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Flashcards in Muscles Deck (25):
0

Which type of muscle is non - striated and not under conscious control?

Smooth muscle

1

Where would you find smooth muscle?

Sheets in the walls of hollow organs and tubular substances to regulate diameter and propel substances forward through tracts

2

Which nervous system controls smooth muscle?

Autonomic nervous system

3

Which muscle is voluntary, under conscious control, part of the so,attic nervous system, striped and striated?

Skeletal muscle

4

What are the property of muscle cells in skeletal muscle?

Several nuclei, many mitochondria, presence of myoglobin

5

What causes the skeletal muscle to contract and what happens when it does?

Stimulation from a nerves fibre - action potential spreads - conducted deep into the muscle cell rough a special network of channels that run through the sarcoplasm. Calcium released from intracellular stores. Calcium causes binding of myosin to actin filament forming cross - bridges, ATP provides energy for 2 filaments to slide over each other. Pulling z limes closer and shortening the sarcomere, if enough fibres are stimulated at the same time the whole muscle will shorten and contract.

6

What is the neuro transmitter involved in muscle contraction?

Acetylcholine

7

What constitutes a motor unit?

One nerve fibre and the muscle fibres it supplies

8

What does the strength of a contraction depend on?

Number of motor units in action at a particular time.

9

What type of motor unit would be used for larges Cale powerful movement?

One nerve serving many muscle cells

10

What kind of motor unit would be used for fine delicate movement?

One motor unit containing very few muscle fibres

11

What is the name of the connective tissue sheath covering the entire muscle?

Epimysium

12

What is the name of the connective tissue sheath covering the fascicles?

Perimysium

13

What is the name of the fine connective tissue layer covering the individual nerve cells?

Endomysium

14

What do tendons do?

Secure muscles to bone

15

What is the fleshy part of the muscle called?

The belly

16

What do ligaments do?

Bind bones together

17

What is the origin?

Point of attachment of a muscle to a bone that moves least during muscle contraction

18

Insertion

Where the muscle joins the bone

19

Agonist

Promotes movement

20

Antagonist

Resists movement, opposes a muscle

21

Flexors

Flex a muscle

22

Extensors

Extend a muscle

23

Describe the tendon jerk reflex

Stimulate patella tendon - body of lower motor neurone stimulated - sends a reflex along sensory neurone - bypasses brain - goes to spinal cord - stimulates motor neurone causing thigh muscle to contract and knee kick forwards. Protective response

24

Describe the pathway of a motor neurone?

Internal capsule - central peduncle - upper motor neurone - medullary pyramid - lateral corticospinaltract - ventral corticospinal tract - lower motor neurone - skeletal muscle