Answer:
Cleavage is a process in which cell is divided into several parts without increasing in size. There are 4 stages of cleavage i. e. 2-cell, 4-cell, 8-cell and 16 cell stages. 2 cell embryo cleavage occurs after 30 hours of fertilization. 4 cell embryo cleavage occurs after 48 hours. 6 cell embryo cleavage occurs on third day of fertilization. 8 cell embryo cleavage occurs on fourth day of fertilization and more than 100 cells are formed.
Answer:
Fossils of mollusks would be found in lower strata than that of arthropods
Explanation:
Fossils are found in different layers of sedimentary rocks. The fossils of organisms that evolved earlier are found in the lower strata while those evolved later are preserved as fossils in the upper strata. If mollusks evolved before arthropods, fossils of arthropods would be present in upper layers while those of mollusks would be found in deeper layers.
I found this in a website, “A mutation is a change in DNA, the hereditary material of life. ... So a change in an organism's DNA can cause changes in all aspects of its life. Mutations are essential to evolution; they are the raw material of genetic variation. Without mutation, evolution could not occur.”
Branliest please?
The warm air will rise because cold air is heavier than warm air.