muscles

Question 1

3 types of muscles?

Answer 1

skeletal, cardiac, smooth

Question 2

skeletal muscle is aka

Answer 2

striated/voluntary

although can sometimes work involuntarily eg diaphragm

Question 3

skeletal muscle functions?

Answer 3

Attaches bone via tendon
Part of some sphincters: oesophagus, anus
movement, posture, heating, breathing

Question 4

what are muscle cells called

Answer 4

muscle fibres

Question 5

describe structure of muscle fibres

Answer 5

sarcomere
-actin going into Z bands
-myosin which overlaps actin
sarcomeres arrange into myofibrils

Question 6

describe how striations appear on microscopy

Answer 6

dark a bands are overlapping myosin and actin

light i bands are just actin

Question 7

size of skeletal muscle cells?

Answer 7

small or large

Question 8

nuclei in skeletal muscle fibres?

Answer 8

many due to syncytium - cells divide and fuse forming many nuclei to form many proteins
peripheraly located

Question 9

names for cytoplasm, cell membrane and er or muscle fibres?

Answer 9

sarcoplasm, sarcolemma, sarcoplasmic reticulum?

Question 10

whats neuromuscular junction

Answer 10

junction bt motor neuron and muscle fibre

Question 11

whats transverse tubules?

Answer 11

tubules extending from pm to sarcoplasmic reticulum

Question 12

describe how muscle movment occurs

Answer 12

Acetylcholin released at neuromuscular junction and bind to receptors on sarcolemma
Action potentials spread to the transverse tubular system (yellow tubes)
Causes sarcoplasmic reticulum membranes to release calcium
Calcium floods the myofibrils and sarcomere causing contraction of actin/myosin filaments.

Question 13

how do muscle fbres form muscle tissue

Answer 13

multiple muscle fibres form fascicles

multiple fasciles form muscle tissue

Question 14

describe connective tissue surrounding muscles

Answer 14

Endomysium: connective tissue surrounding individual muscle fibers
s
Perimysium: loose connective tissue surrounding fascicles
Epimysium: connective tissue surrounding whole muscle

Question 15

wheres cardiac muscle found

Answer 15

heart only

Question 16

describe cell shape and size of cardiac muscle

Answer 16

small and branched

Question 17

nuclei of cardiac muscle?

Answer 17

1-2 which are centrally located

Question 18

describe mitochondria of cardiac muscle?

Answer 18

many due to high metabolic activity

Question 19

are there lots of capillaries in cardiac muscle cells

Answer 19

yes

Question 20

how are cardiac muscle cells joined?

Answer 20

via intercalated disks - adherens type, desmosome and gap junctions

Question 21

function of smooth muscle?

Answer 21

walls of hollow tubes and organs

Question 22

difference between smooth muscle and other cell types?

Answer 22

no striations

Question 23

shape of smooth muscle?

Answer 23

fusiform - leaf

Question 24

nuclei of smooth muscle?

Answer 24

centrally located; only one

Question 25

how are smooth muscle cells joined

Answer 25

gap junctions