How do traits relate to protein

But, how does the nucleus know so much? It contains our chromosomes and genes. As tiny as it is, the nucleus has more information in it than the biggest dictionary you've ever seen.

In humans, a cell nucleus contains 46 individual chromosomes or 23 pairs of chromosomes chromosomes come in pairs, remember? Half of these chromosomes come from one parent and half come from the other parent. Under the microscope, we can see that chromosomes come in different lengths and striping patterns. When they are lined up by size and similar striping pattern, the first twenty two of the pairs these are called autosomes; the final pair of chromosomes are called sex chromosomes, X and Y.

The sex chromosomes determine whether you're a boy or a girl: females have two X chromosomes while males have one X and one Y. But not every living thing has 46 chromosomes inside of its cells.

For instance, a fruit fly cell only has four chromosomes! Each gene has a special job to do. The DNA in a gene spells out specific instructions—much like in a cookbook recipe — for making proteins say: PRO-teens in the cell.

Proteins are the building blocks for everything in your body. Bones and teeth, hair and earlobes, muscles and blood, are all made up of proteins. Those proteins help our bodies grow, work properly, and stay healthy. Scientists today estimate that each gene in the body may make as many as 10 different proteins.

That's more than , proteins! Like chromosomes, genes also come in pairs. Each of your parents has two copies of each of their genes, and each parent passes along just one copy to make up the genes you have. Genes that are passed on to you determine many of your traits, such as your hair color and skin color. Maybe Emma's mother has one gene for brown hair and one for red hair, and she passed the red hair gene on to Emma. If her father has two genes for red hair, that could explain her red hair.

Emma ended up with two genes for red hair, one from each of her parents. You also can see genes at work if you think about all the many different breeds of dogs. See Subscription Options. Go Paperless with Digital. Stuart E. Ravnik, assistant professor of cell biology and biochemistry at the Texas Tech University Health Sciences Center, summarizes the answer to this seemingly simple question: Image: Nikolaj Blom and Michael Lappe.

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For example, some amino acids attract water, and others are repelled by it. Some amino acids can form weak bonds to each other, but others cannot. Different combinations and sequences of these chemical characteristics determine the unique three-dimensional folded shape of each protein. The structure of a protein determines its function.

Proteins that catalyze accelerate chemical reactions, for example, have "pockets," which can bind specific chemicals and make it easier for a particular reaction to occur.

Variations in the DNA code of a gene can change either the structure of a protein or when and where it is produced. If these variations change the protein structure, they could also change its function.

For example, a single, specific mutation in hemoglobin -- the oxygen-carrying protein abundant in your red blood cells -- affects oxygen transport and is enough to cause sickle-cell anemia. Variations in a gene can affect traits in several ways. Variations in proteins involved in growth and development, for example, can give rise to differences in physical features like height.