In Botany, What Is Septicidal?

Septicidal and loculicidal dehiscence are two types of dehiscence in plants. In lococulicidal dehiscence, the locule wall splits between the septa, leaving the latter intact. In septicidal dehiscence, the split is at the septum that separates the loculi. A true fruit developed solely from the ovary and its contents is known as a fruit. In schizocarpy, the extension of the ovary union between carpels, especially the degree of fusion between carpel flanks, greatly affects the schizocarpy.

Septicidal dehiscence occurs in linseed (Linum) and mustard (Brassica), where the seeds are liberated through the septa or partition wall. In Datura and other plants, the fruits rupture. Capsular fruits are classified by the nature of dehiscence and the mechanism of dehiscence. Septicidal dehiscence involves splitting along the partitions of the seed capsule, dividing into component carpels that open by their ventral suture.

Botanists can distinguish between explosive dehiscence, which flings seeds or spores far from the parent plant, and septicidal dehiscence, which splits along the sutures between adjacent carpels. Both loculicidal and septicidal capsules split into distinguishable segments called valves. In a septicidal capsule, the fruits dehisce by separating between the septa of adjacent carpels.

In summary, dehiscence in plants involves splitting the septa of adjacent carpels, resulting in the development of a fruit. The dehiscence mechanisms vary depending on the type of plant and the type of fruit being produced.

What is an example of a capsule in botany?

A capsule is a dry fruit that opens when ripe, splitting into valves or pores at the top or around the circumference. Additionally, it serves as the spore-forming organ in liverworts and mosses. Examples of such flowers include the iris, poppy, pigweed, and plantain.

What is Thallophyta and its example?

Thallophytes are a group of non-mobile organisms, formerly a sub-kingdom of the kingdom Plantae. They are found in moist or wet places due to their absence of roots and vascular tissue for water and mineral transport. Thallophytes are autotrophic and primarily manufacture their own food, with some members relying on other sources. Their reserve food is typically starch, which is converted into complex compounds after photosynthesis.

Thallophytes have a cellulose cell wall, lack vascular tissue, and have simple, single-celled sex organs. They are divided into two subdivisions: Algae and Fungi. The division of Thallophyta is based on similar characteristics but lacks a common ancestor.

What are the two example of capsule?

Certain capsules, such as those of N. meningitidis Group B and Strep. pyogenes, mimic host polysaccharides, making them recognized as’self’ by the host immune system. These capsules contain sialic acid and hyaluronic acid, respectively. The site uses cookies, and all rights are reserved for text and data mining, AI training, and similar technologies. Open access content is licensed under Creative Commons terms.

What is thallose plant body?

Thaloid bodies represent a distinct category of plant body that lacks the capacity for differentiation into roots, stems, or leaves. Thalloid bodies are also found in algae and some bryophytes, such as the cyanobacterium Chlorella. Liverworts, such as Marchantia, possess a thallus-like body that lacks the typical differentiation into stems, leaves, and roots.

What is sessile and subsessile?

Sessility is a term used in botany to describe plant organs like flowers or leaves that lack a stalk. These parts can also be subsessile, meaning not completely sessile. A sessile flower lacks a pedicel, while a pedicellate flower is not sessile. For example, the Trillium genus is divided into sessile-flowered trilliums and pedicellate-flowered trilliums. In mycology, “sessility” refers to a fungal fruit body that is directly attached to the substrate without a supporting stipe or pedicel.

What is petiolate and sessile?

The petiole is a stalk that connects a leaf to the plant stem, with petiolate leaves being long or short. When absent, the blade attaches directly to the stem, forming sessile leaves. Subpetiolate leaves have an extremely short petiole and may appear sessile. In some plant groups, such as the speedwell genus Veronica, petiolate and sessile leaves may occur in different species. In grasses (Poaceae), the leaves are apetiolate, but the blade may be narrowed at the junction with the leaf sheath to form a pseudopetiole.

In plants with compound leaves, leaflets are attached to a continuation of the petiole called the rachis, with each leaflet attached by a short stalk called the petiolule. Pulvina, swollen regions at either end of the petiole, are common in the bean family Fabaceae and the prayer plant family Marantaceae. A pulvinus on a petiolule is called a pulvinulus.

What is the difference between a capsule and a biofilm?

Bacterial capsules are a large structure found in many bacteria, consisting of a polysaccharide layer outside the cell envelope. This well-organized layer is not easily washed off and can cause various diseases. The capsule is found in both gram-negative and gram-positive bacteria and is different from the second lipid membrane, the bacterial outer membrane, which contains lipopolysaccharides and lipoproteins. When the amorphous viscid secretion diffuses into the surrounding medium, it remains as a loose undemarcated secretion known as a slime layer.

The capsule and slime layer are sometimes summarized under the term glycocalyx. Most bacterial capsules are composed of polysaccharide, but some species use other materials, such as poly-D-glutamic acid in Bacillus anthracis. Capsules are difficult to stain due to their tight packing, making it difficult to visualize encapsulated bacteria using a microscope. To visualize encapsulated bacteria, a sample is treated with a dark stain, such as India ink, as the capsule’s structure prevents the stain from penetrating the cell.

What are the 3 functions of capsule?

Capsules play a crucial role in determining access to the cell membrane, mediating adherence to surfaces, and increasing desiccation tolerance. They are also key virulence determinants in pathogenic bacteria, such as Pasteurella multocida. The nucleotide sequence of the capsule biosynthetic locus, consisting of 15 genes, can be grouped into three functional regions. Regions 1 and 3 encode proteins involved in capsule export, while region 2 encodes proteins involved in polysaccharide biosynthesis.

To construct a mutant impaired in capsule export, the final gene of region 1, cexA, was disrupted by insertion of a tetracycline resistance cassette by allelic replacement. The acapsular phenotype was confirmed by immunofluorescence, and the strain could be complemented and returned to capsule production by the presence of a cloned uninterrupted copy of cexA.

Pasteurella multocida is the causative agent of a wide range of diseases in both wild and domestic animals, causing significant economic losses worldwide. Many P. multocida strains express a polysaccharide capsule on their surface, and isolates can be differentiated serologically by capsular antigens into serogroups A, B, D, E, and F. The disease caused by the organism is generally dependent on capsular type, with serogroups B and E causing hemorrhagic septicemia in cattle and buffalo, serogroup A causing fowl cholera in poultry, and serogroup D causing atrophic rhinitis in pigs.

What is the difference between septicidal and loculicidal?

Loculicidal dehiscence is defined as the splitting of the septa of a fruit, whereby the other half remains intact. Septotomic dehiscence occurs at the septum that separates the loculi and may not be entirely distinct. To illustrate, the septa between Ledum palustre capsules split as the fruit opens, releasing seeds, whereas the septa remain intact in Lagerstroemia capsules.

What is a thallose in botany?

Thalus is a plant-like vegetative body that lacks differentiation into distinct parts, such as a stem, leaves, and roots. Additionally, it does not grow from an apical point, which differentiates it from other plant types. The term is derived from the Greek word “thallos,” meaning “sprout,” and shares similarities with the Armenian “dalar,” which translates to “green,” “fresh,” and the Albanian “dal,” which is comparable to the English word “dale.” The term “thallus” is derived from the Latin word “thallos,” which means “sprout.”

What is an example of a septicidal capsule?

Septicidal capsules split longitudinally along or through the septum, separating two locules. Examples of these capsules can be found in four plant families: Chelone, Datura inoxia, Gelsemium sempervirens, and Yucca filamentosa. Septifragal capsules break away of valves from the septa, leaving a central column. Oenothera and Rhododendron are two of the 15+ plant families that exhibit septifragal dehiscence. Some may describe Oenothera capsules as loculicidal, while Rhododendron capsules are septicidal.

Pyxis is a fruit capsule with circumscissile dehiscence, splitting horizontally along the circumference, causing the top or lid to pop off. Examples include Jeffersonia diphylla and Plantago, both native to the 17+ plant families with pyxides. These capsules are essential for the survival and growth of various plant species.