Biology

Chloroplasts are small organelles inside the cells of plants and algae. They are the food producers of the cell. They absorb light to make sugar…

The chromosomes of a cell are in the cell nucleus. They carry genetic information. In the nucleus of each cell, the DNA molecule is packaged…

The cell membrane is a thin flexible layer around the cells of all living things. It is a double layer of lipids and proteins that…

Apoptosis is the controlled death of a cell. It is a form of programmed cell death, or “cellular suicide”. It plays an integral part in…

Inferior Vena Cava (IVC) Definition: Inferior vena cava (or IVC) is a large vein that carries de-oxygenated blood from the lower body to the heart.…

Oxidative Stress (Effects: Health, Biological, and Chemical) Definition: Oxidative stress reflects an imbalance between free radicals and antioxidants in our body. It occurs when excess oxygen radicals…

DNA repair (Mechanisms) Definition: DNA repair mechanisms comprise relatively simple single-step enzyme reactions catalyzed by monomeric proteins which directly reverse base damage to DNA. In…

DNA repair (Damage and Sources) Definition: DNA repair, any of several mechanisms by which a cell maintains the integrity of its genetic code. In human…

Meiosis (Functions and Importance) Definition: Meiosis (/maɪˈoʊsɪs/; from Greek μείωσις, meiosis, which means lessening) is the process in eukaryotic, sexually-reproducing animals that reduces the number…

Meiosis (Phases) Definition: Meiosis (/maɪˈoʊsɪs/; from Greek μείωσις, meiosis, which means lessening) is a specialized form of cell division that produces reproductive cells, such as…

Respiratory System (Anatomy) Definition: The respiratory system (also referred to as the ventilator system) is a complex biological system comprised of several organs that facilitate…

Pulmonary Alveolus Definition: Pulmonary alveolus (plural: alveoli, from Latin alveolus, “little cavity”), informally known as air sac, is any of the innumerable minuscule, thin-walled, capillary-rich…