Ang uri ng dugo ay nasa sertipikong medikal.

No. Ay is not the Filipino verb for is.

In sentences like this, Filipino often has no separate present-tense copula. Instead, ay is a linker used in a more formal or inverted sentence pattern, separating the topic from what is being said about it.

So:

• Ang uri ng dugo ay nasa sertipikong medikal.
• Nasa sertipikong medikal ang uri ng dugo.

These mean the same thing, but the second one is more natural in everyday speech.

Ang marks the topic of the sentence: uri ng dugo.

So in:

• Ang uri ng dugo = the topic, blood type
• nasa sertipikong medikal = what is being said about it

English speakers often want to translate ang directly as the, and that is sometimes helpful, but it is better to think of ang as a marker for the main noun phrase rather than as a perfect equivalent of the English article.

Because uri means type or kind, and ng dugo means of blood.

So the structure is:

• uri = type
• ng = of
• dugo = blood

Literally, uri ng dugo is type of blood.

This is a very common Filipino pattern:

• pangalan ng tao = name of a person
• kulay ng kotse = color of the car
• uri ng dugo = type of blood

Here, ng connects uri and dugo and gives the meaning of.

So:

• uri ng dugo = type of blood

This ng is not the same as nang. Learners often mix those up, but in this sentence you just need to know that ng links the two nouns.

Nasa is a location word meaning something like is in, is on, or is at, depending on context.

In this sentence, it tells you where the blood type is located:

• nasa sertipikong medikal = on/in the medical certificate

A good learner-friendly way to understand it is:

• nasa + place = located in/on/at that place

Because sa by itself is usually just the location marker in/on/at/to, while nasa works naturally as the predicate of location.

Compare the idea:

• sa sertipikong medikal = in/on the medical certificate
• nasa sertipikong medikal = is in/on the medical certificate

So in this sentence, nasa is the normal choice because the sentence is saying where something is.

That -ng is a linker. Filipino often uses a linker to connect a noun with the word modifying it.

Here:

• sertipiko
  • -ng
    • medikal
      = sertipikong medikal

Because sertipiko ends in a vowel, the linker attaches as -ng.

This is very common:

• bahay na malaki = house that is big / big house
• librong bago = new book
• sertipikong medikal = medical certificate

Yes, that is grammatically possible.

Both of these can mean medical certificate:

• sertipikong medikal
• medikal na sertipiko

However, sertipikong medikal is a very common set phrase in official or administrative Filipino, so it sounds especially natural in this context.

Yes, it sounds a bit formal or written because of the ay structure.

In everyday spoken Filipino, many people would more naturally say:

• Nasa sertipikong medikal ang uri ng dugo.

That version is less formal but means the same thing.

Yes. Filipino can make complete sentences without a verb like English is/are.

This sentence is a nonverbal sentence with a locative predicate:

• Ang uri ng dugo = the topic
• nasa sertipikong medikal = the location being stated about it

So even though English needs is, Filipino does not need a separate verb here.

Usually that is the best translation here, yes.

But grammatically, ang is not exactly the same as English the. It marks a specific/topic noun phrase, and the exact feel of definiteness depends on context.

So the blood type is the most natural English translation here, but it is better not to assume that ang always equals the in every sentence.