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Evolution of sex in algae : An overview  In plants, asexual and sexual reproduction are the two main modes of reproduction. Asexual reproduction does not entail sex and does not involve the fusing of any kind of cell or gamete. Spores are a unique form of cell that reproduces in this manner. Every one of these spores has the ability to grow into a new plant. In contrast, when two cells, or gametes, combine during sexual reproduction, a zygote is created that eventually grows into a new plant. Without fusing, individual gametes are normally unable to create new plants. Origin of sex:  The most primitive algae, such as those belonging to the Cyanophyceae (Myxophyceae) family, such as Gloeocapsa and Chroococcus, reproduce by fusion, whereas Oscillatoria, Nostoc, and Anabaena, among others, reproduce vegetatively through the division of a small group of cells known as hormogonia, which subsequently gives rise to new plants through additional division. Certain Cyanophyceae members ...

  Merits and Demerits of Numerical Taxonomy  The process of categorizing organisms using numerical techniques is known as numerical taxonomy. This method firmly clarifies as well as displays the degree of link among the species. Organisms are classified into taxa according to their similarities and differences.  Numerical Taxonomy is at present a very essential part of current systematics. Numerical Taxonomy is also known as Taximetrics; however, presently it is more commonly referred to as Phenetics. It is the Numerical evaluation of the similarities or affinities of taxonomic units, which are typically classified into taxa based on their affinities.  It is also known as Adansonian taxonomy or phenetics.  Robert Sokal and Peter Sneath defined numerical taxonomy.  It is a method of classifying organisms with the help of numerical methods.  In this type of taxonomy, each character is given equal weightage in creating new taxa.  The phenetic similar...

  Classification and Distribution of Gymnosperm in India  Phanerogams are the collective term for gymnosperms and angiosperms (phanero = exposed, gams = sex organs or spermatophytes; sperma = seed). • Plants with bare seeds are known as gymnosperms. The ovules in gymnosperms are openly visible both before and after fertilization. They are not contained by the ovarian wall. of contrast, the ovule or ovules of angiosperms are entirely encased within a structure known as the ovary. For this reason, only naked seeds are produced in gymnosperms instead of fruits, but in angiosperms, seeds are produced inside fruits. • Coulter and Chamberlain (1910) divided gymnosperms into 7 orders. Some of the orders are extinct today.  The seven orders are as follows:  1. Cycadofilicales (extinct)  2. Bennettitales (extinct)  3. Cycadales (Mesozoic to present day)  4. Cordaitales (extinct)  5. Ginkgoales (Palaeozoic to present day)  6. Coniferales (Palaeozoic ...

  Mutation and types of mutagens  A single base change may result in a helpful adaptation, a catastrophic genetic disease, or no effect at all. What causes mutations, and how do they affect a species' future?A single base change may result in a helpful adaptation, a catastrophic genetic disease, or no effect at all. What causes mutations, and how do they affect a species' future? A genetic sequence can change by a mutation. Mutations can involve modifications as minor as the replacement of a single nucleotide base, or building block of DNA, with a different nucleotide base. Larger mutations, on the other hand, can impact numerous genes on a chromosome. In addition to substitutions, DNA sequence insertions, deletions, and duplications can also result in mutations. Certain mutations are inherited when they are inherited from a parent who carries them through the germ line, which is when the mutation is carried by an egg or sperm cell. Somatic mutations are another type of nonher...

  Watson and Crick Model of DNA  Many people think that in the 1950s, English physicist Francis Crick and American biologist James Watson discovered DNA. This is not the situation in actuality. Rather, Swiss chemist Friedrich Miescher discovered DNA for the first time in the late 1860s. Then, in the decades that followed Miescher's discovery, a number of studies conducted by other scientists—most notably,  Phoebus Levene and Erwin Chargaff—uncovered more information about the DNA molecule, including its main chemical constituents and the ways in which they interacted with one another. Watson and Crick may never have come to their ground-breaking conclusion in 1953—that the DNA molecule exists as a three-dimensional double helix—without the scientific groundwork laid by these pioneers. https://educationtechbysapna.blogspot.com/2024/04/structure-and-function-of-cyphellae-and.html The year 1869, albeit little known to most, was a turning point in the history of genetics stud...

  Structure and Function of Cyphellae and cephalepodia in Lichens      Cyphellae ( photobionts)   are smooth- surfaced depression in the thallus of lichen and are responsible for exchange of the gases.  A minute, rimmed, cup-like depression or pore, found in lichens of the genus Sticta, which is visible in the lower surface of the thallus as a small white pit.               cephalepodia  (Mycobiont)   A number of lichens have an alga as the major photobiont but with a cyanobacterium present as a minor photobiont in discrete pockets and such pockets are called cephalepodia.  The basic structure of a lichen is like that of the popular peanut butter cup candy. A layer of photobionts (the peanut butter) is held within a matrix of fungal fibers or hyphae (the chocolate). This allows the photobionts access to sunlight as well as protection from drying out. https://educationtechbysapna.blogspot.com/2024/03/gly...

https://educationtechbysapna.blogspot.com/2024/03/lichens-structure-and-function-of.html   The Ultimate Guide to Different Types of Dietary Fats    One of the three macronutrients that give the metabolic system the energy it needs to run properly is fat. Both unsaturated (good fat) and saturated (bad fat) fats are vital components of our daily diet and are required for our continued health. The foods we eat include both unsaturated and saturated fats. Two different kinds of fats:  You must examine the two types of dietary fats—saturated and unsaturated—in greater detail in order to comprehend the function that fats play in a healthy diet. (Trans fats, a third type, are virtually nonexistent in American diet.)   Saturated:  This fat is referred to as "bad" fat. Animal foodstuffs like beef and pork as well as high-fat dairy products like butter, margarine, cream, and cheese are the main sources of it. A lot of quick, processed, and baked items including pizza...

 Cilia and Flagella : A comparative analysis  Although they have similar structures, flagella and cilia are two different kinds of cell organelles that have different lengths and functions. Within each cell, there are hundreds of short and many cilia. Contrarily, there are fewer and longer flagella (often one to eight) per cell. Despite having the same structural makeup, motile cilia and eukaryotic flagella can have different beating patterns. Cell exterior features called flagella and cilia mainly facilitate cell motility. Some cells have a huge number of short, hair-like projections called cilia covering their surface. Only one end of a cell contains the long, thread-like structures called flagella.                Unlike flagella, which beat separately, cilia beat in unison. Only eukaryotic cells contain cilia. Both prokaryotic and eukaryotic cells have flagella. Undulipodia organisms have both motile cilia and flagella. The primary fu...

  Glyoxysomes and their purposes  Plant microbodies called glyoxysomes are different from peroxisomes and are involved in certain aerobic pathways in plants, such as fatty acid oxidation and the glyoxylate cycle. In plant cells, lyoxysomes are crucial for seed germination. Unlike peroxisomal enzymes, which emerge later in plant development, active glyoxysome enzymes are present in the microbodies from the very beginning.  https://wwpa.hvldks.com/redirect-zone/ee8dada0 https://educationtechbysapna.blogspot.com/2024/03/lichens-structure-and-function-of.html The primary sources of superoxide and H2O2 generated during the β-oxidation of fatty acids during the catabolism of store lipids in germinating seeds are the enzymes glycolate oxidase and urate oxidase in glyoxysomes. Glyoxysomes appear in the first few days after  seed germination  in  endosperm  cells and associate closely with  lipid  bodies. They disappear after the storage fats are brok...