1. Biology EOC Review:
Unit 4
Heredity & Genetics

2. Key Concepts: DNA Structure
Things to Remember:
DNA is a nucleic acid made of two sugar backbones and 4 different nucleotides.
The four nitrogenous bases are:
Adenine
Thymine
Cytosine
Guanine
A goes with T
C goes with G

3. Key Concepts: DNA Replication
Things to Remember:
DNA Replication uses a strand of DNA to create an identical copy.
To do this, DNA unzips and one half is copied by an enzyme to create two identical strands.

4. Key Concepts: DNA Transcription & Translation
Things to Remember:
DNA Transcription and Translation make proteins.
The end product of DNA transcription is the creation of an RNA strand.
The end product of DNA translation is the creation of amino acids.
Animo acids strings together to form proteins.

5. Key Concepts: Genetics
Things to Remember:
DNA contains our genetic code.
Dominant genes are represented by capital letters
Recessive genes are represented by lowercase letters.
Dominant genes mask recessive traits.

6. Key Concepts: Genetics
Things to Remember:
Homozygous dominant – DD
Homozygous recessive – dd
Heterozygous – Dd
Punnett Squares can be used to help determine the percent chance of offspring having certain traits.

7. Key Concepts: Genetics
Things to Remember:
There are some special exceptions, such as:
Pattern of Inheritance
Definition
Example
Incomplete Dominance
Heterozygous phenotype that is a BLEND of the two homozygous phenotypes
When a red flower crosses with a white flower, pink flowers are produced
Codominance
Heterozygous genotype that EQUALLY EXPRESSES the traits from both alleles
When a red flower crosses with a white flower, red and white spotted flowers are produced.
Polygenic Traits
Trait that is produced by TWO OR MORE genes
Eye color, skin color, and hair color
Epistatic gene
A gene that can prevent the expression of all other genes.
Albanism – the lack of pigment in skin, hair, and eyes.

8. More Review Visual and Auditory Learner (Learn by Watching/Listening):
YouTube: How to Draw a Punnett Square
YouTube: Amoeba Sisters Punnett Squares
YouTube: Amoeba Sisters Dihybrid Crosses
YouTube: Amoeba Sisters Patterns of Inheritance
Kinesthetic Learners (Learn by Doing):
- Online Punnett Square Practice