1. DNA: Gene Regulation and expression
Day 2
DNA: Gene Regulation and expression
Drill:
Label the three parts of DNA on the image:
Sugar / Phosphate / Base
Conceptual Q of the Day:
If all the cells in our body have the same genetic info, then why do we (and other organisms) look different?

2. Remember… What dna looks like?
DNA is made up of 3 key parts (NUCLEOTIDE):
Nitrogenous Bases!
Adenine – Thymine – Guanine – Cytosine
At The Grand Canyon
Phosphate Group
PO4
5 Carbon (C) Sugar
Ribose

3. Remember… Why is dna important?
DNA is important because it … genetic info :
STORES (is found in the nucleus)
REPLICATES (copies itself)
PASSES ALONG (your traits)

4. What are chromosomes? Chromosomes are tightly coiled DNA
You chromosomes are found in the nucleus of every cell
DNA for Euk it is in the nucleus
DNA for Prok it is in the cytoplasm
You have 23 pairs of chromosomes!
46 total: 23 from your mom and 23 from your dad

5. Do all orgs have 23 pairs of chromosomes?
Humans have 23 pairs of chromosomes
That’s 46 total!!
Chromosome pairs 1-22 are autosomes or non- sex chromosomes
Chromosomes X and Y are sex chromosomes
If you have 2 X’s (XX) you’re a female
If you have 1 X and 1 Y (XY) you’re a male
Different orgs are have different chromosome #s
Cats: 19 pairs of chromosomes
Mice: 20 pairs of chromosomes
Bananas: 16 pairs of chromosomes and one extra

6. What are Genes? Genes are segments of DNA on a chromosome
Each gene codes for a specific protein
They are the band on the chromosome
** In a nut shell:
DNA in the nucleus has chromosomes
Chromosomes have segments of DNA called genes
Genes make (code for) specific proteins
Proteins control your traits

7. Brain Break: Chromosome Pairs
Take the chromosome given and find your pair in the room.
When you find your pair share:
Your name
Your favorite food
Your favorite thing to do that isn’t be in Miss G’s class
Return to your seats, tape your chromosome at the bottom of your notes on the front
Label it “chromosome” and put an arrow pointing to a gene

9. How are traits expressed?

10. How are different genes expressed?
Cells are differentiated!! – meaning they will only make certain proteins
Even though all your cells have the same DNA they only code for certain proteins!
This is why we all look different!!
So not only this but genes can be turned on AND off allowing proteins to only be created at certain times… like insulin!
Gene  Protein  Trait
THINK ABOUT IT: When a frog is born, it lives as a tadpole and has a tail. There is a gene telling it to have a tail. As the tadpole develops into a frog, the tail disappears. The gene is NO longer being expressed.
Can you think of any other examples??

11. Gene expression activity
FORMAT: Create a PowerPoint of at least 4 slides OR a poster to illustrate and explain the relationship between DNA, chromosomes, and genes in the expression of traits.
With 1 partner, look at the image of the mouse and the fly.
Compare their structures during development and as adult organisms.
Use the images to explain why their cell DNA is similar (highlighted genes) but their physical traits are not.
Include the words: DNA, chromosomes, genes, regulation, protein, expression, and traits.

12. Activity: Gene Expression
8 chromosomes
40 chromosomes
FORMAT: Create a PowerPoint of at least 4 slides OR a poster to illustrate and explain the relationship between DNA, chromosomes, and genes in the expression of traits.
You and your partner will choose any two animals, find out how many chromosomes they have and explain how this relates to their physical traits.
Include the words: DNA, chromosomes, genes, regulation, protein, expression, and traits.

13. Exit ticket
When you are done with your gene expression activity find your exit ticket sheet in the folder on the chair up front.
In the first block (on the front) write a vocabulary word from the word wall.
In the first block (on the back) write the definition or draw an image of that word.
Do this for the second box at the top!
Extra points for three students who share out their vocabulary flash card!!