What is a gene?
A. A point that joins halves of chromosome
B. A section of DNA that encodes a specific protein.
C. A large molecule that performs a specific function.
D. A structure that contains many chromosomes.
B. A section of DNA that encodes a specific protein.
B. A section of DNA that encodes a specific protein.
The correct answer is B. A gene is a section of DNA that encodes a specific protein.
To understand why this is the correct answer, let's break it down:
A. A point that joins halves of the chromosome: This refers to the centromere, which is a point that joins the two halves, or sister chromatids, of a chromosome during cell division. It is not the definition of a gene.
B. A section of DNA that encodes a specific protein: This is the correct definition of a gene. Genes are specific sequences of DNA that contain the instructions for building proteins. Proteins are the building blocks for various structures and perform many functions in living organisms.
C. A large molecule that performs a specific function: This answer is too broad. While DNA is a large molecule, genes are specific sections of DNA with a particular function (encoding proteins).
D. A structure that contains many chromosomes: This answer describes the nucleus of a cell, which contains multiple chromosomes. It does not define a gene.
Overall, option B is the best answer because it accurately describes a gene as a section of DNA that encodes a specific protein.