Answer:
Courtney is looking at Prokaryotic Cell.
Explanation:
Ok, when Courtney is observing the science experiment, and finds a cell that includes DNA and has a nucleoid region but does not have nucleus, it is a prokaryotic cell and only the single-celled organisms of the domains Bacteria and Archaea are classified as prokaryotes, where pro means before and kary means nucleus.
Let's explain what is a prokaryotic cell: prokaryotes are unicellular organisms that lack organelles or other internal membrane-bound structures. Therefore, they do not have a nucleus, but, instead, generally have a single chromosome: a piece of circular, double-stranded DNA located in an area of the cell called the nucleoid. And most prokaryotes have a cell wall outside the plasma membrane.
Both human and bacteria cells contain DNA and both have a outer membrane that controls how materials come into and leave the cell.
Predominantly multicellular not in bacteria but in human body
*Cell contains a nucleus and other membrane bound organelles not in bacteria but in human body..
*DNA occurs in a circular form* in bacteria only..
* Ribosomes size in bacteria 70s and in human body 80s
*Capable of growth at temperatures greater than 80 C only in bacteria
*His tone proteins present in cell only in human body cells
* Operons present in DNA only in bacteria..
The independent variable is the amount of water consumed by the football players.
The dependent variable is the football players' endurance, measured by how many times they can run up and down the bleachers before catching their breaths.
The coach's hypothesis was that the more water consumed, the more endurance the players will have.
There is not a control group present in this experiment, but it would be the set of players who did not drink a bottle of water before practice.
The experimental group is the set of players who did drink a bottle of water before practice.
The constants in the experiment are the operational definitions of endurance (how he measures their endurance), the amount of water each player drinks throughout the week, and the players used in the experiment.
The lack of a set control group poses a threat to the accuracy of the experiment's results.
Answer:
The right answer is Letter A
Explanation:
The proposed model for the mechanism of initial transcription that suggests the entire RNA polymerase enzyme moves along the DNA is <em>transient-excursion model</em>, and the proposed model that is best supported by experimental findings is<em> scrunching model.</em>
<em>Because RNA polymerase leaves the promoter, translocate a short way along DNA template, synthesizes a short transcript before aborting transcript, releasing the transcript and returning to its original location on promoter. That is the transient-excursion model.</em>
<em>The scrunching model downstream DNA is pulled into the enzyme and has accumulated within the enzyme as single stranded bulges.</em>
<em>Experiments show that scrunching is right, experiments using single molecule analyses that allow the positions of different parts of polymerase to be measured relative to each other and to the template DNA during transcription.</em>
