Cell biology or cytology is a branch of biology that deals with studies related to the structure and function of a cell-based on the concept that the cell is the fundamental unit of life.
Simple diffusion definition Simple diffusion is a type of passive transport which, as the name suggests, is simply the movement of solute which occurs when its electrochemical potentials on the two sides of a permeable barrier are different. While in … Read more
Facilitated diffusion definition Facilitated diffusion is the process of biological transport in which specific structural components of biological membranes interact with particular solutes or classes of solutes, markedly increasing the rates at which they can cross the membrane. It is … Read more
Cilia and Flagella Definition Cilia and Flagella are complex filamentous cytoplasmic structures protruding through a cell wall. They are minute, especially differentiated appendices of the cell. Flagella (singular = flagellum) are long, hair-like structures that extend from the plasma membrane … Read more
Definition of animal cell Animals are a large group of diverse living organisms that make up to three-quarters of all species on earth. With their ability to move, to respond to stimuli, respond to environmental changes and adapt to different … Read more
Plastids Definition Plastid is a double membrane-bound organelle involved in the synthesis and storage of food, commonly found within the cells of photosynthetic plants. Plastids were discovered and named by Ernst Haeckel, but A. F. W. Schimper was the first to provide a … Read more
Plasmodesmata Definition Every living cell in a higher plant is connected to its living neighbors by fine cytoplasmic channels, each of which is called a plasmodesma which passes through the intervening cell walls. They act like tunnels running through the … Read more
What are Platelets (Thrombocytes)? Platelets (Thrombocytes) Definition Platelets or thrombocytes are anucleated cells derived from the megakaryocytic cells in the bone marrow that, besides being one of the key players in maintaining hemostasis, are involved in developing non-hemostatic immune functions. … Read more
What are Monocytes? Definition of Monocytes Monocytes are cells of the immune system that represent immune effector cells with chemokine receptors and pathogen recognition receptors that circulate through blood or remain localized in lymphoid organs. These cells account for about … Read more
Peroxisomes Definition Peroxisomes are small, membrane-enclosed cellular organelles containing oxidative enzymes that are involved in a variety of metabolic reactions, including several aspects of energy metabolism. They are considered as an important type of microbody found in both plants and … Read more
What are Basophils? Definition of Basophils Basophils are nonphagocytic granulocytes that are the least common leukocytes occurring in the blood circulation and are critical to the immune response against parasites. Basophils are similar to eosinophils in that these are produced … Read more
What are Eosinophils? Definition of Eosinophils Eosinophils are motile phagocytic cells that play an important homeostatic role in providing defense against parasitic infections. Eosinophils are bone marrow-derived granulocytes that remain in the bloodstream for a shorter period of time and … Read more
Vesicles Definition Cells must be able to move molecules, digest particles, and secrete materials in order to survive. For many cellular functions, vesicles are used. It is a small, spherical compartment that is separated from the cytosol by at least … Read more
Image Source: Freepik Company S.L. Similarities of Endocytosis and Exocytosis Endocytosis and exocytosis mechanisms are forms of Active Transport, both using energy to transport particles in and out of the cell. They both have different types similar in that they … Read more
What are Mast Cells? Definition of Mast Cells Mast cells are cells of the immune system of the hematopoietic lineage that remain widely distributed in vascularized tissues throughout the body. Mast cells, unlike other immune cells, do not remain in … Read more
What are Dendritic Cells? Definition of Dendritic cells Dendritic cells are key antigen-presenting cells of the immune system that inform other effector immune cells to fight against invasive pathogens. These are also called professional antigen-presenting cells as these present antigens … Read more
What are Macrophages? Macrophages Definition Macrophages are mononuclear cells functioning as professional phagocytes in order to remove dying, dead or harmful pathogens. Macrophages are a type of white blood cell of the immune system where they engulf and digest particles … Read more
What are Natural Killer (NK) Cells? Definition of NK Cells Natural killer (NK) cells are a group of innate lymphocyte cells with cytolytic activity against virus-infected cells and physiologically stressed cells like tumor cells. Initially, NK cells were described as … Read more
What is Telophase? Telophase is the fifth phase of mitosis and the final phase of meiosis as well. In meiosis, there are two phases of telophase I and telophase II. This is the stage of separation of duplicate genetic materials … Read more
Storage Granules Definition Storage granules are membrane-bounded vesicles containing condensed materials. They are also known as zymogen granules or condensing vacuoles. Storage granules are an important component of metabolism in many organisms spanning the bacterial, eukaryotes and archaeal domains. These … Read more
Buffy Coat Definition A buffy coat suspension is a concentrated suspension of leukocytes and platelets that make up a part of the anticoagulated blood sample obtained by the process of density gradient centrifugation. The term buffy coat arose from the … Read more
What is exocytosis? As compared to endocytosis, exocytosis is a process that is used to transport materials from inside the cell to the external part of the cell by the use of energy. Therefore, it is a type of active … Read more