biology topic 1

Aneurysm

A localised weakening and bulging of the wall of an artery due to loss of elastic tissue

Angina

Chest pain caused by reduced blood flow to the heart muscle, usually due to narrowed coronary arteries

Anticoagulant/ platelet inhibitory drugs

Drugs that reduce blood clot formation by preventing clotting factors or inhibiting platelet aggregation

Antioxidants

Molecules that prevent oxidation by neutralising free radicals, reducing cell damage

Atheroma

A fatty deposit within the inner lining of an artery

Atherosclerosis

A disease in which atheromas build up in arteries, narrowing them and reducing blood flow

Basal metabolic rate (BMR)

The minimum rate of energy expenditure required to maintain vital functions at rest

Blood pressure

The force exerted by blood against the walls of arteries

Body mass index (BMI)

A measure of body mass calculated as mass/ height squared, used to assess healthy weight

Cardiac cycle

The sequence of events in one complete heartbeat, including systole and diastole

Cardiovascular disease (CVD)

Diseases affecting the heart and blood vessels

Case-control studies

Observational studies comparing individuals with a disease to those without to identify risk factors

Cholesterol

A lipid used in membrane structure and hormone synthesis; excess LDL cholesterol increases CVD risk

Cohort studies

Long-term studies following a group to investigate links between lifestyle factors and disease

Collagen

A fibrous protein providing tensile strength in tissues such as blood vessels

Coronary arteries

Arteries that supply oxygenated blood to the heart muscle

Coronary heart disease (CHD)

A condition caused by narrowed coronary arteries reducing blood supply to the heart

Diastole

The relaxation phase of the cardiac cycle when the heart fills with blood

Double circulatory system

A system where blood passes through the heart twice per complete circuit of the body

Elastic fibres

Fibres that allow tissues to stretch and recoil, maintaining blood pressure

Glycosidic link/ bond

A covalent bond formed between monosaccharides during condensation

Heart attack/ myocardial infarction

Death of heart muscle due to blockage of coronary arteries

Hypertension

Persistently high blood pressure

Oedema

Accumulation of tissue fluid causing swelling

Positive feedback

A mechanism where the output amplifies the original stimulus

Risk factor

A factor that increases the likelihood of developing a disease

Saccharides (mono, di, poly)

Carbohydrates made of one, two or many sugar units

Saturated fats

Lipids with no double bonds between carbon atoms

Single circulatory system

Blood passes through the heart once per complete circuit

Smooth muscle

Muscle found in blood vessel walls that controls vessel diameter

Sphygmomanometer

An instrument used to measure blood pressure

Statins

Drugs that lower blood cholesterol by inhibiting cholesterol synthesis in the liver

Stroke

Brain damage caused by interruption of blood supply

Systole

The contraction phase of the cardiac cycle

Thrombosis

Formation of a blood clot within a blood vessel

Tissue fluid

Fluid formed from plasma that surround cells

Triglyceride

A lipid made of glycerol and three fatty acids

Unsaturated fats

Lipids containing one or more double bonds between carbon atoms