Any two effects of gravitational force are as follows:
1. The Earth's gravitational force accelerates objects when they fall.
2. It constantly pulls, and the objects constantly speed up.
<h2>Answer </h2>
Lactic acid fermentation ocurrs in muscle cells when oxygen is in low supply
<u>Explanation</u>
The lactic acid fermentation in the muscles cell occurs when muscles work faster and it occurs due to the lack of supply of oxygen in the cell. The lactic acid fermentation is a type of aerobic respiration. The lactic acid formation is due to excessive exercise by individuals and oxygen which is essential for living, is less in the muscle which causes the feeling of burning in the muscles.
Crossing over occurs at the four-strand stage when two homologous chromosomes, each consisting of a pair of sister chromatids, are paired. Each crossover involves just two of the four strands and generates two recombinant strands.
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