This document provides an overview of DNA and genetics. It discusses that DNA forms chromosomes which occur in pairs in human cells. It defines DNA as a long molecule located in cell nuclei that is composed of a sugar backbone and bases. A gene is a sequence of bases that encode for proteins and traits. It also discusses that genetic traits are physical characteristics brought about by gene expression and are passed from parents to offspring via alleles. The document includes links to virtual DNA extraction and genetic trait games to reinforce these concepts.

1. Genetics 2- DNA
Jesse and Kara

2. Outcomes
What will you be learning and doing:
What is DNA? What is a Gene?
Item 1
DNA forms chromosomes and chromosomes
Item 2
occur in pairs within the human body
Virtual Lab DNA extraction
Item 3
In the lab: DNA extraction from strawberries
What are genetic traits and how are they
Item 4 passed on
The genetic traits game-True or False
Item 5

3. What is DNA? What is a Gene?
• DNA stands for Deoxyribonucleic acid
• It is a long, twisted molecule which is located
within the nucleus of any plant or animal cell
(with the exception of red blood cells)
• The long stranded molecule is composed of a sugar
backbone with branching arms called bases
• When un-twisted, DNA looks a bit like a ladder with the
sugar forming the two sides and bases forming the rungs
• A gene is composed of a sequence of bases which
encode for many different proteins and traits

4. DNA is packaged into chromosomes
• In order for DNA to fit into the nucleus
of the cell, it must be packaged into
structures known as chromosomes
• If DNA of the cell wasn’t packaged in this way,
the DNA strands would extend up to 5 or 6 feet
• Every human cell contains 46 chromosomes of DNA:
these chromosomes consist of of 22 pairs of
autosomal chromosomes (which are numbered 1-22)
and a pair of sex chromosomes with:
• Females having an XX pair
• Males have an XY chromosome pair
http://learn.genetics.utah.edu/content/be
gin/traits/karyotype/

5. Virtual DNA Extraction
http://www.learn.genetics.utah.edu/con
tent/lab/extraction

6. DNA Extraction from Strawberries
http://www.murdoch.edu.au/Biotech-out-
of-the-box/_document/Kit-Handout-
Sheets/DNA-extraction-from-
strawberries.pdf

7. What are Genetic Traits?
• Genetic traits are physical characteristics
brought about by the expression of a gene
or many genes, examples include things like
eye colour and hair colour. Variations in
these traits are dependant on the alleles
passed from a offsprings parents.
• Alleles are alternative forms of a gene which arise from
mutations and are found at the same place on a
chromososme

8. Is it a trait?
Is the following a trait – true or false?
EXAMPLE OF TRAIT ANSWER
• Eye colour • True
• Hair colour • True
• Tongue rolling • True
• Cancer • False- while there is a genetic
risk, also have to have
environmental component
• Windows Peak • True
• Handedness (left vs right)
• False- you can learn to an
extent
• Down Syndrome
• False- caused by extra
chromosome
• Detached earlobes • True
• Hitch-hikers thumb
• True

9. Thanks You
Any Questions?