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 the orderly sequence of events that coordinates and regulates the cell proliferation ( when it will divide and how and so will not become malignant). there are certain cells that have lost the capacity for division  RBC muscle cell  neurons certain cells that have the capacity of division but do not divide until getting stimulation: fibroblast cells lymphocytes hepatocytes POTENCY the body of a multicellular organism develops, cell specialise. this process of specialization is called DIFFERENTIATION. the specialised cells from tissue that have a specific function. these specialized cells lose the ability to divide. cells that retain the ability to divide by mitosis are potent. cell potency: the ability of cells to divide by mitosis giving rise to a further type of cells. TOTIPOTENT CELLS ability to make all cell types in the body and cell types that are important for the development of embryos for eg. zygotes in humans. PLURIPOTENT CELLS ability to make all cell types in...

Plants are complex organisms composed of a variety of specialized cells and tissues, each with unique functions and structures that work together to maintain the plant's overall health and survival. Understanding plant tissues and their functions is crucial for understanding the growth, development, and physiology of plants. In this blog, we will explore the different types of plant tissues and their roles in maintaining plant structure and function. Dermal Tissue Dermal tissue is the outermost layer of cells in a plant and is responsible for protecting the plant from physical damage and water loss. The dermal tissue is made up of epidermal cells, which form a continuous layer that covers the entire surface of the plant, including leaves, stems, and roots. These cells have a thick cuticle, which is a waxy layer that reduces water loss, and they also have specialized structures called stomata, which regulate gas exchange between the plant and the environment. Ground Tissue Ground ti...

The mutation is a fundamental process in biology, as it drives genetic variation and evolution. Mutations are changes in the DNA sequence that make up the genetic material of an organism. These changes can affect a single nucleotide or an entire chromosome, and they can have a range of effects on an organism's phenotype or observable characteristics. There are several types of mutations, each with different causes and effects. Some of the most common types of mutations include: Point Mutations Point mutations are changes in a single nucleotide in the DNA sequence. These mutations can result in the substitution of one nucleotide for another, and they can have a range of effects on the encoded protein. Some point mutations can have no effect on the protein, while others can cause it to become non-functional or to function abnormally. Frameshift Mutations Frameshift mutations are insertions or deletions of nucleotides in the DNA sequence that cause a shift in the reading frame of the ...

Recombination is the process by which genetic material from two different sources is combined to form a new, unique combination of genes. This process occurs in a variety of organisms, from bacteria to humans, and it is an essential aspect of biology, driving genetic diversity and evolution. There are several mechanisms of recombination, including: Sexual Reproduction Sexual reproduction is the most common mechanism of recombination in multicellular organisms. During sexual reproduction, the genetic material from two individuals is combined to form a unique offspring. This process results in offspring that inherit a mix of genes from both parents, leading to genetic diversity and variation. Crossing Over Crossing over is a mechanism of recombination that occurs during meiosis, the process of cell division that leads to the formation of eggs and sperm. During meiosis, the chromosomes that carry the genetic material align and exchange segments of DNA, leading to a recombination of geneti...

DNA replication is the process by which cells duplicate their genetic material in preparation for cell division. This is a crucial process that allows cells to maintain their genetic information and pass it on to their offspring. In eukaryotes, DNA replication occurs in a complex and regulated manner, involving multiple proteins and enzymes. Steps of DNA Replication in Eukaryotes Initiation The first step of DNA replication in eukaryotes is initiation, during which the DNA double helix is unwound and the two strands are separated. This is accomplished by helicase enzymes, which break the hydrogen bonds holding the two strands together. Primer Synthesis Once the DNA strands are separated, the next step is primer synthesis, during which short RNA primers are synthesized by primase enzymes. These primers serve as starting points for the extension of new DNA strands. Elongation The next step is elongation, during which the DNA polymerase enzymes extend the primers, adding new nucleotid...

DNA replication is the process by which cells duplicate their genetic material in preparation for cell division. This is a crucial process that allows cells to maintain their genetic information and pass it on to their offspring. DNA replication is a complex and regulated process that involves multiple proteins and enzymes working together. Steps of DNA Replication Initiation The first step of DNA replication is initiation, during which the DNA double helix is unwound and the two strands are separated. This is accomplished by helicase enzymes, which break the hydrogen bonds holding the two strands together. Primer Synthesis Once the DNA strands are separated, the next step is primer synthesis, during which short RNA primers are synthesized by primase enzymes. These primers serve as starting points for the extension of new DNA strands. Elongation The next step is elongation, during which the DNA polymerase enzymes extend the primers, adding new nucleotides to the growing DNA strands. Th...

 CHROMOSOMES transmission and expression of genetic information. a centromere which is most evident at metaphase where it is the narrowest part of the chromosome and the region at which spindle fibres attach. replication origins certain DNA sequences along each chromosome at which DNA replication is initiated. telomeres are the end of a linear chromosome that has a specialized structure to prevent internal DNA from being degraded by nucleases.     BACTERIAL CHROMOSOME appears as a distinct clump, the nucleoid , which is confined to a definite region of the cytoplasm. if a bacterial cell is broken open gently, its DNA spills out in a secret of twisted loops. the ends of the loops are most likely held in place by protein. many bacteria contain additional DNA  6in the form of circular molecules called plasmids. EUKARYOTIC CHROMOSOME individual eukaryotic chromosomes contain enormous amount of DNA  and consists of a single, extremely long molecules of DNA. ...

 What are Living Organisms Made Up of?  living organisms are made of cells. cells are capable of independent existence and performing the essential function of life. viruses  are non cellular because they lack cell like structures. robert hook  first observe cork cells under  microscope  in 1665 leeuwenhook first oberves single celled organism in 1674 pasteur discovered microbial fermentation in 1856 pasteur disapproved spontaneous generation in 1862 koch determine causative agents for many bacterial infection during period of 1876-1906. smallest cell: mycoplasma (PPLO- pleuro pneumonia like organism, about 10 micrometer in size) longest cells : nerve cell largest cell: ostrich cell What is a Cell Made Up of? What is the Structural Organisation of a Cell? protoplasm : nucleus+ cell membrane +cytoplasm  cytoplasm: all content except nucleus (contain organalles) nucloplasm: nucleus+ its content cytosol : fluid where cytoplasm suspended. PLASMA MEMBRANE ...