Muscles

Question 1

What do sarcomeres make up?

Answer 1

The myofibrils in the muscle fibres s

Question 2

What is the Z line?

Answer 2

The end of the sarcomeres

Question 3

What is the A band?

Answer 3

Myosin present (actin and myosin or myosin only)

Question 4

What is the I band?

Answer 4

Actin only- stains less heavily (lighter under a microscope as it is less dense)

Question 5

What is the H zone?

Answer 5

Myosin only

Question 6

Which one is thicker out of myosin and actin?

Answer 6

Myosin is thicker
Actin is thinner

Question 7

The importance of ATP for muscle contraction?

Answer 7

ATP binds to the myosin heads to break the actin-myosin cross bridges
ATP is hydrolysed to reset/bend the myosin head so the myosin head can reattach to the actin
ATP is needed to actively transport the Ca 2+ ions back into the sarcoplasmic reticulum

Question 8

Creatine phosphate?

Answer 8

Is a source of phosphates
For the synthesis of ATP

Question 9

Antagonistic pairs?

Answer 9

Muscles work in pairs
One muscle pulls in one direction at a joint and the other pulls in the opposite direction
Example: biceps and triceps, quads and hamstrings

Question 10

What happens to a muscle when it relaxes?

Answer 10

Cross-bridge cycle stops
Contraction of antagonistic muscle will cause extension of sarcomere

Question 11

What is a tendon and what is its function?

Answer 11

Lengths of connective tissue that join skeletal muscle to bone

Question 12

Definition of actin?

Answer 12

Thin fibre made of 2 filaments that twist around eachother

Question 13

Definition of myosin?

Answer 13

Thicker fibre and consists of long tails with rounded projections/heads