Summary
In this section, we discussed the basic concepts of genetics, what genes are, and how they are passed on in families.
The main points addressed were as follows:
- All of our organs and tissues are made up of cells; in the middle of our cells is the nucleus, which contains our chromosomes.
- Chromosomes are tiny stick-like structures that contain all of our genes.
- We each have 23 pairs of chromosomes. Half of them come from the mother and the other half of the chromosomes come from the father.
- Chromosomes are numbered from largest to smallest.
- Men and women share chromosome pairs 1-22 in common.
- Pair 23 contains the sex chromosomes. Women have XX and men have XY.
- Genes are the instructions for how we grow and develop.
- DNA is the chemical that makes up genes and tells them what to do.
- DNA is is made of smaller units called nucleotides.
- There are four types of nucleotides, known by letters A, C, T, and G.
- A always pairs with T, while C always pairs with G.
- These pairs join together like steps in a ladder to provide the instructions for how we grow and develop.
- These chemical ladders twist tightly to form a helix, which twists even more to form a chromosome.
- A mutation occurs when a piece of the chemical ladder is either missing or added.
- Most mutations are not harmful, but some mutations may cause your genes not to do their job properly in your body.
- Some harmful mutations can lead to cancer.