In the first level of DNA organization, eight histones come together to form a small spool, or bead, that winds a short segment of DNA. This spool, or bead, is called a ______.

Question

BlackTom AI · Accepted Answer

In this question, we’re asked to identify the term for the bead-like unit formed when eight histones come together to wind a short piece of DNA at the first level of DNA organization.
Option 1: 'nuclear bead' — This phrasing is not the standard term used in chromatin structure. The 'nuclear bead' might sound plausible, but the canonical term is different, and textbooks consistently use the term associated with histone-DNA complexes rather than a generic descriptor.
Option 2: 'histone' — Histones are the protein components around which DNA winds, but the histones themselves aggregate into a larger structure. Here, the word we want denotes the combined structure that includes histones and the DNA segment, not the protein itself.
Option 3: 'acetylation group' — An acetylation group refers to a chemical modification that can occur on histones influencing chromatin compaction and gene expression. It is not the name of the structural unit formed by histones and DNA.
Option 4: 'nucleosome' — This is the precise term for the repeating bead-like unit consisting of eight histone proteins around which ~146 base pairs of DNA are wrapped. It represents the fundamental level of chromatin organization and the canonical description matches the scenario given in the question.
Thus, evaluating all options, the correct concept is the nucleosome, while the other choices either refer to components, modifications, or nonstandard terminology that do not name the bead-like DNA–histone complex described. The distinction hinges on recognizing that a nucleosome is the specific structural unit formed by histone proteins and DNA at this level of packaging.

In the first level of DNA organization, eight histones come together to form a small spool, or bead, that winds a short segment of DNA. This spool, or bead, is called a ______.单项选择题

类似问题

You own a bond that pays $64 in interest annually. The face value is $1,000 and the current market price is $1,021.61. The bond matures in 11 years. What is the yield to maturity?

Which of the following statements is CORRECT?

It will cost $9,600 to acquire an ice cream cart that is expected to produce cash inflows of $3,600 a year for three years. After the three years, the cart is expected to be worthless. What is the payback period?

A 3.25 percent Treasury bond is quoted at a price of 99.04. The bond pays interest semiannually. What is the current yield?

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单