Biotic Describes the living elements of the ecosystem compare with ‘abiotic’
birth control Any method of having a sexual relationship without causing a pregnancy
Biuret test The test for Protein. Add dilute NaOH then a few drops of dilute (1%)Copper
Sulphate. A purple colour indicates protein
Bivalent (in life sciences) A structure made from two homologous chromosomes joined together during meiosis
Bladder Muscular bag that stores the urine which is made continuously in the kidney
Blastocyst The hollow ball of up to 64 cells formed from a zygote in mammal reproduction
Blind spot The part of the retina with no receptors since neurons leave the eye at that point
Blood plasma The matrix of blood tissue, the liquid part of the blood
Blubber A thick layer of fat under the skin to separate the warm body of some mammals from the cold outside
B-lymphocyte A type of white blood cell, made in the bone marrow, found in a lymph node
Bolus A small ball of food which is swallowed and moved down the gullet by peristalsis
Bone marrow A soft tissue in the centre of some bones that makes blood cells
Bowmans capsule Cup shaped structure in the kidney into which the capillaries of the glomerulus fit
Brain The swollen front end of the spinal cord, with a large mass of interconnected neurons from where the body is controlled
Breathing The movement of air from the atmosphere into the lung air spaces and then out again; otherwise called ventilation
Breathing centre Region of the medulla oblongata which controls the depth and rate of breathing
Bronchiole Thin branch of a bronchus that carries air to the alveoli; has no cartilage rings
Bronchitis Disease caused by an inflammation of the bronchi of the lung
Bronchus One of the main air pathways, strengthened with cartilage rings, that carries air into, and through a lung
Budding A type of artificial asexual reproduction when a bud is grafted onto a scion
Bulimia A disease in which a person purposely brings up the food eaten, so losing weight
Caecum Pouched piece of intestine where herbivores digest cellulose, in humans the
appendix.
Calyx The collective term for all the sepals of one flower
Canine tooth The large, pointed "fang" tooth
Capillarity Movement of a liquid up narrow tubes due to surface tension
Capillary The smallest blood vessel with a thin, leaky wall so that liquid can pass out
Capsule The outer protective "skin" around a kidney to hold the tissues in place
Carbohydrate A compound of Carbon, Hydrogen and Oxygen with twice as many Hydrogen
atoms as Oxygen atoms eg C6H12 O6
Carbon fixation Holding the carbon of carbon dioxide gas in the leaf in a new form so it cannot escape; it becomes attached to ribulose biphosphate
Carbon monoxide A poisonous, colourless gas CO: it stops haemoglobin from being able to carry oxygen
Carboxyl The arrangement of atoms -COOH which is found in all organic acids
Carcinogen Any substance that causes a cancer to develop
Carpel One unit of the female reproductive parts of a flower
Cardiac Of the heart
Cartilage Supporting tissue which is softer and more flexible than bone; cells called