<span>C. controls which substances enter and exit the cell
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I think 1 is C and 2 is A
Answer:
pic 1 red giant, a star whose outer shell has expanded and cooled
pic 2: supernova, a shock wave produced by extremely high temperatures
pic 3: black hole, a high mass star that has collapsed from gravity
pic 4: white dwarf, a low mass star that has shed its outer layers
Explanation:
Answer:
47
Explanation:
We all know that gametes like egg cell and sperm have haploid set of chromosomes but here as per this question she has produced 2 copies of chromosome 21. For the sake of maintaining haploidy, she was supposed to have only a single copy of chromosome 21 as a result of which her egg cell was supposed to have 23 chromosomes not 24.
But, this is a case of non dis-junction. Also, in a normal sperm there are no such copies of any chromosome i.e. there is a haploid set of chromosomes. It means that sperm must be having only 23 chromosomes. So we can easily infer that when the egg cell and sperm will fuse, the zygote will have 47 chromosomes (24 from egg cell and 23 from sperm).
Answer:
DNA replication
Explanation:
DNA is the genetic material and serves to store genetic information. The genetic information is transmitted from a parent cell to the daughter cells or from the parent to the progeny by the process of DNA replication.
DNA replication is the process that occurs in the nucleus in eukaryotes and includes the synthesis of new DNA strands using the existing DNA strands as a template. The newly formed DNA molecules are then distributed among the daughter cells during cell division. Thereby, the process of DNA replication ensures that the DNA of the parent generation is carried to the next generation.
For instance, sperms and egg cells in humans carry the DNA of male and female parents respectively to the young one. DNA replication occurs in sperm mother cells and egg mother cells during the formation of sperms and egg cells respectively.