An antigen is something that can produce an immune response...can come from any of the above.
Usually if they have chloroplasts, they’re autotrophic. If they don’t have chloroplasts then they’re autotrophic, although members of Excavata like euglenozoans can be mixotrophic
The cardiac muscle is only in the heart because it has special characteristics such as being able to make sustained contractions, coordinated movement, and rapid conduction. Hope this helps!
Answer:
Thioredoxin
Explanation:
Ribonucleotides serve as precursors for synthesis of deoxyribonucleotides and the reaction is catalyzed by enzyme ribonucleotide reductase. The reduction of a ribonucleotide into deoxyribonucleotide requires a pair of hydrogen atoms.
These hydrogen atoms are supplied from NADPH via ubiquitous protein thioredoxin. The oxidized form of thioredoxin is reduced back in a reaction catalyzed by thioredoxin reductase.