nucleus

• 指事物、运动或群体中最核心、最重要的部分，是其活动与发展的基础。在生物学中指细胞中含有遗传物质的致密细胞器；在物理学中指原子带正电的中心；在天文学中指彗星的固体核心；在解剖学中指神经细胞的聚集；在日常用语中指一小群不可或缺的人或事物。

A noun referring to the central and most important part of an object, movement, or group, forming the basis for its activity and growth. In biology, it is the dense organelle in a cell containing genetic material; in physics, it is the positively charged core of an atom; in astronomy, it is the solid central part of a comet; in anatomy, it is a mass of nerve cells; and in general use, it denotes a small, indispensable group of people or things.

不规则复数

1. Cell nucleusB2formalscientific

   A membrane-bound organelle within a cell that contains the genetic material (DNA and RNA) and controls growth and reproduction.

   细胞核

   • The nucleus directs all cellular activities by regulating gene expression.
   • Scientists extracted the nucleus from the cell for further analysis.
   • The nucleus is often called the control center of the cell.

   同义词karyon

2. Atomic nucleusB2formalscientific

   The small, dense, positively charged central core of an atom, composed of protons and neutrons.

   原子核

   • The atomic nucleus contains nearly all the mass of the atom.
   • Nuclear fission involves splitting the nucleus of an atom.
   • Electrons orbit around the nucleus at various energy levels.

3. Core groupB2formal

   A small, essential group of people or things that form the central part of something larger.

   核心

   • A nucleus of experienced staff remained after the reorganization.
   • The club's nucleus consists of five founding members.
   • The project's nucleus is a team of dedicated volunteers.

   同义词centercoreessencefocushearthubkernelnub

4. Comet nucleusC1formalscientific

   The solid, central part of a comet's head, composed of ice, dust, and frozen gases, which vaporizes near the sun to form the coma and tail.

   彗核

   • The comet's nucleus is only a few kilometers in diameter.
   • As the comet approaches the sun, its nucleus heats up and releases gas.
   • Space probes have captured images of a comet's nucleus.

   同义词core

5. Neural nucleusC1formalmedical

   A distinct cluster of nerve cell bodies within the brain or spinal cord, identifiable by histology.

   神经核

   • The thalamus contains several important neural nuclei.
   • Damage to a specific neural nucleus can affect motor control.
   • The brainstem has nuclei that regulate vital functions.

6. Lens nucleusC1formalmedical

   The central, densest part of the eye's lens, surrounded by the lens cortex.

   晶状体核

   • Cataracts often form in the nucleus of the lens.
   • The lens nucleus becomes harder with age.
   • Surgery may involve removing the cloudy lens nucleus.