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.
<span>Cocaine is an indirect agonist of dopamine <span>receptors which</span> means he </span>has no specific agonist activity at the dopamine receptor<span> but he enhances his activity. Cocaine</span> acts by binding to the dopamine transporter, blocking the removal of dopamine from the synapse and blocking termination of dopamine signalling. As a result, it increases the extracellular concentration of dopamine and therefore signal to the receiving neurons is amplified.
Answer:
Uranus
Uranus' axis is tilted, so it rotates from top to bottom.
Answer:
The average density of deer in 1923 was 1 deer per 8 acres
Explanation:
Given -
In 1923, the population of deer rose to 
The density of any species is equal to total population divided by total area of the land in which this population is residing.

Where d represents the density
P represents the population and
A represents the area of land
Substituting the given values in above equation, we get -

Thus, the average density of deer in 1923 was 1 deer per 8 acres
Answer: The estimated population is 1250 mice
Explanation: The method use was marked and recapture, in which individuals are marked in the first capture and after some time biologist trap a new group of individuals that can be or not marked
Whit this data is possible to estimate the size of a population applying the Peterson method but is important to make some considerations such as:
1. All indivuals have the same probability to be capture
2, The population remain constant in terms of birth and death rate.
Taking this into account, the formula that allows to determine the size of the population is:
N=CM / R
where N is the size of the population, C is number of indivuals trapped in recapture, M is number of individuals marked in the first capture and R is the number of marked animals trapped in recapture
In this case:
N = 250 * 200 / 40 = 1250