11.2 Movement

Question 1

Name of bone-bone connection

Answer 1

Ligament

Question 2

Name of bone-muscle connection

Answer 2

Tendon

Question 3

2 examples of synovial joints. What are synovial joints?

Answer 3

Allow certain movements, but not others.
1) Hinge joint (between Humerus and Ulna)
2) Ball & Socket joint (between Hip and Femur)

Question 4

What are the muscles called that cause opposing movements? Give 1 human and 1 insect example

Answer 4

Antagonistic muscle pairs
triceps & biceps, grasshopper legs

Question 5

Name the 5 levels of the muscle.

Answer 5

Muscle - Muscle bundle - Muscle fibre - Myofibril - Sacromere

Question 6

3 special things about muscle fibres

Answer 6

1) Multinucleated
2) lots of Mitochondria
3) specialised endoplasmic reticulum that stores calcium ions (aka sacroplasmic reticulum).

Question 7

Outline muscle contraction.

Answer 7

1) A musclefibre contains many myofibrils, which are made of sacromeres. When a motorneuron sends an impulse, it releases neurotransmitters, which cause the release of Ca+ ions from the sacroplasmic reticuluum.
2) The Ca+ ions bind to Troponin, which then moves the Tropomyosin, exposing the binding sites.
3) With ATP that gets hydrolised to ADP, the Myosin heads gain energy and connect to the binding sites, forming cross-bridges.
4) The actins move to the centre of the sacromere, which is called “sliding of filaments” .This causes the muscle to contract.