Biology 101

When Steve Rogers came out of the ice in the 21st century, a lot had changed. He learned what he needed to know in order to survive in modern-day New York City and to fight the alien invasions. Now that nothing seemed to be knocking at Earth's door to kill everyone, Steve decided to catch up on some other interesting advancements in human knowledge. Wanting to understand how his own body operated and how the Super-Serum had changed it all those years ago, he decided to learn biology. After convincing Bucky to take the class with him and with what Tony jokingly called a "Stark Scholarship", Steve and Bucky attended their first ever college class.

Now, a few weeks later, Steve and Bucky were cramming for their first exam which was on "the building blocks of life." Back in the 40s, people were sure that it was all about proteins, but apparently they overturned that idea only a decade after the war ended, turning to "nucleic acids" instead. Completely drowning in all the new information, the two men had begged Banner to tutor them. However, the session that was supposed to be only three people was gaining the attention of the other Avengers, entertained by Steve and Bucky's utter confusion.

"Okay, so..." Steve closed his eyes to try and make sense of the new information. "Half the stuff goes to one thing and half the stuff goes to the other thing. So, it's, like, cut in half?"

"I'm assuming that by 'stuff' you mean DNA and by 'things' you mean the daughter cells?" Bruce asked, as much confused by Steve's explanation as Steve was by the textbook's explanation.

"I still don't get why there can't be son cells," Bucky said, looking down at his textbook and shaking his head in pure disgust.

Peter snorted. He couldn't help it: these two grown men were learning about the building blocks of life for the first time while Peter had been hearing about it since middle school. He had found two people who graduated from high school and never once heard that the mitochondria was the powerhouse of the cell!

"Shut up, Parker! Not everyone is destined to cure cancer like you!" Bucky ordered, crumbling a page of his notes into a ball and chucking it at the teenager's head. But he found Peter's giggles contagious, and soon they were both laughing and throwing paper balls back and forth.

"Two points for the chest! Ten if you hit the head!" Natasha instigated.

"Hey, enough! Some of us actually care, okay?" Steve ran a hand through his hair. He could hardly wrap his head around the idea that a collection of little elements held all the secrets to life, and the professor was asking him to memorize how it was made? There were way too many proteins, and he couldn't visualize what an "antiparallel double helix" even looked like, let alone how it split apart!

"Why do you care so much, Captain? This book of life is limited to humans," Thor noted. "It doesn't even take into account the complex workings of the magical art‒"

"Forget the magical arts," Shuri interrupted. "It doesn't even include all the 'complex workings' of the human side of things. The textbook doesn't even cover the process in terms of energy transfer."

"Wait, what?" Peter's face scrunched up.

"Geez, finally something that you don't already know about this stuff," Bucky teased Peter.

"People, people! Please, we don't want this to take all day," Bruce said. When it was quiet again, he turned to Steve. "Back to your original question, it's not just cut in half. The currently-accepted semiconservative replication theory proposes that half the original strand goes to one copy and the other half goes to the other strand. The replication process begins with the enzyme helicase‒"

"So ‒sorry to interrupt‒ enzymes are proteins which are made from DNA?" Steve summarized, connecting the pieces of information.

"Yes, and doesn't that beg the question: what came first, the DNA or the proteins that made it?" Tony sauntered into the kitchen to grab a water bottle. A devilish grin spread across his face as chaos ensued: Peter sat back in his chair, mouth gaping; Bucky swore under his breath; and Steve practically screamed "Is she going to ask that on the exam?!" in fear.

"Trick question," Stephen Strange, having followed Tony into the kitchen, declared confidently. The others momentarily stopped laughing to listen. "Time is an illusion. There is no beginning as your question suggests," the doctor finished then proceeded to take Tony's water for himself.

"I can't take this anymore!" Bucky burst out. He slammed his hands down on the textbook in front of him, then pushed it hard into the nearest wall, making everyone jump. He was out the door before his pages of notes had fully settled on the kitchen floor.

"Me neither," Steve agreed, standing up. "I'm going to Sam's." Cleaning up slightly more elegantly than his best friend, Steve dumped his books and papers into his backpack before following Bucky out the door.

Silence followed, and the Avengers soon began dispersing, having lost their source entertainment.

"Pete, you good?" Tony asked, hesitating before leaving the kid alone in the kitchen.

The teen looked up at his mentor. "Mr. Stark, I still can't figure out what came first."