Please help Is there such thing as a QRS wave?

If so, what is the difference between QRS wave and QRS complex?

Which of the following are examples of coordinate headings

Group of genes that encode molecules found in all body cells, creating a biochemical “fingerprint” that serves as the “id” for cells so that they are marked as “self” a) deoxyribonucleic acid (dna) b) entry inhibitors c) major histocompatibility complex (mhc) d) non-nucleoside reverse transcription inhibitors (nnrtis)

When comparing the digestive and urinary system, we can conclude that they both