1060- Muscles

Question 1

skeletal muscle structure

Answer 1

large cells, appear multinucleated , striped structure

Question 2

smooth muscle structure

Answer 2

appears layered with lots of nucleus’ , each cell is surrounded by a basal lamina with a small amount of connective tissue between the cells. (which allows a passage of nerve tracts and blood vessels ).

Question 3

3 similarities between skeletal and cardiac muscle cells

Answer 3

both are striped, have sarcomere structures and contain organised tubular myofibrils

Question 4

4 differences between skeletal and cardiac muscle cells

Answer 4

cardiac muscles are ; shorter, branched and multinucleate. T-tubules are also longer.

Question 5

The function of t-tubules in striated muscle

Answer 5

to maintain the sarcoplasmic reticulum ca2+ store under the tight control of membrane depolarisation .

Question 6

What initiates the contraction in smooth , skeletal and cardiac muscle cells?

Answer 6

no troponin so ca2+ initiates contraction , ca2+ combined with troponin initiates contraction , ca2+ initiates contraction for cardiac muscles.

Question 7

For which muscle types are action potentials required ?

Answer 7

Only skeletal muscles.