Question

Platelets in birds and reptiles: a. Lack cytoplasm b. Have nuclei and are called thrombocytes c. Lack nuclei d. Have prominent central zone of pallor

1) Lack cytoplasm
2) Have nuclei and are called thrombocytes
3) Lack nuclei
4) Have prominent central zone of pallor

Answer 1

Bird and reptile platelets, known as thrombocytes, contain nuclei, unlike mammalian platelets which are anucleate. This is a distinctive feature of the blood cells in these classes of vertebrates.

Step-by-step explanation:

In birds and reptiles, the cellular elements playing a role equivalent to mammalian platelets are actually called thrombocytes. Unlike mammalian platelets, which lack a nucleus, these thrombocytes do have nuclei. Therefore, the correct answer to the student's question is that bird and reptile platelets have nuclei and are called thrombocytes.

When comparing other vertebrate red blood cells to mammalian red blood cells, it's found that other vertebrates typically have nucleated red blood cells. These are also capable of replication and have a relatively short lifespan; whereas mammalian red blood cells are anucleate and have a longer lifespan in the bloodstream.