На конференции есть секция по биологии.

At the conference there is a section on biology.

Breakdown of На конференции есть секция по биологии.

• на: at
• по: on
• биология: the biology
• конференция: the conference
• секция: the section

Questions & Answers about На конференции есть секция по биологии.

Why is it на конференции and not в конференции?

Russian usually uses на with events and activities (conferences, concerts, exhibitions, lessons, meetings), because they are seen as occasions, not physical containers.

You normally say:

• на конференции – at the conference
• на уроке – in class / at the lesson
• на концерте – at the concert
• на выставке – at the exhibition

Using в конференции would sound wrong in this context. В is used more with physical spaces and enclosed locations (in a house, in a city, in a room).

Why does конференции end with -и? What case is that?

Конференции is the prepositional singular of конференция (a regular feminine noun in -я).

The declension is:

• nominative (subject): конференция – conference
• prepositional (location, after в, на): на конференции – at the conference

So на конференции literally means on/at the conference, and the ending -и is required by the prepositional case.

What is the function of есть here? Can I leave it out?

In this sentence, есть functions as there is / there exists.

• На конференции есть секция по биологии.
  Literally: At the conference there is a section on biology.

In modern Russian, есть in this existential meaning is often optional in the present tense, especially in short, simple sentences. You can say:

• На конференции есть секция по биологии.
• На конференции секция по биологии.

Both sound natural. Including есть sounds a bit more neutral and explicit; without есть it can sound slightly more matter‑of‑fact or spoken, but it is still standard.

What exactly does секция mean here?

In the context of a conference, секция is a section, track, or thematic session within the conference program.

It refers to a group of talks or presentations united by a particular topic. So секция по биологии is the biology section/track, i.e. the part of the conference devoted to biology.

It is not a physical partition of a room; it is more like an organizational category or program segment.

Why is it по биологии? What case is that, and why use по?

Биологии is in the dative case singular, governed by the preposition по.

По + dative often means on / about / in the field of when talking about topics, subjects, or areas:

• курс по биологии – a course in biology
• лекция по истории – a lecture on history
• доклад по физике – a report on physics

So секция по биологии literally means a section on biology. This is the most natural way to say it in Russian.

Could I say секция биологии instead of секция по биологии?

In theory, секция биологии is grammatically possible, but it is not the usual way to express this idea in standard Russian.

• секция по биологии – normal, idiomatic: a section dealing with biology
• секция биологии – sounds unusual, could be interpreted more as a section belonging to biology; in practice people do not say it this way for conference sections.

For subjects, fields, and topics, Russian strongly prefers по + dative: по биологии, по математике, по экономике, etc.

Can I say биологическая секция instead of секция по биологии? Is there a difference?

Yes, биологическая секция is possible, and it means essentially the same thing: biology section.

• секция по биологии – literally, a section on biology
• биологическая секция – literally, a biological section (section related to biology)

Both are acceptable. Секция по биологии is slightly more neutral and common in formal descriptions of programs. Биологическая секция sounds a bit more like a label or name: the Biology Section.

What word order variations are possible, and do they change the meaning?

These variants are all grammatically correct:

• На конференции есть секция по биологии. – neutral, most natural.
• На конференции секция по биологии. – without есть, still neutral/spoken.
• Есть секция по биологии на конференции. – focus slightly more on the existence of the section, and на конференции feels like additional information.
• Секция по биологии есть на конференции. – emphasizes that this particular section exists at the conference (for example, in contrast to other events).

The basic meaning remains there is a biology section at the conference, but Russian uses word order to shift emphasis rather than to mark grammatical roles.

Why doesn’t Russian just say something like Конференция имеет секцию по биологии to mean the conference has a biology section?

Russian can say Конференция имеет секцию по биологии, but it sounds unusually formal or bookish here.

For possession and existence, Russian usually prefers existential constructions with есть or just placing the location phrase first:

• На конференции есть секция по биологии. – At the conference there is a biology section.
• У конференции есть биологическая секция. – The conference has a biology section (also possible, but less natural than the first).

The pattern X имеет Y exists, but is more typical in official, technical, or very formal styles, and less natural for everyday descriptions like this.

Is естЬ the normal verb to be, and why is it visible here but usually missing in Russian?

Modern Russian has a special pattern:

• For equative sentences (X is Y) in the present tense, the verb to be is usually omitted:

  • Он врач. – He is a doctor. (no visible verb)

• For existential sentences (there is / there exists), есть is often used (though it can be omitted in informal style):

  • В городе есть парк. – There is a park in the city.

Your sentence is existential: it states that a certain thing exists at a certain place. So есть is natural here as there is, not as a simple copular is between two noun phrases.