Glossary

An A-Z of keywords and phrases, all of which are relevant to the post-16 biology curriculum.

 

A B C D E F G H I J K L M N O P Q R S T U V W Y Z
B cells

Named after the bone marrow, where immature B cells are produced. Types include plasma B cells and memory B cells. A type of lymphocyte.

Bachelor’s degree

A course of study that leads to a qualification such as a BSc (Bachelor of Science) or BA (Bachelor of Arts). Generally, these take three to four years’ full-time study, although medicine degrees can take six years. Some universities, including Oxford, Cambridge and Dublin, award a BA regardless of the subject studied.

Bacterium (plural: bacteria)

One of the three domains of life, bacteria are single-celled prokaryotic organisms.

Balanced diet

A diet that contains a range of foods with nutrients in the correct proportions to help someone be healthy, including having a healthy weight.

Basal

Describes the side of the cell in relation to its position in the body; the basal membrane faces away from the outside surface of the body or the lumen of internal cavities.

Base pair

Two DNA bases paired up, like rungs on a ladder, which produces the double helix structure.

Basophils

Cells involved in allergic and inflammatory responses. Basophils release histamine like mast cells, but unlike mast cells they circulate in the blood. A type of white blood cell.

Beige fat

A type of adipose (fat) tissue. Beige fat cells are brown fat cells that can emerge in ordinary white fat in response to certain triggers, like extreme cold.

Binary fission

A method of prokaryotic asexual reproduction that produces two identical cells.

Biobanks

Databases of genetic, clinical, environmental and lifestyle information on individuals, along with corresponding clinical specimens.

Biodiversity

The diversity of life. The term usually refers to the number of different species in a given area, but can also refer to genetic diversity. An important concept for ecologists.

Bioengineering

The use of engineering techniques to solve medical problems. An example would be the design and production of artificial limbs.

Biofuel

A substance produced from plant material that is used as a fuel. Examples include biodiesel and bioethanol. Biofuels are renewable sources of energy.

Biosignature

A sign that provides evidence of past or present life. This could be an element (such as carbon), a fossil, a molecular structure or biomarker, or a specific composition or compound that suggests a biological process is at work.

Biotechnology company

A smaller company researching new drugs, often using new technologies (often referred to as ‘biotech’).

Biotic

Living.

Bipedal

Using two legs (or limbs) to walk.

Bipolar disorder

A condition characterised by periods of elevated mood and periods of depression.

Blood–brain barrier

A semi-permeable membrane separating the blood and the cerebrospinal fluid of the brain.

BMI

Body mass index. A measure used to determine whether a person is underweight, normal weight, overweight or obese, calculated by dividing body mass (kg) by height squared (m2). Healthy BMI values range from 18.5 to 25 kg/m2.

Body fat

Body fat (or adipose tissue) is a mass of fat cells in a thick layer under the skin. There are two types of fat: essential fat, which is vital for the general functioning of the body, and storage fat, which is used to release energy. Excess storage fat is also used by hibernating and migrating animals.

Brown fat

A type of adipose (fat) tissue, also known as brown adipose tissue (BAT). It is made up of cells full of mitochondria and is metabolically active, unlike white fat. The brown colour comes from iron that is attached to proteins in the mitochondria. It develops before we are born, in specific regions of the body such as between our shoulder blades.