Answer:
the correct answers are as follows
12:
b. Testcross- an organism with dominant phenotype but unknown genotype is crossed with homozygous recessive organism for the same trait. Based on the results obtained, if all offsprings have the same phenotype, then the parent is homozygous, but when a 1:1 ratio is observed in the offsprings, then the parent is heterozygous.
13.
e. Watson and Crick- they both used the crystallographic images from Franklin, analyzed them to first elucidate the 3D structure of the DNA and propose it to the world.
14.
c. Intracellular and commonly found in the cytoplasm- the receptors of steroid hormones are generally present within the target cell either in the cytoplasm or nucleus, since they alter gene expression.
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e. Certain prokaryotes/bacteria- this is a process that will enable disease-causing pathogens to communicate and cooperate with their group, by the release of autoinducers that increase their cell density.
Answer:
The need for DNA replication
DNA replication is the process by which a cell makes an identical copy of its DNA. This process is performed at the beginning of every cell division so that when the cell divides, each daughter cell will inherit an identical copy of the DNA.
Requirements for DNA replication
Original DNA template - DNA is a double helix made of two complementary strands. Each strand can be used as a template to create a new DNA molecule.
Free DNA nucleotides – needed to form the new strands.
DNA polymerase – an enzyme that adds new nucleotides to a growing strand of DNA.
Primers – A primer is a short strand of nucleotides that will bind to the 3’ end of the template DNA strand allowing DNA polymerase to add free DNA nucleotides.
Explanation:
https://www.bbc.co.uk/bitesize/guides/zrwhrj6/revision/1
Its false because lobsters have swimmerets as well and they dont use them only for swimming