Compounds: Science

Compound adjective phrases

It is rare to find more than two or three adjectives placed in sequence together in everyday speech. There is a standard word order for multiple adjectives: opinion, size, age, shape, colour, origin, material.

These phrases occur more frequently in technical and scientific language and they are frequently very close in meaning and category and so less easy to order according to the rule above (e.g. Pure aluminium is a light, nontoxic, nonmagnetic and non-sparking, silvery-white metal. It is reflective, malleable, easily machined and cast, and is soft, weak and decorative.). As a general rule, the adjective which is closest to the related noun in meaning comes first. It is usually describing a permanent characteristic, while other more variable characteristics come last.

using multiple adjectives

- Enzymes are complex three-dimensional globular proteins which speed up the organism’s metabolism without being changed by the reaction.

adding a noun phrase to a present participle (-ing) with a hyphen

energy-demanding: People who lead sedentary lives may take up some form of sport or energy-demanding activity to boost their energy use.
oxygen-carrying: This results in an increase in the number of red blood cells and the oxygen-carrying capacity of the blood.

adding the adverb well to a past participle (-ed)

Note: This usually refers to something that has been done or carried out in the past.

well-established: In the budding process a dormant bud is removed from one plant and attached so that it will grow on another plant that has a well-established root system.
well-labelled: The safe chemistry lab should have well-labelled chemical storage bottles that have secured caps.

adding to an adjective

adjective + noun: There is a much higher risk for a teenage mother of giving birth to a low-weight baby.
noun + adjective: A brick-red precipitate indicates the presence of a reducing sugar.
adjective + adjective: The ventricles contract, forcing atrioventricular valves to close and blood passes into arteries. ⁽¹⁾

linking a number phrase with a noun phrase (single-, five-)

single-celled: Yeast is a single-celled fungus reproducing asexually, by a process known as budding.
double-walled: It is a double-walled glass vessel: a small bottle inside a large one that only touches or joins at the mouth.
five-minute: At five-minute intervals for a total of 60 minutes, use a ruler to measure the distance moved by the solution from the original mark.

linking a past participle to a preposition with a hyphen

built-in: Some plants have a built-in mechanism allowing seeds to be scattered when the dry fruit suddenly bursts open.

Compound noun phrases

Nouns are modified using other words such as adjectives, other nouns or present (-ing) or past (-ed) participles. Modifying nouns function in a similar way to adjectives, and they are created with new ideas, as new needs arise for new terms.

These nouns can be standalone items, connected with a hyphen or compounded into one word.

nouns linked to other word forms by a hyphen

noun + noun
cross-pollination: Cross-pollination produces a greater variety of offspring because two parents are involved.
liquid-in-glass: The liquid used in a liquid-in-glass thermometer is usually either alcohol or mercury.
cross-section: A tooth cross-section shows that the tooth consists of three layers.

noun + past participle
insect-pollinated: Flowers such as roses and dandelions are mainly insect- or animal-pollinated.
air-borne: Some flowers have feathery stigmas to catch air-borne pollen grains.
enzyme-catalyzed: Because less Ea is need in an enzyme-catalyzed reaction, reactions will occur more frequently and more rapidly.

noun + adjective
water-soluble: Water-soluble vitamins are easily assimilated by the body because they dissolve in water and mix easily with the blood.
fat-soluble: Fat-soluble products and vitamins are absorbed into the lacteal and transported to the liver.

several ideas compounded into a one-word phrase

backbone: All fatty acids are lipids and have a long hydrocarbon chain forming a pleated backbone of carbon atoms with hydrogen atoms attached, and a carboxyl (COOH) group at one end.
photosynthesis: The cotyledons get into the light quickly and have chlorophyll for photosynthesis so they can make food. ⁽²⁾

standalone items in multiple mixed-word strings

multiple noun strings
- Explain the difference between systolic and diastolic blood pressure measurement readings. ⁽³⁾
- Living organisms have special waste produce excretion mechanisms that result in excretion of by-products from the body.
- Glycogen is the only carbohydrate energy store found in animals.
- The resistance of negative temperature coefficient thermistors decreases as the temperature increases.

mixed strings – noun, adverb, participle, adjective
- There are about twenty commonly occurring amino acids in protein.

adjective and noun strings
- The cell nucleus is found in all eukaryotic cells except red blood cells and mature phloem sieve tubes.

Notes

There are other compound forms which are dealt with in Comparisons: Science and include phrases such as -like, -shaped, etc.)

^{(1) (2)} There are many compound phrases like these in science – too many to cover here! They can be studied in a similar way as prefixes, infixes and suffixes, which are dealt with in other sections of onestopenglish, e.g. Comparisons: Science and Grammar: affixes)

 ⁽³⁾ It is very common to find multiple word strings used in science to describe devices, machines and instruments.