Lymphocytes are white blood cells making up 18-42% of circulating WBCs. Main types are T cells (cell-mediated immunity) and B cells (humoral immunity). Natural killer cells (NK cells) play role in innate immunity. Lymphocytes have large nuclei and can be classified as small or large
The nucleolus is the largest structure in eukaryotic cell nuclei. It is composed of proteins, DNA, and RNA. Nucleoli form around specific chromosomal regions called nucleolar organizing regions. A diploid human cell can have up to ten nucleolus organizer regions
Centriole is a cylindrical organelle composed mainly of tubulin protein. Found in most eukaryotic cells but absent in conifers and flowering plants. Forms centrosome with bound pair of centrioles surrounded by pericentriolar material. Contains nine sets of microtubule triplets arranged in cylinder
Genus contains about 150 species of unicellular flagellates. Found in freshwater, seawater, and snow as "snow algae". Name comes from Greek "chlamys" (cloak) and "monas" (solitary)
Ribosomes are macromolecular machines found in all cells for protein synthesis. Consists of small (30S) and large (50S) subunits containing rRNA and proteins. First observed by George Palade in 1950s as dense particles
Denaturation occurs when proteins lose their native structure and bioactivity. Can be caused by heat, pH extremes, salt, solvents, or chemical agents. Primary structure remains intact, secondary and tertiary structures are altered. Denatured proteins lose solubility and can aggregate. Enzymes lose their ability to catalyze chemical reactions when denatured