Goal 1. Anatomical Entities

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Back to Wood_anatomy_ontology_meeting,_2012_at_NYBG,_agenda

Review existing anatomy/morphology terms and definitions

Cell types related to wood

sieve elements

Definitions from Esau's Anatomy of Seed Plants

sieve element (PO:0025406): A plant cell (PO:0009002) that is part of a portion of phloem (PO:0005417) tissue, has sieve areas (modified pits) in its walls, and lacks a nucleus in its mature protoplast.

Comment: Sieve elements function mainly in longitudinal conduction of organic solutes. Classified into sieve cells (PO:0025415) and sieve tube members (PO:0000289) based on the presence of sieve plates (GO:0097218) and specialization of sieve areas (GO:0097217) in different parts of the cell. Develops from either a cambial initial (PO:0000295) or a procambial cell (PO:0025258).

part_of phloem, participates_in sporophyte stage

sieve cell (PO:0025415): A sieve element in which the sieve areas are not aggregated into sieve plates.

Comment: Sieve areas in sieve cells generally have narrow pores and thin connecting strands, and they are not highly specialized, but instead are fairly uniform throughout the cell wall. Typical of gymnosperms and non-seed vascular plants. Differ from sieve tube members, which have sieve plates and more pronounced specialization of sieve areas.

sieve tube member (PO:0000289): A sieve element that is part of a sieve tube and has sieve areas aggregated into sieve plates.

Comment: Sieve tube members have sieve areas that are specialized into those with wide pores in sieve plates and those with with narrow pores in lateral sieve areas. Sieve tube members may have inclined end walls with compound or simple sieve plates. Typical of angiosperms. Differ from sieve cells, which have less pronounced specialization of sieve areas and no sieve plates.

syn.: sieve tube element, sieve tube segment

part_of sieve tube

New terms for GO

These subcellular components have been added to GO:

• GO:0097217 sieve area
• GO:0097218 sieve plate
• GO:0097219 compound sieve plate
• GO:0097220 simple sieve plate

sieve area: A cell wall part that is a pit-like area in a plant-type cell wall of a sieve element and has as parts pores lined with callose and occupied by strands of protoplasmic material that interconnect the protoplasts of contiguous sieve elements.

is_a cell wall part (GO:0044426), part_of plant-type cell wall (GO:0009505); part_of sieve element (PO:xxxx) - may have to go in comment

sieve plate: A cell wall part that is the part of a wall of a sieve tube member that bears one or more highly specialized sieve areas.

comment: Typical of angiosperms.

is_a cell wall part (GO:0044426), part_of plant-type cell wall (GO:0009505), has_part sieve area (GO:xxxx); part_of sieve tube member (PO:xxxx).

Could add the relation callose deposition in phloem sieve plate (GO:0080165) inheres_in sieve plate.

compound sieve plate: A sieve plate that has as parts several specialized sieve areas in either a scalariform or reticulate arrangement.

comment: Often located on an end wall of a sieve tube member. Unspecialized sieve areas may occur on other parts of the cell.

is_a sieve plate

simple sieve plate: A sieve plate that has as part a single specialized sieve area.

comment: Often located on an end wall of a sieve tube member. Unspecialized sieve areas may occur on other parts of the cell.

Tissue types related to wood

New term for sieve tube

sieve tube, proposed definition: A portion of phloem tissue that has as parts a series of sieve tube members arranged end to end and interconnected through sieve plates.

Comment: A sieve plate (GO:0097218) is part of a sieve tube member.

Develop list of anatomy/morphology terms that are missing

Do we need only wood-related terms, or other terms for woody plants?