Answer:
True
Explanation:
Chiasma is the site of crossing over. It is an X-shaped site that appears in a tetrad (bivalent) chromosome during the diplotene stage of prophase I of meiosis I. Crossing over refers to the exchange of segments of chromatids and occurs between homologous chromosomes only. Crossing over is the event of prophase I of meiosis I and produce new gene combinations.
The homologous chromosomes are separated from each other but remain attached at chiasmata. The dissolution of chiasmata occurs by the end of prophase I and separates the homologous chromosomes completely from each other. Crossing over does not occur in mitosis. Since mitosis does not include crossing over, chiasmata are also not formed in mitosis.
Do you mean ion pumps in the membrane of cell?
If so, then ion pumps maintain an electrochemical gradient across the membrane.
I believe it is number 3.
Hope this helps!
Explanation:
Food gives us energy and builds our body. If we do not eat regularly, we will become weak.
