Cell theory, prokaryotic and eukaryotic cells

The active, bulk movement of products through the cell membrane is referred to as endocytosis and exocytosis. Larger molecules that cannot diffuse through the lipid bilayer can now pass the membrane due to these processes. Endocytosis is the process through which chemicals are absorbed by cells. Exocytosis is the opposite of endocytosis; it is the […]

Euplectella is a genus of sponges found in the water. Euplectella is commonly called as glass sponges because of the presence of silica spicules. It looks like Venus’ flower baskets. They are numerous in marine water, deep in the ocean. The bodies of these creatures are bent, tubular, basket-like, or vase-like. The canal system is

Eukaryotes (/jukriots, -ts/) are creatures with a nucleus contained by a nuclear envelope in their cells. Eukaryotes are members of the Eukaryota or Eukarya domain; their name is derived from the Greek (eu, “well” or “good”) and (v, “vessel”) (karyon, “nut” or “kernel Eukaryota is one of three realms of life, the other two being

The primary distinction between Euchromatin and Heterochromatin is that Euchromatin is an uncoiled packed form of chromatin that is genetically active. While heterochromatin is a tightly packed version of the chromosomes that is genetically inactive. Under a light microscope, the non-dividing cells of the nucleus are divided into two zones based on the concentration or

The cell was found for the first time in 1655, by an English scientist named Robert Hooke. This was such a significant discovery that it forever altered basic biology theory and research. So, how did the cell get discovered? Robert Hooke was inspecting a dried portion of the cork tree with a crude light microscope.

Toxins are small molecules, peptides, or proteins produced by living cells that, when in contact with or absorbed by tissues, can cause diseases or structural damage. Toxins and enzymes play critical roles in pathogenic bacterial pathogenicity. Toxins can aid in invasiveness, cause cell damage, inhibit cellular processes, or trigger an immune response and damage. What

Entry and exit of small uncharged molecules occur freely through the semipermeable cell membrane, the process of simple diffusion. Passive movement occurs from areas of higher concentration to areas of lower concentration. Transportation of larger molecules by this method is not always possible. Macromolecules in the form of polysaccharides and proteins cannot proceed so easily

It is the step of the protein-synthesis pathway that is responsible for the expansion of nascent polypeptide chains which is known as the elongation. Two-site model: The two-site model proposes that the ribosome has two sites for transfer RNA (tRNA) binding, one of which binds aminoacyl-tRNAs preferentially and another which binds peptidyl-tRNAs exclusively. The findings

Multiple physiological functions are served by halting the RNA polymerase during transcription elongation. Because of the sequence variability of the DNA being transcribed, as well as specific interactions between polymerase and particular DNA sequences, the pause mechanism is dependent on these factors. For example, elongation occurs during translation, a stage in protein biosynthesis in which

Prokaryotic and eukaryotic DNA carry genetic information for prokaryotic and eukaryotic development, function, and reproduction, respectively. Eukaryotes have a membrane-bound nucleus, whereas prokaryotes do not have one. DNA in prokaryotes is double-stranded and circular. Eukaryotic DNA, on the other hand, is double-stranded and linear. The amount of DNA in prokaryotic cells is significantly less than