Coral Reefs: Definition, Types, Formation and Economic Importance
Coral colonies grow continuously in size by budding of polyps and often form extensive masses, known as coral reefs.
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Aurelia aurita: Classification, Morphology and Life cycle
Aurelia aurita is easily recognised by its soft bell or umbrella-shaped body with four red or purple horseshoe-shaped gonads on its upper surface and four long and narrow oral lobes hanging downward from the lower surface.
Phylum Coelenterata: Definition, Characteristics, Classification and Examples
Phylum Coelenterata (Gr., koilos = hollow ; enteron = intestine), also known as Phylum Cnidaria, is a group of aquatic, mostly marine animals characterized by a simple body structure with a single opening serving as both mouth and anus. Members of this phylum have a diploblastic body (two tissue layers: ectoderm and endoderm) and radial symmetry. They possess specialized stinging cells called cnidocytes containing nematocysts, used for defense and capturing prey. Coelenterates exhibit two main body forms: the sessile polyp (e.g., Hydra) and the free-floating medusa (e.g., jellyfish). This phylum includes organisms like corals, sea anemones, and hydroids, playing important roles in marine ecosystems, such as reef-building.
Differences between Apoptosis and Necrosis
The main difference between apoptosis and necrosis is the way in which cell death occurs. Apoptosis is a programmed and controlled process of cell death that plays a vital role in normal development, tissue maintenance, and removing damaged cells. It does not cause inflammation as the cell contents are contained and recycled. Necrosis, on the other hand, is an uncontrolled and unplanned cell death caused by injury, infection, or toxins, often leading to inflammation as the cell contents are released into the surrounding tissue.
Canal System in Sponges
Inside the body of Sponges, the water current flows through a certain system of spaces collectively forming the canal system in sponges.
Differences between Innate and Adaptive Immunity
The main differences between Innate and Adaptive Immunity lies in their response mechanisms and specificity. Innate immunity is the body’s first line of defense and provides a rapid, non-specific response to infections. It includes physical barriers (like skin), chemical barriers, and immune cells like macrophages. In contrast, adaptive immunity is specific to particular pathogens and develops over time, involving specialized cells like T and B lymphocytes that create memory for future immune responses.
Differences between Somatic and Germ Cells
The main differences between somatic and germ cells is their function and role in reproduction. Somatic cells are the body cells that make up the tissues and organs of an organism and are involved in growth, repair, and maintenance. Germ cells, on the other hand, are specialized cells that give rise to gametes (sperm and egg cells) and are involved in sexual reproduction.
Differences between Dominant and Recessive Alleles
The main differences between dominant and recessive alleles is how they affect the expression of a trait. A dominant allele is expressed in the phenotype even if only one copy is present (heterozygous condition), while a recessive allele is only expressed when two copies are present (homozygous condition).
Bacterial Culture Media: Definition, Composition and Classification
Bacterial Culture Media Bacterial culture media are nutrient-rich substances designed to support the growth, proliferation, and maintenance of bacterial populations in a controlled laboratory environment. One of the most important reasons for culturing bacteria in vitro is its utility in diagnosing infectious diseases. Isolating a bacterium from sites in the body normally known to be … Read more
Phylum Porifera: Definition, Characteristics, Classification and Examples
Phylum Porifera is a group of simple, multicellular, aquatic animals commonly known as sponges. They are characterized by their porous body structure, which allows water to circulate through specialized channels, enabling them to filter-feed by extracting nutrients and oxygen from the water. Most sponges are marine, though some are found in freshwater. Porifera are among the most ancient animal groups, with a simple organization that makes them pivotal to understanding the evolution of multicellular organisms.