Lecture notes Microbiology 1

Chapter 8

Genetics




1

, Generic questions related to genetics and heredity




• “Who does she look like, mom or dad?”

• That’s probably one of the first few questions everyone asks
when hearing about a new arrival in the family.

• “Does she have Aunt Jane’s eyes? Uncle Joe’s nose?”

• These are some of the many noticeable characteristics that
can be passed down from family members.


2

, Genetics and heredity
DNA = Deoxyribonucleic acid
Genome = DNA
DNA = Genetic information
Base pairs = Nucleotides = Adenine, Thymine, Cytosine and Guanine
DNA is located in the nucleus of each cell


Each cell in our body (except the red blood cells) contains the entire human genome.
In the nucleus of every cell is the genetic information “blueprint” to construct an
individual (recipe for living things).
It is the sequencing (order and arrangement) of DNA base pairs (nucleotides) in
cells that makes us unique.
Portions of the DNA strand makes up a gene.
The genes contain the instruction to make up proteins.
Human cells have 23 pairs of chromosomes (total 46 chromosomes) per cell.
Each chromosome, has DNA with a million base pairs (Adenine, Thymine,
3
Cytosine and Guanine).