Week 5 - Sliding filaments theory

Question 1

Sliding filament model/theory

Answer 1

Interaction of myofilaments cause muscle contraction and shortening

Question 2

Myosin

Answer 2

Thick filaments are bundles of myosin molecules

Question 3

What does each globular head of myosin have

Answer 3

Myosin ATPase site and an Actin binding site

Question 4

Actin

Answer 4

Thin filaments are paried chains of actin molecules each with a myosin binding site

Question 5

Brown strands that wrap around Actin

Answer 5

Tropomyosin

Question 6

Troponin

Answer 6

Holds tropomyosin in place

Question 7

What prevents myosin from binding to the myosin binding sites on actin

Answer 7

Tropomyosin covers the binding sites and troponin holds tropomyosin in place

Question 8

What is the key to unlock troponin

Answer 8

Calcium

Question 9

Where is calcium stores in the muscle

Answer 9

Sarcoplasmic reticulum

Question 10

Cross-bridge

Answer 10

Attachment of myosin to Actin

Question 11

What is the energy molecule in the body?

Answer 11

Adenosine Triphosphate (ATP)

Question 12

ATP turns into what when ATPase comes along

Answer 12

Adenosine Diphosphate (ADP) + Energy

Question 13

Stages of sliding filament theory

Answer 13

1. Exposure of Active sites
2. Cross-Bridge formation
3. Power stroke
4. Cross-Bridge release
5. ATP to ADP and P
6. Recovery stroke
   Cross bridge cycling will occur again if Calcium is still connected to troponin

Question 14

Without ATP what occurs and an example

Answer 14

Myosin and actin remain bound

In rigor mortis, the muscles stiffen because there is no ATP to release the bond

Question 15

Functions that require ATP within the muscle

Answer 15

Power stroke
Release of myosin from actin after power stroke
Transporting calcium back to sarcoplasmic reticulum