Nicotinamide adenine dinucleotide
Nicotinamide adenine dinucleotide, abbreviated NAD+, is a coenzyme found in all living cell s. The compound is a dinucleotide, since it consists of two nucleotide s joined through their phosphate groups: with one nucleotide containing an adenosine ring, and the more
Flight feather (Milvus milvus) in flight, showing remiges and rectrices
Flight feathers are the long, stiff, asymmetrically shaped, but symmetrically paired feather s on the wing s or tail of a bird ; those on the wings are called remiges (singular remex) while those on the tail are called rectri more
Immune system image of a single neutrophil (yellow), engulfing anthrax bacteria (orange).
An immune system is a collection of mechanisms within an organism that protects against disease by identifying and killing pathogen s and tumor cells. It detects a wide variety of agents, from virus es to more
Tuberculosis
Tuberculosis (abbreviated as TB for tubercle bacillus or Tuberculosis) is a common and deadly infectious disease caused by mycobacteria , mainly Mycobacterium tuberculosis . Tuberculosis most commonly attacks the lungs (as pulmonary TB) but can also affect the central nervous syst more
Chromatophore chromatophores mediate background adaptation on exposure to dark (top) and light environments (bottom).
Chromatophores are pigment -containing and light-reflecting cells found in amphibian s, fish , reptile s, crustacean s, and cephalopod s. They are largely responsible for generati more