3.4.4 Skeletal Muscles as Effectors Flashcards Preview

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Flashcards in 3.4.4 Skeletal Muscles as Effectors Deck (67)
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1

Muscles act as _____ and are stimulated to contract by _____

Muscles act as effectors and are stimulated to contract by neurones

2

What is skeletal muscle made up of?

Muscle fibres (large bundles of long cells)

3

What is sarcolemma?

Cell membrane of muscle fibre cells

4

What are transverse (T) tubules?

Folds = bits of sarcolemma fold inwards across muscle fibres and stick into sarcoplasm

5

What do T tubules do?

Help to spread electrical impulses throughout sarcoplasm so they reach all parts of muscle fibre

6

What is the sarcoplasmic reticulum?

Network of internal membranes that runs through sarcoplasm

7

What does the sarcoplasmic reticulum do?

Stores and releases calcium ions needed for muscle contraction

8

Muscle fibres are _______

Muscle fibres are multinucleate

9

Name 2 things muscle fibres have lots of

  • Mitochondria
    • Provides ATP needed for muscle contraction
  • Myofibrils (cylindrical organelles)
    • Made up of proteins and are highly specialised for contraction

10

State what 1) is

11

State what 2) is

12

State what 3) is

13

State what 4) is

14

State what 5) is

15

What is skeletal muscle (aka striated, striped or voluntary muscle)?

Type of muscle you move 

16

How is skeletal muscle attached to bones?

By tendons

17

Muscle Contraction 

What do bones acts as when a pair of skeletal muscles contract and relax to move bones at a joint?

So act as levers, giving muscles something to pull against

18

Muscles that work together to move a bone are called ________ ____

antagonistic pairs

19

Muscles act in Antagonistic Pairs

State what muscle is agonist

Contracting muscle

20

Muscles act in Antagonistic Pairs

State what muscle is antagonist

Relaxing muscle

21

Describe what happens when your biceps contracts

  • Biceps contract (agonist), triceps relaxes (antagonist)
  • Pulls bone so your arm bends (flexes) at the elbow

22

Describe what happens when your biceps relaxes

  • Biceps relaxes (antagonist), triceps contracts (agonist)
  • Pulls bone so your arm straightens (extends) at the elbow

23

Myofibrils contain thick and thin ____ that ___ ___ ____ ____ to make muscles contract

Myofibrils contain thick and thin myofilaments that move past each other to make muscles contract

24

What are thick myofilaments made from?

Protein myosin

25

What are thin myofilaments made from?

Protein actin

26

State what 1) is 

27

State what 2) is 

28

State what 3) is 

29

State what 4) is 

30

State what 5) is 

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