Glossary  (Page 3/18)

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