lymphocytes are specialized T cell ,B cell, and natural killer cell .
these cells are distinguished from other lymphocytes by a protein on their surface known as the B cell receptor .these protein is specialized to recognize and attach to specific antigens.
DNA and RNA each contain four nitrogenous bases. They have 5 not 4.
Answer:
Toxic chemicals is a major cause of water pollution. In most cases, the toxic chemicals came from the residual from production process after companies done making their product
Explanation:
Answer:
The correct answer is B.
Explanation:
Option A is wrong. Mammals were not the prominent species before the extinction of dinosaurs because the mammal species that lived during the dinosaurs' era were so small that they only weighed several grams and occupied small areas as their habitats.
Option C is wrong. As dinosaurs became extinct, reptiles and "birds" remained as their descendant which evolved to some of the species that we know today.
Option D is wrong. Pangea started to break up to form the geographic isolation for the diversion of many species around 175 million years ago.
So the correct answer is B. Massive extinction disrupts and changes the food chain in such a big way that it triggers a domino effect that leads to species adapting to their new environment and diversifying thus forming new species in the process.
I hope this answer helps.
