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Course: Middle school biology - NGSS > Unit 7
Lesson 2: Genes, proteins, and traitsGenes, proteins, and traits
Review your understanding of genes, proteins, and traits in this free article aligned to NGSS standards.
Key points:
- Genes are specific stretches of a chromosome’s DNA molecule. DNA molecules are made up of smaller parts called nucleotides. So, a gene is a specific stretch of nucleotides within a chromosome’s DNA.
- DNA is made up of four types of nucleotides. These nucleotides are often called by their shortened names: A, C, T, and G (which stand for adenine, cytosine, thymine, and guanine). The nucleotides in a gene are connected in a specific order.
- Proteins are molecules that carry out many different functions in cells. For example, some proteins provide structure for the cell. Others help carry out chemical reactions.
- Proteins are made up of smaller parts called amino acids. The amino acids in a protein are also connected in a specific order. A protein’s amino acids determine its 3D structure and its function.
- The cell builds proteins using instructions found in genes. Specifically, the order of nucleotides in a gene determines the order of amino acids in one or more proteins.
- An organism has many different genes, and so can produce many different proteins. These proteins have functions that affect the organism’s traits.
Want to join the conversation?
what is amino acids?(13 votes)
An amino acid (this wasn't really explained in the video) is a type of organic (carbon-based) compound containing both an amine (nitrogen) group and an acid group. Every three nucleotides (A,G,T, or C) stand for one amino acid, and the amino acid is determined by the nucleotide order. The amino acids then get linked together to make a protein as the DNA is decoded. Hope this helps!(15 votes)
How many types of protein can there be?(12 votes)
there can be about 10,000 different proteins.(10 votes)
- y is there cells in grass :/(7 votes)
- because the grass is a living thing. and cells are what make life possible.(19 votes)
- what are amino acids(6 votes)
- An amino acid (this wasn't really explained in the video) is a type of organic (carbon-based) compound containing both an amine (nitrogen) group and an acid group. Every three nucleotides (A,G,T, or C) stand for one amino acid, and the amino acid is determined by the nucleotide order. The amino acids then get linked together to make a protein as the DNA is decoded. Hope this helps!(3 votes)
How many genes are in a human(6 votes)- An international research effort called the Human Genome Project, which worked to determine the sequence of the human genome and identify the genes that it contains, estimated that humans have between 20,000 and 25,000 genes.(3 votes)
Are amino acids tiny proteins?(5 votes)
Amino acids are small molecules that are the building blocks of proteins. Proteins serve as structural support inside the cell and they perform many vital chemical reactions. Each protein is a molecule made up of different combinations of 20 types of smaller, simpler amino acids. Hope this helps.(2 votes)
- how big are genes(3 votes)
The diameter of the DNA double helix would be about 2.5 nanometers long, and all of our DNA stretched out would be about 10 billion miles long.(4 votes)
- HI, What are Amino Acids? Please answer I need help. Thanks(4 votes)
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups.(2 votes)
- what is protein(2 votes)
A protein is a chain of amino acids that has a specific function, and the order and types of amino acids in the protein, which influences the shape, structure, and function of the protein, is determined by particular genes.(1 vote)
What are Amino Acids?(2 votes)
Amino acids are molecules that are combined to form proteins. Basically when proteins are broken down/digested the amino acids still remain, it's used by the body to create proteins and to break down food.(5 votes)