n.核，原子核，细胞核，核心，中心

原形：nucleus复数：nuclei

The people is the nucleus of the country.
人民是国家的核心。
These young people formed the nucleus of the music.
这些年轻人成了这首歌的核心。
Truth is the nucleus of an effective team.
信任高效团队的核心。
The nucleus is the control center of the cell.
核心是细胞的控制中心。
In a eukaryotic cell, the DNA is contained within the nucleus.
在真核细胞中，DNA存在于细胞核内。
The nucleus of an atom is composed of protons and neutrons.
原子的核由质子和中子组成。
The nucleus of a city is usually its downtown area.
一个城市的中心通常是它的市中心。
The scientist studied the structure of the atomic nucleus in great detail.
这位科学家详细研究了原子核的结构。
The nucleus plays a crucial role in regulating gene expression.
核心在调节基因表达方面起着关键作用。
The nucleus pulposus is the central part of an intervertebral disc.
髓核是椎间盘的中央部分。
The command and control center was the nucleus of the operation.
指挥和控制中心是行动的核心。
In some cells, the nucleus can be seen under a microscope.
在一些细胞中，细胞核可以通过显微镜看到。
The nucleus of a cell contains genetic material in the form of chromosomes.
细胞核中含有以染色体形式存在的遗传物质。