The answer to the first question is a.
Answer:
If your just looking for a description here you go.
Explanation:
Most spiral galaxies contain a central bulge surrounded by a flat, rotating disk of stars. The bulge in the center is made up of older, dimmer stars, and is thought to contain a supermassive black hole. Approximately two-thirds of spiral galaxies also contain a bar structure through their center, as does the Milky Way.
Hope this helps.
Answer:
zygote, fertilization
(haploid) spores, meiosis
a pollen tube
Answer:
it causes the rapid increase in PH which may harmful for the for fishes and other aquatic lives.
Explanation:
There are a lot of materials which are used to neutralize the acidity of soil.some examples of such materials are slacked lime, quick lime, and liquid lime etc. Lime increases the PH and the concentration of calcium which helps in removal of phosphate from water. Raising PH also cause to remove the carbon dioxide from the water. But keep in mind that rapid increase in PH is harmful for the fishes.calcium oxide also causes the rapid increase in Ph therefore, it is not advisable to use in fishpond.
