Exam 34: Transport in Plants

Sugars pass from cell to cell in the leaf starting in the _______ of the mesophyll; they move through the _______ of other cells and finally pass into the _______ of the sieve tube element.

The increase in pressure potential at the source end of the sieve tube is caused by the uptake of water.The water enters the sieve tubes through

The HARDY mutation, which biotechnologists have recently integrated into rice plants, has been shown to increase water use efficiency.This genetic modification will help feed an ever-increasing world population by

How are sieve tube elements able to carry out general cellular maintenance while lacking structures such as a nucleus, Golgi apparatus, and ribosomes?

Water initially can move into the root apoplastically or symplastically, but it eventually must cross into the vascular tissue via the _______ route.

Mineral ions dissolved in water move within the stem xylem

According to the pressure flow model, during fruit development, photosynthesizing leaves are the carbohydrate _______ and the fruit are the _______.

The following table shows measurements of water potential at various locations in a 100-foot-tall tree. Based on this information, water in the xylem of this tree will

What are two structures plants use to minimize the loss of water?

The force of _______ might potentially be sufficient to explain the transportation of water in trees, if trees were much shorter and had much smaller xylem vessels.

The major benefit of having xylem cells that are dead and lack cell contents at maturity is in reducing

In order to move between the apoplast and the symplast, water must

How does the electrochemical gradient enable ions (K⁺, for example) to move against its concentration gradient?

Within the leaf, the release of abscisic acid can be triggered by _______.

Which of the following statements about the apoplast (the transport route through intercellular spaces) is true?

Where would you look to find the Casparian strips in a prepared microscope slide of root tissue?

Ion channels directly participate in

In 1893, scientists performed an experiment to determine whether tree roots actively pumped water through the xylem.They discovered that

Guard cells actively transport _______ to affect stoma size.

Water transport through the xylem results from transpiration of water from the leaves and the resulting _______ in the xylem, which pulls water up.