Transcript chromosomes
Chromosomes, DNA, and Genes EQ: Can I describe the relationship among genes, chromosomes, and inherited traits? 0707.4.3 What is a chromosome? • One of the structures in the nucleus that is made up of DNA and protein • Carries hereditary information in the form of genes • Humans have 23 pairs of chromosomes, 46 total. • You received 23 chromosomes from your father, and the other 23 chromosomes from your mother. CHROMOSOMES Sex Chromosomes • 22 of our pairs of chromosomes appear identical, but the other two chromosomes are called sex chromosomes- X and Y. • Females= 2 X Chromosomes • Males= 1 X and 1 Y Chromosome What is DNA? • A molecule that is present in all living cells and that contains the information that determines traits that a living thing inherits and needs to live. DNA Each cell in your body contains about 6 feet of DNA thread, for a total of about 3 billion miles of DNA inside you! What is a Gene? A gene is one set of instructions for an inherited trait. • Each cell in the human body contains about 25,000 to 35,000 genes GENES Genes are found on chromosomes- there can be hundreds or even thousands of genes on a single chromosome. Genes determine physical traits, such as the color of your eyes, the color of your hair, and your height. GENES Genes can be DOMINANT or RECESSIVE. • Dominant genes are passed down even if there is only one copy of that gene in the pair. • For a recessive gene to be passed down, the person must have that gene on both chromosomes of the pair. DOMINANT TRAIT RECESSIVE TRAIT BROWN EYES HAZEL EYES DARK HAIR BLUE EYES CURLY HAIR BLONDE HAIR FRECKLES STRAIGHT HAIR Study Jams- Heredity