The order Pennales is a traditional subdivision of the heterokont algae known as diatoms. [1][2] The order is named for the shape of the cell walls (or valves or frustules) of pennate diatoms, which are elongated in valve view.

The order Pennales is a traditional subdivision of the heterokont algae known as diatoms. The order is named for the shape of the cell walls (or valves or frustules) of pennate diatoms, which are elongated in valve view.

The meaning of PENNALES is an order of diatoms having a raphe or pseudoraphe and ornamentation of the valves always bilaterally arranged in relation to a line rather than to a point.

Sep 9, 2023 · Diatoms are microscopic algae that play a vital role in marine ecosystems. They have circular or elliptical to rod-like shapes and are perforated by minute apertures called areola. They are divided into two orders: the Pennales and the Centrales.

Pennate diatoms are bipolar, elongate and bilaterally symmetric, although quite a few taxa are bilaterally asymmetric. Pennate diatoms make up a heterogeneous group that includes araphid, monoraphid, and biraphid taxa. In older taxonomic systems, pennate diatoms are contrasted with the centric diatoms.

Taxonomically, diatoms are divided into two groups based on the symmetry of the cells. Centric diatoms (order Centrales) have radially arranged markings. Pennate diatoms (order Pennales) have markings bilaterally arranged about the valve’s long axis. Figure 3. Diatoms spine extensions (centric) Figure 4.

Diatoms are also divided in to two main Orders, which include the Centrales and the Pennales. Centrales. Also referred to as Biddulphiales, Centrales have the following characteristics: Pennales are also known as Bacillariales and have the following characteristics:

In diatom … have radial markings; the elongated Pennales, which move with a gliding motion, have pinnate (featherlike) markings. Read More

The order Pennales is a traditional subdivision of the heterokont algae known as diatoms. [1][2] The order is named for the shape of the cell walls (or valves or frustules) of pennate diatoms, which are elongated in valve view.

In this article we will discuss about the reproduction in pennales. This will also help you to draw the structure and diagram of reproduction in pennales. Diatom cells multiply usually by a peculiar method of cell division.