English Corner 5: articles

The articles the, a and an are often omitted when needed, and used when they need not be. It should be easy to tell when they are required, for as their names imply, the definite article is used with definite (defined, particular, specific) items, whereas the indefinite article is used when the item referred to is used in an indefinite (general, vague) sense. However, the distinction between articles is not so straightforward, for no article (indicated here by the caret ^) is necessary, even when a specific process is referred to, if that word implies a specific process that on its own does need a definite article.

The cases below highlight how important the use, or lack, of an article can be in providing important information on meaning.

Use of the definite article only
• In [The PRDX6 gene was localised in the epithelium] a particular gene (PRDX6) and particular tissue (an epithelium) are referred to; in [The principal cell is the major cell of the epididymal epithelium], a particular cell type (principal, major) in a particular epithelium (in the epididymis), is referred to; in [The initial segment of the caput epididymidis], a particular region (the initial) of a particular part (the caput) of a particular organ (the epididymis) is referred to; in [The caput epididymidis is the first part of the epididymis], a particular part (the first) of a particular region (the caput) of a particular organ (the epididymis) is referred to.
• Similarly, when the reactions of specific subpopulations of experimentally-observed spermatozoa are to be described, the definite article is used [The acrosome-reacted spermatozoon penetrated the zona pellucida. The hyperactivated spermatozoon penetrated the cumulus oophorus. The capacitated spermatozoon underwent ^hyperactivation), because only the specific groups of spermatozoa (the acrosome-reacted, the capacitated, the hyperactivated) are being described, in contrast to the control groups of spermatozoa that are non acrosome-reacted, non-capacitated and non-hyperactivated, and that do not penetrate the zona or cumulus, or undergo hyperactivation.

Use of the indefinite article only
• In [An acrosome-reacted spermatozoon can penetrate the zona pellucida. A hyperactivated spermatozoon can penetrate the cumulus oophorus. A capacitated spermatozoon can undergo ^hyperactivation], the indefinite article is used for the types of spermatozoa, as the properties of acrosome-reacted, hyperactivated and capacitated cells are referred to in general, and no particular subpopulation of acrosome-reacted, capacitated or hyperactivated cells is described.

Differences in meaning with definite or indefinite articles
The use of the definite and indefinite article may depend on whether the noun referred to has appeared earlier in the text.
• In [Spermatozoa were adjusted to a concentration of 15x10₆/ml], the indefinite article is used, although a specific value is given, because the specificity resides in the value given. In [Spermatozoa were adjusted to the concentration of 15x10₆/ml], the definite article indicates that the specific value of 15x10₆ has previously been cited (perhaps to distinguish it from another concentration used in another procedure).
• In [Sperm concentration was measured in a Neubauer chamber], although a specific chamber is mentioned (the Neubauer rather than the Thoma chamber), the indefinite article is used since any Neubauer chamber, not a particular one, is meant. If a particular chamber is referred to (perhaps one that has been calibrated) one would write [Sperm concentration was measured in the Neubauer chamber], where the details of that particular chamber (as having been validated) have been referred to previously.

Differences in meaning with definite, indefinite or no articles
• In [β-catenin, a tumour promoter, is present in the epididymis], β-catenin is just one of many tumour promoters (not a specific one) referred to, whereas in [The tumour promoter b-catenin is upregulated in hypoxia] this specific protein, in contrast to others that are not upregulated, is referred to.
• In [It is useful for studying ^developmental biology], where developmental biology in general is meant, no article is used, whereas in [It is useful for studying the developmental biology of the testis] the definite article indicates that a specific biology (developmental) of a specific organ (the testis) is being described.
• No article is needed if the general subjects of the sentences are plural [^Acrosome-reacted spermatozoa can penetrate the zona pellucida. ^Hyperactivated spermatozoa can penetrate the cumulus oophorus. ^Capacitated spermatozoa can undergo hyperactivation].

No article with specific processes
Note in the sentences above that the zona pellucida and the cumulus oophorus need the definite article, since they refer to specific objects (thespecific zona that is pellucid (clear), and the specific cumulus that surrounds the oocyte) whereas ^hyperactivation takes no article. This is because, although the latter refers to a specific process, that specific process has a description that includes a definite article (the process of hyperactivation).
In other words [A capacitated spermatozoon can undergo ^hyperactivation] implies [A capacitated spermatozoon can undergo the hyperactivation process]. Similarly, [^Spermatozoa underwent ^capacitation] implies [^Spermatozoa underwent the capacitation process], so that the single word capacitation by itself requires no article. Writing [the capacitation] or [the hyperactivation] is incorrect because this means [the (the capacitation process)] and [the (the hyperactivation process)], where the definite article, though written only once, is implied twice.
By contrast, in [^Spermatozoa underwent the acrosome reaction], a particular reaction (one occurring to the acrosome) is referred to, so the definite article is needed. Thus, in contrast to ^capacitation and ^hyperactivation, there is no such global term for the acrosome reaction, which always requires the definite article.

No article with defined parameters

• The common semen parameters do not require the definite article: in [^Sperm concentration was assessed in a Neubauer chamber. ^Sperm motility was measured by CASA. ^Sperm viability was assessed by eosin-nigrosin staining. ^Sperm morphology was assessed after Shorr staining] it is the concentration, the motility, the viability or the morphology of spermatozoa that is, respectively, implied, and these phrases require the definite article. Similarly [The results are shown in ^Table 2 and in ^Figure 8] means that the results are to be found in specific places, namely, the 2^nd Table and the 8^th Figure.

Example
^Spermatozoa are produced in the testis and travel through the epididymis by the action of ^peritubular smooth muscles that are stimulated by the local network of ^peri-capsular nerves, which are part of the local autonomic nervous system. Upon ^ejaculation ^seminal fluid is transferred to the female tract where ^spermatozoa have to pass through ^cervical mucus by ^active motility and then through the uterus, which aids ^sperm passage by ^peristaltic contractions. In the oviduct ^spermatozoa undergo ^capacitation and display ^hyperactivated motility and the acrosome reaction. They are attracted to the ovulated oocyte by ^chemotaxis and ^thermotaxis. When ^spermatozoa reach the oocyte they have to penetrate the zona pellucida and then have to fuse with the oolemma.

Explanation
Spermatozoa (no definite article: all spermatozoa, not a definite subpopulation) are produced in the testis (definite article: a specific organ) and travel through the epididymis (definite article: a specific organ) by the action (definite article: a specific action) of peritubular smooth muscles (no definite article: the muscles are particular muscles [peritubular in location] but this is described by the adjective peritubular) that are stimulated by the local network (definite article: a specific network) of peri-capsular nerves (no definite article: the nerves are specific [peri-capsular in location] but this is described by the adjective peri-capsular), which are part of the local autonomic nervous system (definite article: a specific nervous system, autonomic not central). Upon ejaculation (no definite article: this is a specific process but it is short for the ejaculatory process) seminal fluid (no definite article: the fluid is a particular one [produced by the accessory glands] but this is described by the adjective seminal) is transferred to the female tract (definite article: a specific tract of the female) where spermatozoa (no definite article: all spermatozoa, not a definite subpopulation) have to pass through cervical mucus (no definite article: the mucus is a particular fluid [produced by the cervix] but this is described by the adjective cervical) by active motility (no definite article: the motility is specific [active not passive] but this is described by the adjective active) and then through the uterus (definite article: a specific organ), which aids sperm passage (no definite article: the passage is specific [that of the spermatozoa] but this is described by the adjectivesperm) by peristaltic contractions (no definite article: the contractions are specific [peristaltic in nature] but this is described by the adjective peristaltic). In the oviduct (definite article: a specific organ) spermatozoa (no definite article: all spermatozoa, not a definite subpopulation) undergo capacitation (no definite article: this is a specific process but it is short for the capacitation process) and display hyperactivated motility (no definite article: this is a specific process but it is short for the hyperactivation process) and the acrosome reaction (definite article: a specific reaction of the acrosome). They are attracted to the ovulated oocyte (definite article: a specific oocyte, ovulated not follicular) by chemotaxis (no definite article: this is a specific process but it is short for the chemotaxis process) and thermotaxis (no definite article: this is a specific process but it is short for the thermotaxis process). When spermatozoa (no definite article: all spermatozoa, not a definite subpopulation) reach the oocyte (definite article: a specific cell type) they have to penetrate the zona pellucida (definite article: a specific egg structure) and then have to fuse with the oolemma (definite article: a specific egg membrane).

By Dr Trevor G Cooper (ctrevorg@gmail.com)