Please add the statements to choose from, i would love to help :)
The correct answer is that the H zone becomes narrower.
The H-band refers to the region of the thick filaments, which is not overlaid by the actin (thin filaments). Within the H-zone is a thin M-line, which is formed of cross-connecting components of the cytoskeleton.
At the time of muscle contraction, the A-bands do not vary in their length, whereas the H-zone and the I-bands shorten. This makes the Z-lines come near to each other.
Answer:
This time is divided into three stages, called trimesters.
Explanation:
First trimester, spans from conception to 12 weeks
Second trimester, spans from weeks 13 and 28.
Third trimester, spans from weeks 29 to 40.
https://my.clevelandclinic.org/health/articles/7247-fetal-development-stages-of-growth
G1- this phase stays around for 10/24 hours of the whole cells cycle.
