Platelets and Blood Components:

[5words]

Question from the TPR:

Platelets do not normally aggregate in the absence of tissue injury because:
I. platelets are not normally found in plasma.
II. they are not exposed to compounds present in
damaged cells.
III. circulating T cells prevent aggregation.

A. I only
B. II only
C. I and II only
D. I, II, and III


So i chose C but the answer is B and their explanation is that the platelets are always found in the plasma... Is this a mistake? because blood only has 3 component = Plasma , Buffy coat and The erythorcytes... The plasma includes the protiens, electrolytes as well as water , whereas the buffy coat contain The platelets and WBC.

So is this a mistake? because i cant find website online which list the plats as a Plasma component.

Thanks

---

Members don't see this ad.

 

[twist2]

Platelets are present in the plasma. A low platelet count in the plasma is known as thrombocytopenia.

 

[5words]

Platelets are present in the plasma. A low platelet count in the plasma is known as thrombocytopenia.

Just googled it, and its say low Platelet count in *blood* and not plasma.. I seriosuly want to get this over with, do you have an article or something which said that Platelet can be found in the plasma, even how the diagnosis is made? Like do the centrifuge the blood first, get rid of the pellet and analyze the supernatant ? If this was true, i'd be hard to conclusively say that platelets are found in the plasma since they are less dense than erythrocytes and more dense than the plasma, so they are usually located in between!

Three layers of blood - plasma (mostly water, 7% proteins and electrolytes) .. Buffy coat( platelets and WBC) and RBC.

Please help understand this!

 

[twist2]

I see what you are saying. First, technically they are present in plasma because the cells are suspended in the plasma if they aren't spun down in a tube. Second, I is not an answer to the question because it is not the reason WHY platelets do not aggregate in the absence of injury. II is the reason why the platelets do not aggregate. I think you are overthinking this question, which is easy to do.

 

[5words]

I see what you are saying. First, technically they are present in plasma because the cells are suspended in the plasma if they aren't spun down in a tube. Second, I is not an answer to the question because it is not the reason WHY platelets do not aggregate in the absence of injury. II is the reason why the platelets do not aggregate. I think you are overthinking this question, which is easy to do.

i like what you said there..