Phloem

Definition

Phloem is the vascular tissue in plants responsible for the transport of nutrients, particularly sugars produced through photosynthesis. It plays a crucial role in distributing energy throughout the plant.

5 Must Know Facts For Your Next Test

1. Phloem consists of various cell types including sieve elements and companion cells.
2. Phloem transports organic compounds bidirectionally, unlike xylem which only moves water and minerals unidirectionally.
3. In seedless vascular plants, phloem is less specialized compared to angiosperms.
4. Phloem sap mainly consists of water, sugars, amino acids, and hormones.
5. Damage to phloem can severely affect a plant's growth and energy distribution.

Review Questions

• What are the main components transported by phloem?
• How does the directionality of transport in phloem differ from that in xylem?
• What cell types are primarily found in phloem tissue?

Related terms

Xylem:

Vascular tissue responsible for the upward transport of water and minerals from roots to other parts of the plant.

Sieve Elements: Specialized cells that make up part of the phloem and facilitate nutrient transport.

Companion Cells: Cells closely associated with sieve elements that help manage metabolic functions necessary for nutrient transport.