidence against root pressure being the principal mechanism ofwater transport in the xylem?

A) Not all soils have high concentrations of ions.
B) Root pressure requires movement of water into the xylem fromsurrounding cells in the roots.
C) Over long distances, the force of root pressure is not enough toovercome the force of gravity.
D) There is no water potential gradient between roots andshoots.

During the night time, due to lack of transpiration, the waterpotential within the vascular cylinder ____________.

A. lowers due to accumulation of minerals

B. increases due to accumulation of minerals

C. lowers due to loss of minerals

D. increases due to loss of minerals

Mammalian eyes sense light because the photoreceptor cells havemolecules called opsins, which change structure when exposed tolight. Which of the following plant molecules would be analogous tomammalian opsins in their light-sensing ability?

A. auxin and phytochrome

B. auxin and Pfr

C. Pfr and phytochrome

D. cytokinins and phototropins

I need to know the reasons for the answers to thesequestions. Thank you in advance!