章 46: 044 Mysterious Vest

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"…"

The class fell silent again.

Xiu Yu almost cut his own eyebrow, steadied himself, and said, "Daddy Ying, you're not joking, right?"

Their Daddy Ying, wasn't he a complete dunce at school?

Ying Zijin stood up, her tone casual but serious, "No."

"Your book looks even newer than mine."

"Just finished reading it."

Xiu Yu: "..."

True to form, Daddy Ying.

While the whole class was still confused, the girl picked up her book and slowly made her way to the podium.

She rolled up her uniform sleeves and reached for a piece of chalk.

"Let's start with genetic engineering," Ying Zijin turned around and drew a circle on the blackboard, "This is a circular DNA, this DNA has one to several cutting sites, which can be opened with restriction endonucleases."

"There are generally three classes of restriction enzymes." As she spoke, she wrote down the key points with chalk, "The book only gives us two types, let's distinguish them now..."