No novo setor, cada profissional precisa ser responsável e eficiente.

No is a contraction of em + o:

• em = in / on / at
• o = the (masculine singular)

So:

• no novo setor = in the new sector/department

This is extremely common in Portuguese:

• no = em + o
• na = em + a
• nos = em + os
• nas = em + as

Example:

• na empresa = in the company
• nos setores = in the sectors

Both are possible, but adjective position in Portuguese can slightly affect style or nuance.

• novo setor usually means new department/sector
• setor novo can also mean new sector, but may sound a little more descriptive or contrastive depending on context

In many cases, before the noun sounds a bit more fixed or natural with common adjectives like novo, while after the noun can feel more literal or emphatic.

So no novo setor is a very natural way to say in the new department/sector.

The comma separates an introductory phrase from the main clause.

• No novo setor sets the scene: In the new department
• Then the main statement comes: cada profissional precisa ser responsável e eficiente

This is similar to English:

• In the new department, each professional needs to be responsible and efficient.

The comma is helpful and natural, though in some short sentences Portuguese punctuation can be somewhat flexible.

Cada profissional means each professional / every professional. It focuses on individuals one by one.

• cada profissional = each individual professional
• todos os profissionais = all the professionals

Both are possible, but they are not exactly the same in tone:

• Cada profissional precisa... = each person has this obligation
• Todos os profissionais precisam... = all of them, as a group, have this obligation

Portuguese often uses cada + singular noun just like English uses each/every + singular noun.

Because cada is followed by a singular noun in Portuguese.

So you say:

• cada profissional
• cada pessoa
• cada aluno

Not:

• cada profissionais ❌

This works like English:

• each professional
• each student

Even though the meaning refers to many people, the grammar stays singular after cada.

Because the subject is grammatically singular:

• cada profissional = singular

So the verb must also be singular:

• cada profissional precisa

Not:

• cada profissional precisam ❌

This is the same logic as in English:

• Each professional needs... not
• Each professional need... ❌

If the subject were plural, then the verb would be plural:

• Todos os profissionais precisam ser responsáveis e eficientes.

Precisa ser means needs to be or must be, depending on context.

• precisa comes from precisar
• ser = to be

So:

• cada profissional precisa ser responsável e eficiente = each professional needs to be responsible and efficient

In many workplace or formal contexts, this can sound close to must be in English, even though the literal structure is needs to be.

Portuguese uses ser for more essential, defining, or expected qualities, and estar for temporary states or conditions.

Here, responsável and eficiente are presented as qualities a professional should have in general, so ser is the natural choice:

• ser responsável
• ser eficiente

If you used estar, it would suggest a temporary condition:

• estar responsável is generally not natural in this meaning
• estar eficiente would sound unusual for this sentence

So ser is correct because the sentence talks about professional qualities, not momentary states.

Because after ser, adjectives usually appear directly, without an article.

So you say:

• ser responsável
• ser eficiente
• ser honesto
• ser cuidadoso

Not usually:

• ser um responsável ❌
• ser um eficiente ❌

In this sentence, responsável and eficiente are predicate adjectives describing cada profissional.

Yes, they can change for number, but in the singular they are the same for masculine and feminine.

Here:

• responsável = masculine singular or feminine singular
• eficiente = masculine singular or feminine singular

Plural forms:

• responsáveis
• eficientes

Examples:

• O profissional é responsável e eficiente.
• A profissional é responsável e eficiente.
• Os profissionais são responsáveis e eficientes.
• As profissionais são responsáveis e eficientes.

So in your sentence, the adjectives stay singular because cada profissional is singular.

Setor often means sector, but in workplace contexts it very commonly means department, section, or area.

So no novo setor could mean:

• in the new department
• in the new section
• in the new area

The best English translation depends on context. In a company, department is often the most natural choice.

Yes. A very natural alternative would be:

• No novo setor, todos os profissionais precisam ser responsáveis e eficientes.

This means In the new department, all professionals need to be responsible and efficient.

The difference is:

• cada profissional = highlights each individual
• todos os profissionais = highlights the whole group

Both are correct.

Here, profissional is a noun, meaning professional or worker/specialist, depending on context.

• cada profissional = each professional

But profissional can also be an adjective in other sentences:

• comportamento profissional = professional behavior
• atitude profissional = professional attitude

So the word can function in both ways, but in this sentence it is clearly a noun.