DURING MUSCLE CONTRACTION ...1] SIZE OF A BANDS REMAIN THE SAME 2] SIZE OF H ZONE BECOMES SMALLER 3] SIZE OF I BAND DECREASES 4] DIAMETER OF FIBRE INCREASES
During muscle contraction,
- Length of A band remains constant.
- I bands shorten
- H zone narrows
- Volume of contacted muscle remains same.
Note: All the given options are right and since there is no 'all the above' option, I could not interpret your query. Please be little specific so that I could provide you meaningful help.