Tuesday, March 6, 2012Open to entry- Protein Networks from yesterday

Homework:1) Cell Transport retakes in tutorial- LAST DAY2) Quiz on Protein Pathways/Protein Structure- FRI3) Serotonin Pathway worksheet- due on Block Day

“Coat Color in Labrador Retrievers”

Cocoa Midnight

Guiding Question:

“How does variation exist between organisms?”

Read: “Coat Colors in Labrador Retrievers” to help you answer this question.

Vocab to know for reading.• Pigment = A substance, such as chlorophyll or

melanin, that produces a characteristic color in plant or animal tissue.

• Skin and Hair pigments are produced in cells called melanocytes.

• Synthesize = to put together.

Labrador (dog) pigmentation

Tyrosine Dopaquinone

Brown pigment

Black pigment

Yellow pigmenttyrosinase

TRP-2

TRP-1Boxes = metabolitesArrows = enzymes that change the metabolites

What will be the dog’s coat color?

BLACK

Tyrosine Dopaquinone

Brown pigment

Black pigment

Yellow pigmenttyrosinase

TRP-2

TRP-1

What would happen if the enzyme TRP – 1 was missing?

Black pigment

What color is the dog’s coat? Brown

Boxes = metabolitesArrows = enzymes that change the metabolites

Tyrosine Dopaquinone

Brown pigment

Black pigment

Yellow pigmenttyrosinase

TRP-2

TRP-1

So what would happen if the enzymes TRP – 1 and TRP-2 were both missing?

Black pigment

What color is the dog’s coat? Yellow

Brown pigment

Boxes = metabolitesArrows = enzymes that change the metabolites

Entry 17-Protein Pathways Practice- 3/6/12Make an entry:

Entry 17: Protein Pathways Practice- 3/6/12See attached

Pigment Metabolic Network for the Imaginary Bioflower

Blue Flower Purple Flower

Where is the variation in these flowers? Blue and Purple Flowers (Color)

BioflowersA colorless starting molecule is converted by

enzyme X to blue pigment. Next, enzyme Y converts the blue pigment to purple pigment.

1a.Diagram of the pathway. (include a key)

Colorless Compound Blue Pigment Purple PigmentX Y

1b.Give an explanation for a blue flower.Enzyme Y not available or not working

“Roundbuds”

Roundbuds

In another type of wildflower, the roundbud, red pigment is synthesized from a white precursor by enzyme Q.

1. Draw the enzyme pathway for the roundbud.

It was believed that all roundbuds were red until a knowledgeable, observant teenager discovered a meadow full of white-flowered roundbuds.

2. Using your knowledge of the synthesis pathway for red pigment, give an explanation for the white roundbud variety.

White Precursor Red PigmentQ

2a. Draw Enzyme Pathway

In another type of wildflower, the roundbud, red pigment is synthesized from a white precursor by enzyme Q.

2b. It was believed that all roundbuds were red until a knowledgeable, observant teenager discovered a meadow full of white-flowered roundbuds.

Enzyme Q is not working- therefore no conversion to red pigment.

2b. Using your knowledge of the synthesis pathway for red pigment, give an explanation for the white roundbud variety.

White Precusor Red Pigment

Q

YELLOW PIGMENT IS CONVERTED BY ENZYME Z INTO BROWN PIGMENT

• YELLOW CAN ALSO BE CONVERTED BY ENZYME W INTO RED PIGMENT

• BROWN PIGMENT IS CONVERTED BY ENZYME X INTO BLACK PIGMENT

• BROWN CAN ALSO BE CONVERTED BY ENZYME Y INTO ORANGE

YELLOW PIGMENT

RED PIGMENT

BLACK PIGMENT

BROWN PIGMENT

ORANGE

PIGMENT

Z W

XY

Chupacabra Coat Color

• Yellow= no Z or W• Brown= no X or Y, W• RED= no Z

#3. Fancy flowersa.

b. Red with white spotsc. No spots, red only

REDRED-WHITE SPOTS

RED-BLUE SPOTS

S T

A B C

D E F

12

34

5

#4 a. 1,2b. A,B, C, Dc. All except

Fd. 1, 3

Make an entry- Entry 18: Human Metabolic Networks- 3/6/12

Substrate Enzyme Product

Add to last question on back:How is a MAO inhibitor used to treat depression?