Our Questions about DNA?• What does DNA look like?

• How is DNA made?

• How do we know DNA has the instructions to make proteins?

• How does DNA instruct the cell to make proteins?

• WHAT DETERMINES THE ORDER OF AMINO ACIDS IN A PROTEIN???

Do the cells in your eye and your tongue have the same functions?

Do the cells in your eye and your tongue have the same proteins?

Do the cells in your eye and your tongue have the same DNA?

Humans have 46 chromosomes- where are they?

• Do all cells have DNA?

• Do all cells have the same DNA?

When doing DNA identification (think CSI) does it matter which cells you use to get the sample?

Cheek cells?Red Blood cells?Hair follicle cells?

What changes occur to a salmon when it spawns?

Do the salmon’s proteins change when it spawns?

Does a salmon’s DNA change when it spawns?

Does the DNA in your body change as you go through puberty?

Does the DNA in your body change as you go through puberty?

Writing assignment

1. Do different cells in your body have different DNA?

2. What makes you think that?

3. Does the DNA in your cells change as you develop from a baby to an adult?

4. What makes you think that?

What have we learned?

• Proteins determine most characteristics of a cell and organism

• Information stored in DNA determines which proteins can be made by a cell

• The environment influences which proteins are made by a cell

Some things we will learn…

• Where is protein made in a cell?

• How does the information stored in DNA determine which proteins can be made in a cell?

• How is protein made in a cell?

• How does the environment influence which proteins are made in cell?

Where is protein made in a cell?

DNA does not leave the nucleus of eukaryotic cells... but proteins are made

outside of the nucleus by ribosomes

human cheekcell mitochondria

chloroplasts

nucleus

vacuole

Elodea leaf cell

(DNA here)(DNA here)

DNA does not leave the nucleus of eukaryotic cells... but proteins are made

outside of the nucleus by ribosomes

nucleus(DNA here)

(DNA here)

ribosomes

(proteins made here)

(proteins made here)

DNA and ribosomes are at different locations in a prokaryoic cell.

E. coli bacteria cell

DNA

(proteins made here)

ribosomes

1. Add ribosomes to the diagrams you have been keeping in your notebook

1. Plant cell- elodea leaf cell

2. Animal cell- human cheek cell

3. Prokaryote- E. coli bacterium

2. Ribosomes make protein but are not in the same location as DNA in a cell. Discuss ideas with your classmates about how the proteins could be made according to the DNA information.

Information flow from DNA to trait

DNA protein Observed trait

Stored in nucleus

Made by ribosomes outside of nucleus

messenger RNA

• mRNA transfers information from the DNA in the nucleus to the ribosomes.

• Ribosomes build proteins according to the mRNA information received.

Information flow from DNA to trait

DNAmessenger

RNA protein Observed trait

Stored in nucleus

Made by ribosomes outside of nucleus

DNA information mRNA information

Transcription is the process used to convert DNA information into mRNA information.

Note: DNA does not become RNA; the information in DNA is copied as RNA

DNAmessenger

RNA