Science Assessment ~ Ideas ~ There are similarities and differences between organisms living today, and between organisms living today and those that lived in the past, both within the same species and between species.

Key Idea: All living things contain genes made of DNA, and those genes code for proteins that are responsible for an organism's traits.

Sub-Ideas
Items & Student Performance
Misconceptions
NGSS

Students are expected to know that:

DNA is present in all organisms.
DNA is made of a 4-letter code: A, C, G, T.
A, C, T, G pair together in a specific and predictable way to form a DNA molecule.
Genes are made of DNA molecules.
Genes are responsible for both an organism's physical characteristics and the functions of its cells.
A core set of genes is required for basic life functions; these are common to all types/domains of organisms.
Genes code for proteins.
Cells make specific proteins by reading the genetic code in specific genes.
Proteins underlie the structure and function of all living things.
Proteins build and operate an organism, working at the molecular, cellular, tissue, and organismal level.
Proteins are made from amino acids, which are the building blocks of proteins.
Different combinations of amino acids make different proteins.
The sequence of amino acids in a protein determines its structure and function.
The arrangement of DNA building blocks in a gene specifies the types of amino acids and the order of amino acids in the protein it codes for.
Vastly different organisms make similar proteins.
All organisms make proteins the same way.
All cells in an organism contain the same genes, but not all of those genes are used (expressed) by every cell.
Organisms can decode the information in each other's genes to build identical proteins.

Percent of students answering correctly (click on the item ID number to view the item and additional data)
Item ID Number	Knowledge Being Assessed	Grades 6–8	Grades 9–12	Select This Item for My Item Bank
RH045001	DNA molecules are found in humans, dogs, and trees.	42%	54%
RH015002	The information in DNA molecules provides instructions for assembling amino acids into protein molecules.	24%	35%

Frequency of selecting a misconception
Misconception ID Number	Student Misconception	Grades 6–8	Grades 9–12
RHM105	There are some types of organisms that do not have DNA (See Lewis & Wood-Robinson, 2000; Banet & Ayuso, 2000).	58%	46%
RHM048	Only animals have DNA; plants and mushrooms do not have DNA (Banet & Ayuso, 2000).	43%	33%
RHM064	The information in DNA molecules provides instructions for rearranging genes into traits (AAAS Project 2061, n.d.).	41%	29%

Frequency of selecting a misconception was calculated by dividing the total number of times a misconception was chosen by the number of times it could have been chosen, averaged over the number of students answering the questions within this particular idea.

NGSS Statements
Code	Statement
LS1.C HS	The sugar molecules thus formed contain carbon, hydrogen, and oxygen: their hydrocarbon backbones are used to make amino acids and other carbon-based molecules that can be assembled into larger molecules (such as proteins or DNA), used for example to form new cells.
LS3.A MS	Genes are located in the chromosomes of cells, with each chromosome pair containing two variants of each of many distinct genes. Each distinct gene chiefly controls the production of specific proteins, which in turn affects the traits of the individual. Changes (mutations) to genes can result in changes to proteins, which can affect the structures and functions of the organism and thereby change traits.
LS1.A HS	All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.