L16

Question 1

Motor proteins and movement invovle converting type of energy (ATP) into what type of energy

Answer 1

Converting chemical energy (ATP) to kinetic energy

Question 2

What moves along the actin filament

Answer 2

myosin

Question 3

Humans have ____ myosin genes

Answer 3

13

Question 4

What is myosin II involved in?

Answer 4

is involved in muscle contraction and cytokinesis

Question 5

The Stria of skeletal muscle comes from the _____

Answer 5

actomyosin complex

Question 6

Label myosin, actin, titan in slide 5

Answer 6

yellow: titan
blue - actin
orange - myosin

Question 7

Label myosin, actin, titan in slide 6

Answer 7

yellow: titan
blue - actin
red - myosin

Question 8

____ extending from the thick filament

Answer 8

myosin heads

Question 9

Describe the features of the myosin motor domain

Answer 9

1. Lever arm
   - long alpha helix w/2 light chains
2. Actin binding cleft
3. Attachment to thick filament
4. Converter
   - changes shape when phosphate is released
5. ADP molecule

Question 10

How many chains in myosin?

Answer 10

3 chains

Question 11

What molecule is bound to ADP in myosin

Answer 11

Mg2+

Question 12

What is the power stroke?

Answer 12

The release of the phosphate left over after ATP is cleaved that powers the stroke.

Question 13

Describe the pre-power stroke state and rigor-state

Answer 13

1. pre-power stroke state
   - the cleavage of ATP is used in the priming step
   - myosin adapts a bent, flexed form
2. rigor state
   - flexed myosin grabs the actin filament