sieve tube

Thus about 60% of the minor vein network lacks sieve tubes.

This increases the hydrostatic pressure of the sieve tube elements.

This creating pressure that pushes the sap down the sieve tube.

As a result, concentration of sucrose increases in the sieve tube elements.

They have a narrower diameter and are more elongated compared to sieve tube members.

After this, last year's sieve tubes are crushed.

Vessels and sieve tubes frequently touch each other.

Companion cells (arrowed) differentiate from the same mother cell as sieve tubes.

Sieve tube members have no cell nucleus, ribosomes, or vacuoles.

Sieve tubes are formed from sieve-tube members laid end to end.

Forisomes are proteins occurring in the sieve tubes of Fabaceae.

These new sieve tubes often developed in the interfascicular area adjacent to the wounded bundles.

Each companion cell is derived from the same mother cell as its associated sieve tube member.

Now they are unable to move back, but can proceed through wider plasmodesmata into the sieve tube element.

Experiments to demonstrate bidirectional movement in a single sieve tube are technically very difficult to perform.

Some experiments indicate that bidirectional movement may occur in a single sieve tube, whereas others do not.

The phloem contains both normal and nacreous-walled sieve tubes that may be functional.

No structural evidence exists for cytoplasmic streaming in mature sieve tubes based on an actin–myosin system.

Water moves out of the sieve tube cells by osmosis, lowering the hydrostatic pressure within them.

Some argue that mass flow is a passive process while sieve tube vessels are supported by companion cells.

The first early-phloem sieve tubes are formed at the end of May and loaded with sugars during June.

Striga sieve tubes develop along with the osculum.

Phloem consists of two cell types, the sieve tubes and the intimately associated companion cells.

Hydrostatic pressure moves the sucrose and other substances through the sieve tube cells, towards a sink.

The gradient of sugar from source to sink causes pressure flow through the sieve tube toward the sink.