HOW ARE TRAITS PASSED ON FROM ONE GENERATION TO THE NEXT?
How are the characteristics of one generation related to the previous generation?
In all organisms the genetic instructions for forming species’ characteristics are carried in the chromosomes. Each chromosome consists of a single very long DNA molecule, and each gene on the chromosome is a particular segment of that DNA. The instructions for forming species’ characteristics are carried in DNA. All cells in an organism have the same genetic content, but the genes used (expressed) by the cell may be regulated in different ways. Not all DNA codes for a protein; some segments of DNA are involved in regulatory or structural functions, and some have no as-yet known function.
Topic Summary:
In all organisms, the genetic instructions for forming species’ characteristics are carried in the chromosomes. Each chromosome consists of a single very long DNA molecule, and each gene on the chromosome is a particular segment of that DNA. DNA molecules contain four different kinds of building blocks, called nucleotides, linked together in a sequential chain. The sequence of nucleotides spells out the information in a gene. Before a cell divides, the DNA sequence of its chromosomes is replicated and each daughter cell receives a copy. DNA controls the expression of proteins by being transcribed into a “messenger” RNA, which is translated in turn by the cellular machinery into a protein. In effect, proteins build an organism’s identifiable traits. When organisms reproduce, genetic information is transferred to their offspring, with half coming from each parent in sexual reproduction. Inheritance is the key factor causing the similarity among individuals in a species population.
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National Research Council 2012. A Framework for K-12 Science Education: Practices, Crosscutting Concepts, and Core Ideas. Washington, DC: The National Academies Press. https://doi.org/10.17226/13165
This site contains original content that may not be authorized for use by the creator and is legally used under the fair use principles section 107 of the Copyright Act of 1986 (17 U.S. Code § 107)
The official NGSS website. https://www.nextgenscience.org
LS3.A, HS-LS3-1
Ask questions to clarify relationships about the role of DNA and chromosomes in coding the instructions for characteristic traits passed from parents to offspring. (Cause and Effect) [HS-LS3-1]
This site contains original content that may not be authorized for use by the creator and is legally used under the fair use principles section 107 of the Copyright Act of 1986 (17 U.S. Code § 107)
The official NGSS website. https://www.nextgenscience.org
LS3.A, HS-LS3-1
Ask questions to clarify relationships about the role of DNA and chromosomes in coding the instructions for characteristic traits passed from parents to offspring. (Cause and Effect) [HS-LS3-1]