Why is it important to eat a protein-rich diet?

controversy- (kan ‘tra ver se)- (noun)- an argument that involves many people who strongly disagree about something; a dispute

There is a great deal of controversy surrounding the manager’s decision to trade the team’s star pitcher.

Look around the room….

• Find 3 physical differences between yourself and the people near you

• 1.• 2.• 3.

What macromolecule is responsible for these differences?

PROTEINSkin and eye color pigment are due to the protein

melanin• Nose shape is due to the protein cartilage; strength

due to protein of muscle• Lactase enzyme is a protein.• Growth hormone is a protein.

• You are unique because of the proteins present in your body!

What are proteins made of?

• Long chains of…..

AMINO ACIDS

Where do these amino acids come from?

• The protein-rich food you eat!– Cheese

– Egg white

alanine

trypt valine

isoleucine

There are 20 different amino acids found in your food.

• Milk is a ‘complete protein’ - it has all the essential amino acids.

• Rice and beans together make a ‘complete protein’.

*You need a complete set of all 20 Amino Acids in your body so your cells can make the required proteins!

*The code of nucleotides in DNA tells the cell how to make proteins

*Amino Acids are made of 3 Nitrogen Bases (triplet)

A T T C G G C T T A G C A A C

= Amino Acid

Central Dogma of BIOLOGY!

Central Dogma=Protein Synthesis• 2 major parts of Protein

Synthesis:1. Transcription: copying the DNA code into mRNA, takes place in nucleus

2. Translation: reading the mRNA code and assembling the protein from the waiting amino acids, takes place in cytoplasm

Who are the players in protein synthesis?

Gene – Section of DNA that codes for a specific protein. There are LOTS of genes in your DNA

Messenger RNA (mRNA) – The complementary copy of nitrogen bases copied from template strand of DNA

RNA: the “middle man” in protein synthesis

• 3 differences between RNA and DNA:1.) RNA is a single stranded molecule2.) RNA has a ribose sugar 3.) Contains the nitrogenous base uracil instead of thymine

Used to make mRNA, tRNA, and rRNA

Does this diagram represent DNA or RNA? How can you tell?

DNA RNA

- Double stranded molecule

- Contains Thymine

- Contains deoxyribose sugar

- Found only in nucleus

- Single stranded molecule

- Contains uracil

- Contains ribose sugar

- Found in nucleus and cytoplasm

- Made of nucleotides

- Contain adenine, guanine and cytosine

Both

Please draw this in your notes!

Transcription – copying the DNA into mRNA

• 2 DNA strands split exposing active strand

• mRNA nucleotides pair with the complementary DNA nucleotides

TranscriptionYou can use the same base pair rules that we used for DNA, except that instead of Thymine (T) we have Uracil (U) that binds to A

•A-U•G-C•T-A•C-G

How is the RNA made?

• RNA is made from DNA by an enzyme called RNA polymerase

What would the mRNA sequence be?

DNA:

5’-ATCGTTG-3’3’-TAGCAAC-5’

When look at the DNA strand you always use the side that is labeled 3’-5’

What would the mRNA sequence be?

DNA:

5’-ATCGTTG-3’3’-TAGCAAC-5’

mRNA:

5’-AUCGUUG-3’

What would the mRNA sequence be?

DNA:

5’-CCGTATA-3’3’-GGCATAT-5’

What would the mRNA sequence be?

DNA:

5’-CCGTATA-3’3’-GGCATAT-5’

mRNA: 5’ -CCGUAUA -3’

Transcription Exit Ticket

• Since RNA is made from DNA how would you expect the RNA to change in the DNA contains a mutation?