Final Answer:
Chromosomes — consist of an organized package of DNA and some protein found in the nucleus of a cell
Genes (or gene) — the chemical substance found in chromosomes that controls the traits inherited by organisms
DNA exists as a spiral twisted structure called an double helix
DNA can be copied or replicated. This allows the genetics of an organism to be passed to other cells it creates or to its offspring.
Each chromosome is made of protein and a DNA molecule.
Chromosomes are visible under the microscope under the microscope unless a cell is dividing.
Most of organisms have two sets of chromosomes.
Humans normally have 46 of chromosomes.
Our first 22 pairs of chromosomes are called autosomes. These have little role in determining our gender, but do carry the genetic code for body traits.
The 23rd pair in humans are the sex chromosomes. These play a major role in determining gender.
Individuals with two large sex chromosomes are XX, which is associated with the female gender.
Individuals with one large and one much smaller sex chromosome are XY, which is associated with the male gender.
Karyotype — an organized picture of the chromosomes in the nucleus
Parent Tip: Review the logic above to help your child master the concept of heredity worksheet for middle school.
