B.
Key word: slide
Think of sliding down a WATER slide.
Answer:
d-stem
Explanation:
Cellulose is most abundant in meristems tissues which are present in the tips of the root and stem and in the cambium between the xylem and the phloem and under the epidermis of the trees and shrubs, therefore it is abundant in the stems.
Meristems are also found in other parts of the plant but it is mostly abundant in the stems.
Meristems are the cells that are responsible for the cell growth and elongation.
Answer:
Option c. Only the haploid organism may also reproduce asexually.
Explanation:
It is scientifically approved that algae and fungi are able to form true asexual spores. This process of spore formation involves mitosis and resultant spore is called mito-spore which develop into new offspring.
Reference: Smith, B. A., and DANIEL D. Burke. "Evidence for the presence of messenger ribonucleic acid in Allomyces macrogynus mitospores." Journal of bacteriology 138.2 (1979): 535-541.
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).
Hello. This question is incomplete. The full question is:
"You determine that you have only 3 copies left of an important DNA fragment, so you decide to amplify it. Using flanking primers, how many PCR cycles would you have to run to generate over one billion (10^9) copies of the fragment?
"
Answer:
Approximately 29 cycles of PCR would be required.
Explanation:
As you may already know, PCR is a technique used in molecular biology that allows part of a DNA molecule to be recycled into millions of copies.
PCR allows this replication to be done through cycles. Each PCR cycle lasts about 2 minutes and allows the DNA molecule to undergo the separation of the strands, the binding of the primers and the synthesis of new DNA strands through DNA polymerase. This cycle is usually repeated 32 times, but this number may change depending on the number of copies the researcher thinks is necessary.
In this case, if a researcher wants 10 ^ 9 copies of DNA, he must do the following calculation to find the number of PCR cycles needed:
32 ^ x = 10 ^ 9
x = 28.3 = approximately 29 cycles.
