U6T8 – Muscle Contraction

The image above shows a muscle fibre. Name organelle A

The image above shows a muscle fibre. Name organelle C

The image above shows a muscle fibre. Name organelle E

The image above shows a muscle fibre. What is the function of organelle E?

In the above image, which type of protein makes up the myofilaments labelled C? type your answer in carefully.

In the above image, name the unit represented by B.

The muscle filament in the above diagram is relaxed, what would happen to the following zones when it contracts?

Which of the above diagrams represents either end of an 'A Band' in muscle?

Which of the above diagrams represents the myofilaments an 'M line' in muscle?

Which of the above diagrams represents the myofilaments a 'Z line' in muscle?

Which protein found in a myofilament has multiple globular heads? (Type your answer carefully).

Which protein blocks the actin-myosin binding site in a relaxed myofibril?

In the sliding filament theory, what causes the actin-myosin binding site to be exposed?

Name the molecule that carries out the function : Attaches to the Z line at the end of the sarcomere.

Breaks down ATP on myosin head

One role of ATP in muscle contraction is to provide the energy required for the 'powerstroke' of the myosin head. What is the other use of ATP in muscle contraction?

One form of muscle disease is caused by a mutated allele of a gene. This leads to production of myosin molecules that are unable to bind to other myosin molecules. If myosin molecules are unable to bind to other myosin molecules, this prevents muscle contraction. Suggest why.

What is the role of phosphocreatine in muscle contraction?

Which of the following are features of slow twitch muscle fibres:

A)Lots of aerobic respiration
B)Lots of mitochondria
C)Low levels of myoglobin

Which of the following is a feature of fast twitch muscle fibres when compared to slow twitch.